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Archives of Insect Biochemistry and Physiology

Impact factor: 1.515 5-Year impact factor: 1.378 Print ISSN: 0739-4462 Online ISSN: 1520-6327 Publisher: Wiley Blackwell (John Wiley & Sons)

Subject: Psychology

Most recent papers:

  • Potential of RNA interference in the study and management of the whitefly, Bemisia tabaci.
    Sajjan Grover, Vikas Jindal, Geetika Banta, Clauvis Nji Tizi Taning, Guy Smagghe, Olivier Christiaens.
    Archives of Insect Biochemistry and Physiology. November 28, 2018
    --- - |2- Abstract Whiteflies cause considerable losses to crops, directly by feeding, and indirectly by transmission of viruses. The current control methods consist of a combination of different control tactics, mainly still relying on unsafe and non‐ecofriendly chemical control. RNA interference (RNAi) is a post‐transcriptional gene‐silencing strategy in which double‐stranded RNA (dsRNA), corresponding specifically to a target gene, is introduced in a target organism. Research on RNAi in the previous decade has shown its success as a potential insect control strategy, which can be highly species‐specific and environment friendly. In whiteflies, the success of dsRNA delivery through the oral route opened possibilities for its management through plant‐mediated RNAi. To date, several genes have been targeted in whiteflies through RNAi and these assays demonstrated its potential to manage whiteflies at lab level. However, further research and investments are needed to move toward an application at field level. In this review, for the first time, we collected the literature on genes targeted for silencing via RNAi in whiteflies and discuss the potential of RNAi in whitefly pest control. We also discuss likely delivery methods, including transgenic in planta delivery and symbiont‐mediated delivery, and its potential for studying and interfering with insecticide resistance mechanisms and virus transmission by whiteflies. - 'Archives of Insect Biochemistry and Physiology, EarlyView. '
    November 28, 2018   doi: 10.1002/arch.21522   open full text
  • Protein–protein interaction network analysis of insecticide resistance molecular mechanism in Drosophila melanogaster.
    GuiLu Zhang, WenJun Zhang.
    Archives of Insect Biochemistry and Physiology. November 26, 2018
    --- - |2- The protein‐protein interaction network of insecticide resistance molecular mechanism (a). Sub network of nodes with higher value (b). The degree centralityin (c) of insecticide resistance network in D. melanogaster. The color of every node is changed according to the different degree values or combined score. Prosalpha6, CG9674, RpL40, Akap200, Prosalpha6 are the highest value in DC, BC, CC, CU, EC respectively. They are diamond shaped. The number in or outside parentheses is the degree centrality or protein ID code. Abstract The problem of resistance has not been solved fundamentally at present, because the development speed of new insecticides can not keep pace with the development speed of resistance, and the lack of understanding of molecular mechanism of resistance. Here we collected seed genes and their interacting proteins involved in insecticide resistance molecular mechanism in Drosophila melanogaster by literature mining and the String database. We identified a total of 528 proteins and 13514 protein–protein interactions. The protein interaction network was constructed by String and Pajek, and we analyzed the topological properties, such as degree centrality and eigenvector centrality. Proteasome complexes and drug metabolism—cytochrome P450 were an enrichment by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. This is the first time to explore the insecticide resistance molecular mechanism of D. melanogaster by the methods and tools of network biology, it can provide the bioinformatic foundation for further understanding the mechanisms of insecticide resistance. - 'Archives of Insect Biochemistry and Physiology, EarlyView. '
    November 26, 2018   doi: 10.1002/arch.21523   open full text
  • Water channel activity of putative aquaporin‐6 present in Aedes aegypti.
    Sandhya Sreedharan, Kavitha Sankaranarayanan.
    Archives of Insect Biochemistry and Physiology. November 19, 2018
    --- - "\nAbstract\nAquaporins (AQPs) are integral membrane channels that facilitate the bidirectional transport of water and sometimes other small solutes across biological membranes. AQPs are important in mediating environmental adaptations in mosquitoes and are considered as a novel target for the development of effective insecticides against mosquitoes. Here, we expressed Aedes aegypti AQP6 (\nAaAQP6) in human embryonic kidney (HEK) 293 cells and analyzed the water permeability by a conventional swelling assay, that is, a real‐time change in cell size corresponding to the cell swelling induced by hyposmotic solution. The swelling assay revealed that \nAaAQP6 is a mercury‐sensitive water channel. Gene expression studies showed that \nAaAQP6 is highly expressed in the pupae than other developmental stages. Heterologous expression of \nAaAQP6 in HEK cell was mainly observed intracellularly suggesting \nAaAQP6 possibly could be a subcellular water channel and may play an osmoregulatory function in the pupae of \nA. aegypti.\n" - 'Archives of Insect Biochemistry and Physiology, EarlyView. '
    November 19, 2018   doi: 10.1002/arch.21519   open full text
  • Olfactory attraction mediated by the maxillary palps in the striped fruit fly, Bactrocera scutellata: Electrophysiological and behavioral study.
    Kye Chung Park, Seon Ah Jeong, Gimyon Kwon, Hyun‐Woo Oh.
    Archives of Insect Biochemistry and Physiology. November 16, 2018
    --- - "\nAbstract\nHere, we report that the olfactory attraction of the striped fruit fly, Bactrocera scutellata (Hendel; Diptera: Tephritidae), a serious pest of pumpkin and other cucurbitaceae plants, to cue lure and raspberry ketone is mediated by the maxillary palps. The antennae, bearing three morphological types (basiconic, trichoid, and coeloconic) of olfactory sensilla, in male and female \nB. scutellata exhibited significant electroantennogram (EAG) responses to a plant volatile compound, 3‐octanone, and methyl eugenol, whereas cue lure, raspberry ketone, and zingerone that are known to attract several other species of \nBactrocera fruit flies elicited no significant EAG responses from both sexes. In contrast, maxillary palps, housing one morphological type of basiconic sensilla, displayed the largest electropalpogram (EPG) responses to cue lure followed by raspberry ketone among the five compounds tested in male and female \nB. scutellata, with only minor EPG responses to 3‐octanone, which indicates that the maxillary palps are responsible for detecting cue lure and raspberry ketone in this species. In field trapping experiments, significant number of male \nB. scutellata were captured in the traps baited with cue lure or raspberry ketone, in which the attractiveness of cue lure was significantly higher than that of raspberry ketone. Methyl eugenol and zingerone were not behaviorally attractive to \nB. scutellata although they elicited significant EPG responses. Our study indicates that the behavioral attraction of \nB. scutellata to cue lure and raspberry ketone is mediated by the olfactory sensory neurons present in the maxillary palps.\n" - 'Archives of Insect Biochemistry and Physiology, Volume 99, Issue 4, December 2018. '
    November 16, 2018   doi: 10.1002/arch.21510   open full text
  • An investigation of the molecular and biochemical basis underlying chlorantraniliprole‐resistant Drosophila strains and their cross‐resistance to other insecticides.
    A‐Young Kim, Deok Ho Kwon, In Hong Jeong, Young Ho Koh.
    Archives of Insect Biochemistry and Physiology. November 16, 2018
    --- - "\n\n\n\n\n\nAbstract\nChlorantraniliprole is an anthranilic diamide insecticide that binds to the insect ryanodine receptor (RyR) and induces an uncontrolled release of Ca2+, resulting in paralysis and ultimately death of the target insects. Recently, it was reported that chlorantraniliprole‐resistant diamondback moths, \nPlutella xylostella Linnaeus, have mutations in their RyR. In this study, we developed two different chlorantraniliprole‐resistant \nDrosophila melanogaster strain. The resistance ratio (RR) of the low‐concentration chlorantraniliprole‐treated resistant (Low‐Res) strain was 2.3, while that of the high‐concentration chlorantraniliprole‐treated resistant (High‐Res) strain was 21.3. The LC\n50 of the untreated control (Con) strain was 23.8~25.9 ppm, which was significantly higher than that reported for the susceptible diamondback moth (0.03~0.51 ppm). The high LC\n50 of the Con may be because the helix S2 amino acid sequence of \nD. melanogaster RyR (\nDmRyR) is identical to the I4790M mutation of the chlorantraniliprole‐resistant diamondback moths, resulting in a lower binding affinity of \nDmRyR for chlorantraniliprole. Among the tested detoxification enzymes, the activity of esterase was significantly increased in the two Res strains, but glutathione \nS‐transferases and acetylcholinesterase were significantly decreased in the two Res strains. The cross‐resistance of the High‐Res strain to other insecticides with different modes of actions (MoAs) revealed that the RRs of the neuronal acetylcholine receptor allosteric and competitive modulators were significantly increased, while those of the Na\n2+ channel modulators were significantly reduced. Our studies showed that RRs against the same insecticide vary with the treatment concentration, and that RRs against other insecticides with different MoAs can be altered." - 'Archives of Insect Biochemistry and Physiology, Volume 99, Issue 4, December 2018. '
    November 16, 2018   doi: 10.1002/arch.21514   open full text
  • Degradation of sex pheromone and plant volatile components by an antennal glutathione S‐transferase in the oriental fruit moth,Grapholita molesta Busck (Lepidoptera: Tortricidae).
    Guang‐Wei Li, Xiu‐Lin Chen, Xiang‐Li Xu, Jun‐Xiang Wu.
    Archives of Insect Biochemistry and Physiology. November 16, 2018
    --- - |2- Abstract Insect antennae have a primary function of perceiving and discerning odorant molecules including sex pheromones and host plant volatiles. The assumption that genes highly expressed in the antennae may have an olfactory‐related role associated with signal transduction. Here, one delta subfamily glutathione S‐transferase (GST) gene (GmolGSTD1) was obtained from an antennal transcriptome of Grapholita molesta. Quantitative real‐time polymerase chain reaction results revealed that GmolGSTD1 was mainly expressed in antennae and the expression levels were significantly higher in female antennae than in male antennae. The recombinant GmolGSTD1 (rGmolGSTD1) showed glutathione‐conjugating activity toward 1‐chloro‐2,4‐dinitrobenzene (CDNB) as substrates. The pH range for optimal rGmolGSTD1 enzyme activity was 6.0–6.5, and rGmolGSTD1 enzyme activity had maximal peaks at 35–40°C. Spectrophotometric analysis indicated that insecticides had weak inhibitory effects on the activity of rGmolGSTD1 with the inhibitory rates of 28.82% for chlorpyrifos, 22.27% for lambda‐cyhalothrin, 18.07% for bifenthrin, 20.42% for acetamiprid, 17.57% for thiamethoxam, 25.67% for metaflumizone, 27.43% for abamectin, and 7.24% for chlorbenzuron. rGmolGSTD1 exhibited high degradation activity to the sex pheromone component (Z)‐8‐dodecenyl alcohol and the host plant volatile butyl hexanoate with the degradation efficiency of 75.01% and 48.54%, respectively. We speculate that GmolGSTD1 works in inactivating odorant molecules and maintaining sensitivity to olfactory communication of G. molesta. - 'Archives of Insect Biochemistry and Physiology, Volume 99, Issue 4, December 2018. '
    November 16, 2018   doi: 10.1002/arch.21512   open full text
  • Molecular cloning and functional analysis of small heat shock protein 19.1 gene from the Chinese oak silkworm, Antheraea pernyi.
    Jiawei Zhang, Qingqing Li, Yu Sun, Jiwu Tian, Zaijin Hu, Baojian Zhu, Chaoliang Liu.
    Archives of Insect Biochemistry and Physiology. November 16, 2018
    --- - "\nA small heat shock protein 19.1 gene was involved in the innate immunity and thermal stress response of the Chinese oak silkworm, Antheraea pernyi\n\n\n\n\n\nAbstract\nSmall heat shock proteins (sHSPs) are a class of highly conserved proteins that are ubiquitously found in all types of organisms, from prokaryotes to eukaryotes. In the current study, we identified and characterized the full‐length cDNA encoding sHSP 19.1 from the oak silkworm, \nAntheraea pernyi. Ap‐sHSP is 510 bp in length, and encodes a protein of 169 amino acid residues. The protein contains conserved domains found in insect sHSPs, and it belongs to the \nα‐crystallin‐HSPs_p23‐like superfamily. Recombinant Ap‐sHSP was expressed in \nEscherichia coli cells, and a rabbit anti‐Ap‐sHSP 19.1 antibody was generated to confirm the biological functions of \nAp‐sHSP 19.1 in \nA. pernyi. Real‐time polymerase chain reaction and western blot analysis revealed that \nAp‐sHSP 19.1 expression was highest in the fat body, followed by the midgut, and the lowest expression was found in the Malpighian tubule. \nAp‐sHSP 19.1 transcript expression was significantly induced following challenge with microbial pathogens. In addition, the expression of \nAp‐sHSP 19.1 was strongly induced after heat shock. These results suggest that \nAp‐sHSP 19.1 plays a crucial role in immune responses and thermal tolerance in \nA. pernyi." - 'Archives of Insect Biochemistry and Physiology, Volume 99, Issue 4, December 2018. '
    November 16, 2018   doi: 10.1002/arch.21516   open full text
  • Variation in the cuticular hydrocarbons of the Mexican fruit fly Anastrepha ludens males between strains and age classes.
    Carlos‐Felipe Bosa, Leopoldo Cruz‐López, Karina Guillén‐Navarro, Cristina Silvia Zepeda‐Cisneros, Pablo Liedo.
    Archives of Insect Biochemistry and Physiology. November 16, 2018
    --- - |2- Biplot of the representative two canonical dimensions within strains and CHCs of Anastrepha ludens males. Small circles indicate variability of the data, crossed circles (centroids) represent the mean for each strain. C = compound. Abstract In this study cuticular hydrocarbons (CHCs) were characterized from wings of individual unmated males of different Anastrepha ludens (Loew) mass‐reared strains of different ages (3 and 19‐day‐old): (a) a standard mass‐reared colony (control), (b) a genetic sexing strain, (c) a selected strain, (d) a hybrid strain, and (e) wild males. We found that the hydrocarbon profiles in all males included two n‐alkanes, five monomethyl alkanes, and two alkenes. CHCs ranged from C26 to C31. The most prominent peaks were 2‐methyloctacosane (2‐Me‐C28), n‐nonacosene (C29:1), 2‐methyltriacontane (2‐Me‐C30), and n‐hentriacontene (C31:1). Significant variations in the CHC amounts of the mass‐reared strains were observed from Day 9 and thereafter. Comparison of CHCs using multivariate and canonical analyses across ages and among mass‐reared strains and wild males revealed qualitative and quantitative differences. The relative amounts of C29:1 and 2‐Me‐C30 were significantly higher across age groups in the mass‐reared strains than those in the wild males. In contrast, amounts of n‐nonacosane (C29) significantly increased in wild males as they aged. Through statistical analyses, we inferred that CHC amounts vary with age. Wild males differed significantly from the mass‐reared strains in the amount of C29, and the genetic sexing strain Tap‐7 had significantly higher values for 2‐methylhexacosane (2‐Me‐C26). In contrast the selected and control strain differed from the other strains in amounts of C29:1 and 2‐Me‐C30. We suggest that differential profiles in hydrocarbon composition among the strains may be mainly due to environmental pressures. - 'Archives of Insect Biochemistry and Physiology, Volume 99, Issue 4, December 2018. '
    November 16, 2018   doi: 10.1002/arch.21513   open full text
  • Evaluation of the attractant effect and lipid profile modulation of natural fixed oils on the medfly Ceratitis capitata (Wiedemann).
    Antonella Rosa, Alessandra Piras, Gianfranca Carta, Paolo Solari, Roberto Crnjar, Carla Masala.
    Archives of Insect Biochemistry and Physiology. November 16, 2018
    --- - |2- Several fixed oils obtained by SFE‐CO2 extraction were tested in Ceratitis capitata. Oil attractant effect was tested by behavioral assays and related to oil composition. Myristica fragrans butter emerged as the most attractant on medflies among fixed oils. Changes in fatty acid profile of medflies fed (for 24 h) on fixed oils were evaluated. Our results will be potentially useful in developing new pest management strategies. Abstract The Mediterranean fruit fly, Ceratitis capitata (Wiedemann, 1824; Diptera: Tephritidae), is a polyphagous pest in horticulture, mainly targeting Citrus fruits. Natural essential and fixed oils are currently under investigation for their broad‐spectrum in pest control. To gain better knowledge about medfly behavior and biochemistry, we examined with behavioral and biochemical assays, the effects on C. capitata from six natural fixed oils obtained from vegetable (five) or animal (one) matrices using the eco‐friendly supercritical CO 2 extraction. Oils were obtained at 250/300 bar and 40°C from the seeds of Laurus nobilis and Citrus paradisi, the fruits of Myristica fragrans and Pistacia terebinthus, wheat germ, and mullet roes (marine oil). Behavioral experiments were performed by means of two‐choice tests to analyze the oil attractant effect compared with control (water or standard diet). The fatty acid composition of oils and the total lipid and fatty acid profile of medflies were characterized by chromatographic techniques. Behavioral bioassays showed that fixed oil obtained from M. fragrans (nutmeg butter) was more attractive than other oils. Medflies fed (24 hr) on marine oil showed significant changes in the total lipid and fatty acid profile induced by oil ingestion without toxic effects. However, 56% mortality was observed in insects fed on M. fragrans oil and no biochemical changes ascribable to oil ingestion were detected in the medflies that survived. Our results advance knowledge about the behavioral and biochemical response of medflies to fixed oils and will be potentially useful in developing new pest management strategies. - 'Archives of Insect Biochemistry and Physiology, Volume 99, Issue 4, December 2018. '
    November 16, 2018   doi: 10.1002/arch.21508   open full text
  • Eicosanoid mediation of immune responses at early bacterial infection stage and its inhibition by Photorhabdus temperata subsp. temperata, an entomopathogenic bacterium.
    Hyoil Kim, Duyeol Choi, Jihyeon Jung, Yonggyun Kim.
    Archives of Insect Biochemistry and Physiology. November 16, 2018
    --- - |2 Abstract An entomopathogenic bacterium Photorhabdus temperata subsp. temperata (Ptt) infects insect hemocoel by the vectoring activity of its symbiotic nematode, Heterorhabditis megidis. The bacterium induces host immunosuppression by inhibiting eicosanoid biosynthesis. This study investigated the role of eicosanoids in immune responses of the beet armyworm, Spodoptera exigua, in the early bacterial infection stage (first 3 hr postinfection [PI]). After infection with the nonpathogenic Escherichia coli (Ec), the bacterium maintained its population for the first 3 hr PI, then rapidly decreased in numbers. During the 3 hr PI of Ptt, this pathogenic bacterium also did not show any significant change in bacterial population. However, Ptt rapidly increased its population size after the initial lag phase, inducing fatal septicemia. This study further analyzed cellular and humoral immune responses of the beet armyworm during the initial 3 hr PI. During this early stage, challenge with Ec stimulated hemocyte‐spreading behavior along with extensive F‐actin growth. However, Ptt infection suppressed hemocyte spreading. Expression levels of three antimicrobial peptides (lysozyme, gloverin, and gallerimycin) were significantly inhibited during Ptt infection. Phospholipase A2 activity was significantly induced during the early infection stage of Ec, but not during Ptt infection. Addition of eicosanoid biosynthesis inhibitors significantly reversed the initial immunosuppression. These results suggest that, during the early infection stage, Ptt can shutdown eicosanoid biosynthesis which can prevent acute immune responses of host insects. - 'Archives of Insect Biochemistry and Physiology, Volume 99, Issue 4, December 2018. '
    November 16, 2018   doi: 10.1002/arch.21502   open full text
  • The contribution of gustatory input to larval acceptance and female oviposition choice of potential host plants in Papilio hospiton (Géné).
    Giorgia Sollai, Roberto Crnjar.
    Archives of Insect Biochemistry and Physiology. November 12, 2018
    --- - "\nAdults females of P. hospiton only lay eggs on \nFerula communis and larvae only feed on the same plant. The different pattern of activity of GRNs evoked by plant saps allows both females and larvae to discriminate among them (accepting ferula as host and rejecting fennel and carrot) thus strengthening the theory that the peripheral taste sensitivity plays a key role in host acceptance or rejection, and in the discrimination process between host and nonhost plants.\n\n\n\n\n\n\nAbstract\nThe Lepidopteran Papilio hospiton uses only plants belonging to the Apiaceae and the Rutaceae families as hosts. Both adult females and larvae are equipped with gustatory receptor neurons (GRNs) capable of detecting sugars, bitters and salts, thus providing information for evaluating the chemical composition of the plant. Since the activation of these neurons may affect insect behavior, the aim of this study were: (a) to study the gustatory sensitivity of both females and larvae to the sap of two Apiaceae, \nFoeniculum vulgare (fennel) and \nDaucus carota (carrot), that are not used as host plants; (b) to cross‐compare the spike activity evoked from these two plants with that evoked by \nFerula communis (ferula), the host plant preferred by ovipositing females of \nP. hospiton and where the larvae perform best; (c) finally, to confirm that the gustatory system can provide the central nervous system with the necessary information to evaluate differences between plant saps. The results show that: (a) fennel and carrot both evoke a higher neural activity from the bitter‐sensitive neurons and lower from the sugar‐sensitive neurons with respect to ferula, in both adult females and larvae; (b) on the basis of the different patterns of neural activity generated in tarsal, lateral and medial sensilla by fennel and carrot versus ferula, both adult and larvae possess enough information to discriminate among these plants; (c) adult females of \nP. hospiton lay eggs where the larvae have the greatest growth success and this confirms the importance of taste sensitivity in host plants selection." - 'Archives of Insect Biochemistry and Physiology, EarlyView. '
    November 12, 2018   doi: 10.1002/arch.21521   open full text
  • Three vital RNA functions and interactions in the process of silk gland apoptosis in silkworm Bombyx mori.
    Rui‐Ting Chen, Ying Xiao, Zhen Liu, Lei‐Lei Li, Yan Lu, Peng Jiao, Yun‐Gen Miao.
    Archives of Insect Biochemistry and Physiology. November 11, 2018
    --- - "\n\n\n\n\n\n\nAbstract\nThe Silkworm Bombyx mori is an important insect in terms of economics and a model organism with a complete metamorphosis. The economic importance of silkworms is dependent on the functions of the silkgland, a specialized organ that synthesizes silk proteins. The silk gland undergoes massive degeneration during the larval to pupal stage, which involves in cell apoptosis. In this paper, high throughput sequencing was used to detect the expression of messenger RNA (mRNA), long noncoding RNA (lncRNA), and microRNA (miRNA) from silk glands of Day 3 in the fifth instar larvae (L5D3) and the spinning 36h (sp36h). We analyzed the Gene Ontology (GO) functions of target genes of the differentially expressed lncRNAs and miRNAs. We investigated the regulations of mRNA, lncRNA, and miRNA on silk gland apoptosis in L5D3 and sp36h. In total, 10,947 lncRNAs were detected in the silk gland and the index number TCONS‐00021360 lncRNA may be involved in the process of apoptosis. In addition, 344 miRNAs targeted 285 mRNAs were related to the death process under GO entry. The results indicated that miRNAs play an important role in the molecular regulation of the silk gland apoptosis compared with that of lncRNAs. Finally, we screened 746 lncRNAs and 20 miRNAs that might interact with \nBmDredd, and drew an interaction network among them." - 'Archives of Insect Biochemistry and Physiology, EarlyView. '
    November 11, 2018   doi: 10.1002/arch.21511   open full text
  • Repellent action and contact toxicity mechanisms of the essential oil extracted from Chinese chive against Plutella xylostella larvae.
    Quan Gao, Li Song, Jia Sun, Hai‐Qun Cao, Likun Wang, Huafeng Lin, Feng Tang.
    Archives of Insect Biochemistry and Physiology. November 02, 2018
    --- - "\nAbstract\nBotanical pesticides play increasingly important roles in the control of agricultural pests. In this study, the insecticidal effects, specifically the repellent action and contact toxicity, of the essential oil extracted from Chinese chive (EOC) against Plutella xylostella larvae were confirmed. The mechanisms of repellent’s action were studied using electroantennograms (EAGs), and the effects on glutathione \nS‐transferase (GST), carboxylesterase (CarE), and acetyl cholinesterase were investigated after EOC treatments. The EOC affected the EAG results and inhibited the activities of GST and CarE in treated \nP. xylostella larvae, which could explain its insecticidal effects. And, four pyrazines showed greater repellent activities than that of the EOC, which was confirmed as the main active compounds of EOC." - 'Archives of Insect Biochemistry and Physiology, EarlyView. '
    November 02, 2018   doi: 10.1002/arch.21509   open full text
  • Issue Information.

    Archives of Insect Biochemistry and Physiology. September 26, 2018
    --- - - Archives of Insect Biochemistry and Physiology, Volume 99, Issue 2, October 2018.
    September 26, 2018   doi: 10.1002/arch.21418   open full text
  • Inhibition of silkworm vacuolar‐type ATPase activity by its inhibitor Bafilomycin A1 induces caspase‐dependent apoptosis in an embryonic cell line of silkworm.
    Xiao‐Yin Tan, Xin Wang, Qing‐Song Liu, Xiao‐Qian Xie, Yi Li, Bing‐Qian Li, Zhi‐Qing Li, Qing‐You Xia, Ping Zhao.
    Archives of Insect Biochemistry and Physiology. September 24, 2018
    --- - "\nAbstract\nVacuolar‐type ATPase (V‐ATPase) is a type of hydrogen ion transporter located in the vesicular membrane‐like system, which mediates active transport and intracellular acidification in various compartments. In mammals, V‐ATPase has been reported to play a key role in cell proliferation and apoptosis. The studies of V‐ATPase in silkworm mainly focus on the acidification regulation of midgut and silk gland and immune resistance. However, there are few reports about the function of silkworm V‐ATPase on cell proliferation, autophagy, and apoptosis. Thus, the function of V‐ATPase in a cell line of Bombyx mori (BmE) was investigated by treating the cell line with bafilomycin A1, a specific inhibitor of V‐ATPase. Cell counting kit 8 (CCK8) and flow cytometry analysis showed that bafilomycin A1 treatment decreased the cell proliferation activity, affected the cell cycle progression and induced cell apoptosis. LysoTracker Red staining showed that the target of bafilomycin A1 is lysosome. The expression of all autophagy‐related genes (\nBmATG5, \nBmATG6, and \nBmATG8) decreased, indicating that cell autophagy was inhibited. The analysis of the apoptosis pathway demonstrated that inhibiting the activity of V‐ATPase of BmE cells could promote mitochondria to release cytochrome C, inhibit the expression of \nBmIAP, and activate the caspase cascade to induce apoptosis. All these findings systematically illustrate the effects of V‐ATPase on the proliferation, autophagy, and apoptosis in BmE cells, and provide new ideas and a theoretical basis for further study on the function of V‐ATPase in BmE." - Archives of Insect Biochemistry and Physiology, EarlyView.
    September 24, 2018   doi: 10.1002/arch.21507   open full text
  • Development of a highly accurate and sensitive diagnostic tool for pyrethroid‐resistant chimeric P450 CYP337B3 of Helicoverpa armigera using loop‐mediated isothermal amplification.
    Bo Hey Choi, Joon Haeng Hur, David G. Heckel, Juil Kim, Young Ho Koh.
    Archives of Insect Biochemistry and Physiology. September 15, 2018
    --- - |2- Abstract Recent studies have shown that pyrethroid resistance in the cotton bollworm (CBW) Helicoverpa armigera is conferred by the generation of a chimeric CYP337B3 gene, which resulted from unequal crossing‐over between the CYP337B1 and CYP337B2 genes. In this study, we developed a diagnostic protocol based on the loop‐mediated isothermal amplification (LAMP) assay for the detection of chimeric CYP337B3. The CYP337B3 LAMP assay utilized six primers and generated strong fluorescence signals visible to the naked eye under normal or ultraviolet light. The primers were designed based on CYP337B3v1 (JQ995292), the major allele detected in Australia. The detection limit of this LAMP assay was 10 fg genomic DNA in a 25‐µl reaction mixture. Compared with CYP337B2v1, the Korean CYP337B3v2 allele had two nucleotide mismatches within the amplifying regions of this LAMP assay; therefore, we confirmed that polymerase chain reaction‐synthesized CYP337B3v2 was well amplified using this LAMP assay. In addition, we determined that the presence of CYP337B3 from H. armigera collected by pheromone traps from Korean fields could be confirmed using this LAMP assay. This assay could detect CYP337B3 even in heterozygotes, which is relevant because CYP337B3 is dominant, and heterozygotes are pyrethroid resistant. Therefore, the newly developed CYP337B3 LAMP assay could detect the presence of pyrethroid resistance in H. armigera that were captured by pheromone traps during the early season and provide information on whether pyrethroids could be used to control H. armigera. - Archives of Insect Biochemistry and Physiology, EarlyView.
    September 15, 2018   doi: 10.1002/arch.21504   open full text
  • Molecular identification of sterol regulatory element‐binding protein‐1c from Helicoverpa armigera pheromone gland.
    Yunhui Zhang, Nana Ma, Letong Yin, Jizhen Wei, Yuqiang Xi, Xincheng Zhao, Mengfang Du, Shiheng An.
    Archives of Insect Biochemistry and Physiology. September 11, 2018
    --- - |2- Abstract Sterol regulatory element‐binding protein‐1c (SREBP‐1c) is a basic helix‐loop‐helix type transcription factor that regulates the fatty acid and cholesterol biosynthesis. Lepidoptera sex pheromone is a product of fatty acid biosynthesis followed by carbon chain modifications. However, the role of SREBP‐1c on sex pheromone biosynthesis remains elusive. In the present study, Helicoverpa armigera was used as a model to investigate the role of SREBP‐1c on sex pheromone biosynthesis (HaSREBP‐1c). Sequence analysis demonstrated that the open reading frame of HaSREBP‐1c consists of 3201 bp nucleotides that encode 1066 amino acid residues. Blast searches based on amino acid sequences demonstrated that HaSREBP‐1c shares higher amino acid identity with lepidopteran homologues. Development expression profiles demonstrated that HaSREBP‐1c transcript could be detected at 72 hr before adult emergence, then gradually increased, and finally reached its peak at 24 hr after adult emergence. The spatial expression pattern demonstrated that HaSREBP‐1c was ubiquitously expressed in all examined tissues. The decrease of HaSREBP‐1c messenger RNA (mRNA) levels as shown by RNA interference caused significant decreases in acetyl‐coA carboxylase (ACC) mRNA levels and subsequent sex pheromone production. Behavior analysis demonstrated that the decrease of HaSREBP‐1c mRNA level caused a significant decrease in the female’s ability to attract males. Altogether our results demonstrated that HaSREBP‐1c acts as a transcription factor to regulate ACC mRNA expression and, therefore, to influence female sex pheromone biosynthesis. - Archives of Insect Biochemistry and Physiology, EarlyView.
    September 11, 2018   doi: 10.1002/arch.21505   open full text
  • Identification and characterization of capa and pyrokinin genes in the brown marmorated stink bug, Halyomorpha halys (Hemiptera): Gene structure, immunocytochemistry, and differential expression.
    Seung‐Joon Ahn, Man‐Yeon Choi.
    Archives of Insect Biochemistry and Physiology. September 06, 2018
    --- - "\nAbstract\nCAPA and pyrokinin (PK) neuropeptides are produced from two different genes, capa and \npyrokinin, respectively. In this study, we identified and characterized the \ncapa and \npyrokinin genes from the brown marmorated stink bug, \nHalyomorpha halys (Hemiptera). The \ncapa gene encodes two CAPA‐PVK (periviscerokinin) peptides (DAGLFPFPRVamide and EQLIPFPRVamide) and one CAPA‐DH (diapause hormone; NGASGNGGLWFGPRLamide). The \npyrokinin gene encodes three PK2 peptides (QLVSFRPRLamide, SPPFAPRLamide, and FYAPFSPRLamide). The whole‐mounting immunocytochemistry revealed the neurons contained PRXamide‐like peptides throughout the cerebral ganglia (CRG), gnathal ganglia (GNG), thoracic ganglia (TG), and abdominal ganglia (AG). A pair of neurosecretory cells in the CRG and three cell clusters in the GNG were found with the axonal projections extended through the lateral side. A pair of immunostained cells were found in the TG, while three pairs of cells were present in the fused AG. Different expression patterns of \ncapa and \npyrokinin genes were observed in the CRG–GNG, TG, and AG. The \ncapa gene was highly expressed in the AG tissue, whereas the \npyrokinin gene was strongly expressed in the CRG–GNG. Interestingly, different developmental stages showed similar expressions of both genes, with the highest from the first nymph, gradually decreasing to the female adult. Comparison of peptide sequences encoded from \npyrokinin genes showed the PK1 peptide is lost in Heteroptera suborders including \nH. halys, but retained in other suborders. The missing PK1 from the \npyrokinin gene might be compensated by CAPA‐DH (=PK1‐like) produced by the \ncapa gene.\n" - Archives of Insect Biochemistry and Physiology, EarlyView.
    September 06, 2018   doi: 10.1002/arch.21500   open full text
  • Juvenile hormone affects the splicing of Culex quinquefasciatus early trypsin messenger RNA.
    Dov Borovsky, Robert G. Hancock, Pierre Rougé, Charles A. Powell, Robert G. Shatters.
    Archives of Insect Biochemistry and Physiology. September 03, 2018
    --- - "\nAbstract\nThe full length of Culex quiquefasciatus early trypsin has been cloned and sequenced and a three‐dimensional (3D) model of the enzyme was built showing that the enzyme has the canonical trypsin’s active pocket containing H78, D123, S129, and D128. The biosynthesis of juvenile hormone (JH) III by the corpora allata (CA) in female \nCx. quiquefasciatus is sugar‐dependent. Females that were maintained on water after emergence synthesize very little JH III, JH III bisepoxide, and methyl farnesoate (MF) (3.8, 1.1, and 0.8 fmol/4 hr/CA, respectively). One hour after sugar feeding, the synthesis of JH III and JH III bisepoxide reached a maximum (11.3 and 5.9 fmol/4 hr/CA, respectively) whereas MF biosynthesis reached a maximum at 24 hr (5.2 fmol/4 hr/CA). The early trypsin is transcribed with a short intron (51 nt) is spliced when JH III biosynthesis is high in sugar fed and at 1 hr after the blood meal (22 and 15  fmol/4 hr/CA, respectively). We investigated the transcriptional and posttranscriptional regulation of the early trypsin gene showing that JH III concentrations influence splicing. In the absence JH III the unspliced transcript is linked by a phosphoamide bond at the 5′‐end to RNA ribonuleoprotein (RNP). The biosynthesis of the early trypsin was followed in ligated abdomens (without CA) of newly emerged females that fed blood by enema. Our results show that the early trypsin biosynthesis depends on sugar and blood feeding, whereas the late trypsin biosynthesis does not depend on sugar feeding, or JH III biosynthesis. Downregulating the early trypsin transcript does not affect the late trypsin.\n" - Archives of Insect Biochemistry and Physiology, EarlyView.
    September 03, 2018   doi: 10.1002/arch.21506   open full text
  • Superoxide dismutase from venom of the ectoparasitoid Scleroderma guani inhibits melanization of hemolymph.
    Nai‐Yong Liu, Jing‐Mei Huang, Xue‐Min Ren, Zhi‐Wen Xu, Nai‐Sheng Yan, Jia‐Ying Zhu.
    Archives of Insect Biochemistry and Physiology. August 18, 2018
    --- - |2- Abstract Superoxide dismutase (SOD) known as an important antioxidative stress protein has been recently found in venoms of several parasitoid wasps. However, its functions and characteristics as a virulent factor remain scarcely described. Here, we report the characterization of two venomous SOD genes (SguaSOD1 and SguaSOD3) from the ectoparasitoid, Scleroderma guani. The metal binding sites, cysteine amino acid positions and signature sequences of the SOD family were conserved within SguaSOD1 and SguaSOD3. Relatively high levels of their transcripts were observed in pupae followed a decrease in early adults, after which they had the highest transcriptions, indicating that their productions would be regulated in venom apparatus. Although the two genes showed lower expression in venom apparatus compared to head and thorax, the enzymatic assay revealed that SOD indeed had activity in venom. Further, we showed that recombinant SguaSOD3 suppressed melanization of host hemolymph, implying that this protein used as a virulent factor uniquely impacts the prophenoloxidase cascade. - Archives of Insect Biochemistry and Physiology, EarlyView.
    August 18, 2018   doi: 10.1002/arch.21503   open full text
  • Culturable epiphytic bacteria isolated from Teleogryllus occipitalus crickets metabolize insecticides.
    Linling He, Bo Liu, Jiewei Tian, Fengjuan Lu, Xiaoguang Li, Yongqiang Tian.
    Archives of Insect Biochemistry and Physiology. August 17, 2018
    --- - |2- Abstract The development of insecticide resistance is attributed to evolutionary changes in pest insect genomes, such as alteration of drug target sites, upregulation of degrading enzymes, and enhancement of drug excretion. Beyond these well‐known mechanisms, symbiotic bacteria may confer insecticide resistance to host crickets. The current study was designed to screen all possible culturable bacterial groups found living in and on the bodies of Teleogryllus occipitalis crickets. We recovered 263 visible bacterial colonies and cultured them individually. After identifying the colonies based on morphology and phylogenetic analysis, we shortlisted 55 bacterial strains belonging to 28 genera. Of these 55 bacterial strains, 18 degraded at least 50% of the original amount of 400 mg/L chlorpyrifos (CP) after 24 hr of coculture. Six of these strains degraded more than 70% of the original amount of 400 mg/L CP. Three strains had antagonistic effects on Bacillus thuringiensis growth. Additionally, the ability of the isolates to degrade glyphosate, phoxim, and esfenvalerate was assessed. We also detected extracellular hydrolase enzyme activities in these isolates. We propose that epiphytic bacterial strains play multiple roles in cricket biology, one of which contributes to chemical and biological pesticide resistance. - Archives of Insect Biochemistry and Physiology, Volume 99, Issue 2, October 2018.
    August 17, 2018   doi: 10.1002/arch.21501   open full text
  • Properties of a novel carboxymethyl chitosan derived from silkworm pupa.
    Lin Zhu, De‐Qing Zou, Zuo‐Qing Fan, Na Wang, Ying‐Ying Bo, Yu‐Qing Zhang, Guang Guo.
    Archives of Insect Biochemistry and Physiology. August 04, 2018
    --- - |2- Abstract In this study, a carboxymethyl chitosan derived from silkworm pupa (SP‐carboxymethyl chitosan) was prepared. The physical characteristics of the SP chitin, chitosan, and carboxymethyl chitosan were analyzed. The scanning electron microscopy results showed that the surfaces of the samples from SP were more uneven, with more surface fractures compared with those of the reference substance (RS). Thermal analysis, X‐ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy analysis showed that the main molecular chain structures of SP samples and RSs had no substantial differences. However, the crystallinity and thermal decomposition temperature of the SP samples were lower compared with those of the RSs. All of these results provide a theoretical basis for the development of applications for the SP‐carboxymethyl chitosan. - Archives of Insect Biochemistry and Physiology, Volume 99, Issue 2, October 2018.
    August 04, 2018   doi: 10.1002/arch.21499   open full text
  • Influence of rearing temperature on triacylglycerol storage in the pea aphid, Acyrthosiphon pisum.
    Zhaorigetu Hubhachen, Robin D. Madden, Jack W. Dillwith.
    Archives of Insect Biochemistry and Physiology. July 12, 2018
    --- - |2 Abstract Total fatty acids in the pea aphid reared at low temperatures increased significantly compared to that at high rearing temperatures. This change is reflected in a large increase of myristic acid, which occurs exclusively in triacylglycerols. When aphids were moved from 25°C to a lower rearing temperature at 10°C, saturated fatty acids accumulated over time, reaching a maximum at 16th day. When aphids were moved to 4°C, a temperature below the developmental threshold, those aphids did not accumulate saturated fatty acids. Similar results were observed when aphids were exposed to sequential decrease in rearing temperature. However, both total fatty acids and myristic acid in the aphids from the treatments of sequential decreasing rearing temperature were significantly higher compared to those in the aphids from the treatments of sudden decreasing rearing temperature. This result, therefore, supports the hypothesis that cold‐adapted aphids can survive under threshold temperature for a longer period of time than noncold‐adapted aphids. Acetyl‐CoA carboxylase activity in the aphids at 25°C was twofold higher than that in the aphids at 10°C, whereas fatty acid synthase activities in the aphids reared at 25 and 10°C are similar. Aphids reared at 10°C showed a threefold reduction in reproduction rates. This reduced production of new nymphs reduces energy demand and would allow for accumulation of energy in the form of triacylglycerols. Therefore, the increased level of saturated fatty acids in aphids reared at low temperature is probably related to lower utilization of fatty acids rather than increased rates of biosynthesis. - Archives of Insect Biochemistry and Physiology, Volume 99, Issue 2, October 2018.
    July 12, 2018   doi: 10.1002/arch.21495   open full text
  • Crinkled employs wingless pathway for wing development in Tribolium castaneum.
    Chengjun Li, Yaoyao Lu, Shangshang Ma, Peng Lü, Bin Li, Keping Chen.
    Archives of Insect Biochemistry and Physiology. July 09, 2018
    --- - |2 Abstract Crinkled is associated with embryonic denticle formation and auditory organ development in Drosophila melanogaster. However, the functions of Crinkled have not been fully investigated. Additionally, the genes that participate in the Crinkled pathway are unknown. Phylogenetic analysis indicates that crinkled exhibits a one‐to‐one orthologous relationship in insects. In Tribolium castaneum, the crinkled gene is 6,498 bp in length and consists of six exons. Crinkled expression peaked during two phases in Tribolium: late embryonic and pupal stages. High levels of crinkled mRNA were detected in the fat body, head, epidermis, ovary, and accessory gland of late adults. Knockdown of crinkled using RNA interference (RNAi) severely affected wing morphogenesis in T. castaneum. We further showed that crinkled silencing reduced forked expression through wingless and shaven‐baby, and RNAi of forked phenocopied the effects of crinkled knockdown in T. castaneum. This study investigated the development role of crinkled in postembryonic stages and indicated that forked mediates the functions of crinkled during wing morphogenesis in T. castaneum. - Archives of Insect Biochemistry and Physiology, Volume 99, Issue 2, October 2018.
    July 09, 2018   doi: 10.1002/arch.21496   open full text
  • Aluminum toxicity related to SOD and expression of presenilin and CREB in Bombyx mori.
    Longhai Liu, Xiaoran Qian, Mengling Chao, Yijiao Zhao, Junyi Huang, Taichu Wang, Fan Sun, Erjun Ling, Hongsheng Song.
    Archives of Insect Biochemistry and Physiology. July 05, 2018
    --- - |2 Abstract Aluminum (Al) is an important environmental metal factor that can be potentially associated with pathological changes leading to neurotoxicity. The silkworm, Bombyx mori, is an important economic insect and has also been used as a model organism in various research areas. However, the toxicity of Al on silkworm physiology has not been reported. Here, we comprehensively investigate the toxic effects of Al on the silkworm, focusing on its effects on viability and development, superoxide dismutase (SOD) activity, and the expression of presenilin and cAMP response element‐binding protein (CREB) in BmE cells and silkworm larvae. BmE cell viability decreased after treatment with aluminum chloride (AlCl3) in both dose‐ and time‐dependent manners. When AlCl3 solution was injected into newly hatched fifth instar larvae, both larval weight gain and survival rate were significantly decreased in a manner correlating with AlCl3 dose and developmental stage. Furthermore, when BmE cells and silkworm larvae were exposed to AlCl3, SOD activity decreased significantly relative to the control group, whereas presenilin expression increased more than twofold. Additionally, CREB and phosphorylated CREB (p‐CREB) expression in the heads of fifth instar larvae decreased by 28.0% and 50.0%, respectively. These results indicate that Al inhibits the growth and development of silkworms in vitro and in vivo, altering SOD activity and the expressions of presenilin, CREB, and p‐CREB. Our data suggest that B. mori can serve as a model animal for studying Al‐induced neurotoxicity or neurodegeneration. - Archives of Insect Biochemistry and Physiology, Volume 99, Issue 2, October 2018.
    July 05, 2018   doi: 10.1002/arch.21480   open full text
  • Preventive effects of N‐acetyl‐l‐cysteine against imidacloprid intoxication on Bombyx mori larvae.
    Hui‐Ju Gao, Yong‐Liang Sun, Gui‐Zhen Song, Bin Su, Meng‐Meng Zhang, Chun‐Jiu Ren, Yan‐Wen Wang.
    Archives of Insect Biochemistry and Physiology. July 05, 2018
    --- - |2 Abstract Imidacloprid, a widely used neonicotinoid insecticide, is toxic to silkworm (Bombyx mori). To explore whether N‐acetyl‐l‐cysteine (NAC) has an effect on preventing silkworm (B. mori) from toxification caused by imidacloprid, we fed the fifth‐instar larvae with mulberry leaves dipped in 200 mg/L NAC solution before exposing in imidacloprid, and investigated the silkworm growth, survival rate, feed efficiency, cocoon quality, and the activities of antioxidant enzymes in midgut. The results showed that addition of NAC could significantly increase body weight, survival rate, and feed efficiency of imidacloprid poisoned silkworm larvae (P < 0.05), as well as cocoon mass, cocoon shell mass, and the ratio of cocoon shell (P < 0.05). Furthermore, it could significantly promote the activities of the antioxidant enzymes including superoxide dismutase, catalase, and glutathione peroxide in the midgut of fifth‐instar larvae under imidacloprid exposure at the late stage of treatment. In addition, it also could downregulate the malondialdehyde content. The results of our findings proved that the added NAC may have some beneficial effects on protection or restoration of antioxidant balance in imidacloprid exposed larvae. - Archives of Insect Biochemistry and Physiology, Volume 99, Issue 2, October 2018.
    July 05, 2018   doi: 10.1002/arch.21497   open full text
  • Brummer‐dependent lipid mobilization regulates starvation resistance in Nilaparvata lugens.
    Jinming Zhou, Xia Chen, Jing Yan, Keke You, Zhineng Yuan, Qiang Zhou, Kai Lu.
    Archives of Insect Biochemistry and Physiology. June 28, 2018
    --- - |2 Abstract Energy homeostasis is an essential characteristic of all organisms, requiring fluctuation in energy accumulation, mobilization, and exchange with the external environment. In insects, energy mobilization is under control of the lipase brummer (bmm), which regulates nutritional status by hydrolyzing the ester bonds in triacylglycerol (TAG). In the present study, we investigated the role of bmm in the lipid mobilization and starvation resistance in the brown planthopper (BPH; Nilaparvata lugens), which is economically one of the most important rice pests in Asia. A severe decrease in TAG and glyceride contents was observed in the starved BPHs, while there was a partial rescue after refeeding. The starvation condition caused a significant increase in the expression levels of Nlbmm, and supplement of food after starvation dramatically reduced the Nlbmm expression. Sucrose rescue after starvation significantly suppressed the expression of Nlbmm, while caused an accumulation of TAG and glyceride. Knockdown of Nlbmm by double‐stranded RNA treatment extended the lifespan to starvation, whereas it increased the level of TAG and glyceride in the BPHs. The decreased lipolysis rate by dsNlbmm‐treated BPHs eventually resulted in increase of starvation resistance. These data demonstrated that the regulation of energy homeostasis by Nlbmm affects starvation resistance, probably through lipid mobilization control in N. lugens. - Archives of Insect Biochemistry and Physiology, Volume 99, Issue 2, October 2018.
    June 28, 2018   doi: 10.1002/arch.21481   open full text
  • Sterol content in the artificial diet of Mythimna separata affects the metabolomics of Arma chinensis (Fallou) as determined by proton nuclear magnetic resonance spectroscopy.
    Yi Guo, Chen‐xi Liu, Li‐sheng Zhang, Meng‐qing Wang, Hong‐yin Chen.
    Archives of Insect Biochemistry and Physiology. October 11, 2017
    Insects cannot synthesize sterols and must obtain them from plants. Therefore, reducing plant sterol content or changing sterol type might be an effective pest control strategy. However, the impacts of these changes on pests’ natural predators remain unknown. Here, we fed artificial diets with reduced sterol content to Mythimna separata (Walker) (Lepidoptera: Noctuidae) and investigated the effects on its natural predator, Arma chinensis (Fallou) (Hemiptera: Pentatomidae). Reduced sterol content in M. separata (MS1, MS2, and MS5) was achieved by feeding them artificial diets prepared from a feed base subjected to one, two, or five cycles of sterol extractions, respectively. The content of most substances increased in A. chinensis (AC) groups feeding on MS2 and MS5. The content of eight substances (alanine, betaine, dimethylamine, fumarate, glutamine, glycine, methylamine, and sarcosine) differed significantly between the control (AC0) and treated (AC1, AC2, and AC5) groups. Metabolic profiling revealed that only AC5 was significantly distinct from AC0; the major substances contributing to this difference were maltose, glucose, tyrosine, proline, O‐phosphocholine, glutamine, allantoin, lysine, valine, and glutamate. Furthermore, only two metabolic pathways, that is, nicotinate and nicotinamide metabolism and ubiquinone and other terpenoid‐quinone biosynthesis, differed significantly between AC1 and AC5 and the control, albeit with an impact value of zero. Thus, the sterol content in the artificial diet fed to M. separata only minimally affected the metabolites and metabolic pathways of its predator A. chinensis, suggesting that A. chinensis has good metabolic self‐regulation with high resistance to sterol content changes.
    October 11, 2017   doi: 10.1002/arch.21426   open full text
  • Proteomic analysis of the venom of the predatory ant Pachycondyla striata (Hymenoptera: Formicidae).
    Pollyanna Pereira Santos, Patricia Dias Games, Dihego Oliveira Azevedo, Edvaldo Barros, Leandro Licursi Oliveira, Humberto Josué Oliveira Ramos, Maria Cristina Baracat‐Pereira, José Eduardo Serrão.
    Archives of Insect Biochemistry and Physiology. October 10, 2017
    The ants use their venom for predation, defense, and communication. The venom of these insects is rich in peptides and proteins, and compared with other animal venoms, ant venoms remain poorly explored. The objective of this study was to evaluate the protein content of the venom in the Ponerinae ant Pachycondyla striata. Venom samples were collected by manual gland reservoir dissection, and samples were submitted to two‐dimensional gel electrophoresis and separation by ion‐exchange and reverse‐phase high‐performance liquid chromatography followed by mass spectrometry using tanden matrix‐assisted laser desorption/ionization with time‐of‐flight (MALDI‐TOF/TOF) mass spectrometry and electrospray ionization‐quadrupole with time‐of‐flight (ESI‐Q/TOF) mass spectrometry for obtaining amino acid sequence. Spectra obtained were searched against the NCBInr and SwissProt database. Additional analysis was performed using PEAKS Studio 7.0 (Sequencing de novo). The venom of P. striata has a complex mixture of proteins from which 43 were identified. Within the identified proteins are classical venom proteins (phospholipase A, hyaluronidase, and aminopeptidase N), allergenic proteins (different venom allergens), and bioactive peptides (U10‐ctenitoxin Pn1a). Venom allergens are among the most expressed proteins, suggesting that P. striata venom has high allergenic potential. This study discusses the possible functions of the proteins identified in the venom of P. striata.
    October 10, 2017   doi: 10.1002/arch.21424   open full text
  • Identification of three prophenoloxidase‐activating factors (PPAFs) from an invasive beetle Octodonta nipae Maulik (Coleoptera: Chrysomelidae) and their roles in the prophenoloxidase activation.
    HuaJian Zhang, BaoZhen Tang, YaPing Lin, ZhiMing Chen, XiaFang Zhang, TianLiang Ji, XiaoMei Zhang, YouMing Hou.
    Archives of Insect Biochemistry and Physiology. October 08, 2017
    A typical characteristic of the insect innate immune system is the activation of the serine protease cascade in the hemolymph. As being the terminal component of the extracellular serine protease cascade in the prophenoloxidase (proPO) activating system, proPO‐activating factors (PPAFs) activated by the upstream cascade may generate active phenoloxidase, which then induces downstream melanization. In the present study, we reported three PPAFs from the nipa palm hispid beetle Octodonta nipae (Maulik) (designated as OnPPAF1, OnPPAF2, OnPPAF3). All three OnPPAFs contained a single clip domain at the amino‐terminus followed by a trypsin‐like serine protease domain at the carboxyl‐terminus, except the Ser in the active sites of OnPPAF2 and OnPPAF3 was substituted with Gly. Transcript expression analysis revealed that all OnPPAFs were highly expressed in hemolymph, whereas OnPPAF2 showed an extremely low mRNA abundance compared with that of OnPPAF1 and OnPPAF3, and that the abundance of all three OnPPAFs was dramatically increased upon bacterial challenge. Knockdown of OnPPAF1 or OnPPAF3 resulted in a reduction of hemolymph phenoloxidase activity and an inhibition of hemolymph melanization, whereas the knockdown of OnPPAF2 did not affect the proPO cascade. Our work thus implies that the three OnPPAFs may have different functions and regulation during immune responses in O. nipae.
    October 08, 2017   doi: 10.1002/arch.21425   open full text
  • Inhibition of translation initiation factor eIF4A is required for apoptosis mediated by Microplitis bicoloratus bracovirus.
    Shu‐Mei Dong, Ji‐Hui Cui, Wei Zhang, Xue‐Wen Zhang, Tian‐Chao Kou, Qiu‐Chen Cai, Sha Xu, Shan You, Dong‐Shuai Yu, Lei Ding, Jian‐Hua Lai, Ming Li, Kai‐Jun Luo.
    Archives of Insect Biochemistry and Physiology. September 20, 2017
    Apoptotic hemocytes induced by Microplitis bicoloratus parasitism have been reported, and M. bicoloratus bracovirus (MbBV) is known to be the apoptosis inducer. However, the mechanism how MbBV regulates apoptosis remains unclear. eIF4A, one of translation initiation factors, was found from a Spodoptera litura transcriptome, the expression of which in the parasitized hemocytes of S. litura was inhibited in RT‐qPCR analysis. The western blot also illustrated eIF4A at 6‐day post‐parasitization was inhibited in hemocytes. For testing interaction of MbBV–eIF4A–apoptosis, a cDNA clone encoding 1,266 bp of eIF4A was obtained from S. litura hemocytes and sequenced. Then, a 48 kDa V5‐fusion protein of the eIF4A was detected by using the anti‐V5 antibody at 72‐h post‐transfection in the High Five cells, which is located in the cell cytoplasm. In vitro, overexpression of eIF4A rescued the apoptotic High Five cells induced by MbBV. Conversely, in vivo, loss of eIF4A proteins by dsRNA feeding increased apoptosis of hemocytes. Furthermore, RNAi and parasitism significantly increased apoptosis of hemocytes in S. litura. These findings suggested that MbBV inhibited the expression of eIF4A, which was required for apoptosis mediated by MbBV. This study will contribute to biological pest control and enhance our understanding of molecular mechanisms underlying polydnavirus–parasitoid–host interaction.
    September 20, 2017   doi: 10.1002/arch.21423   open full text
  • Differences in protein expression among five species of stream stonefly (Plecoptera) along a latitudinal gradient in Japan.
    Maribet Gamboa, Maria Claret Tsuchiya, Suguru Matsumoto, Hisato Iwata, Kozo Watanabe.
    Archives of Insect Biochemistry and Physiology. September 19, 2017
    Proteome variation among natural populations along an environmental gradient may provide insights into how the biological functions of species are related to their local adaptation. We investigated protein expression in five stream stonefly species from four geographic regions along a latitudinal gradient in Japan with varying climatic conditions. The extracted proteins were separated by two‐dimensional gel electrophoresis and identified by matrix‐assisted laser desorption/ionization of time‐of‐flight (MALDI TOF/TOF), yielding 446 proteins. Low interspecies variation in the proteome profiles was observed among five species within geographical regions, presumably due to the co‐occurring species sharing the environments. However, large spatial variations in protein expression were found among four geographic regions, suggesting strong regulation of protein expression in heterogeneous environments, where the spatial variations were positively correlated with water temperature. We identified 21 unique proteins expressed specifically in a geographical region and six common proteins expressed throughout all regions. In warmer regions, metabolic proteins were upregulated, whereas proteins related to cold stress, the photoperiod, and mating were downregulated. Oxygen‐related and energy‐production proteins were upregulated in colder regions with higher altitudes. Thus, our proteomic approach is useful for identifying and understanding important biological functions related to local adaptations by populations of stoneflies.
    September 19, 2017   doi: 10.1002/arch.21422   open full text
  • The light cycle controls the hatching rhythm in Bombyx mori via negative feedback loop of the circadian oscillator.
    Hui Tao, Xue Li, Jian‐Feng Qiu, Heng‐Jiang Liu, Da‐Yan Zhang, Feng Chu, Yanghu Sima, Shi‐Qing Xu.
    Archives of Insect Biochemistry and Physiology. September 05, 2017
    Hatching behavior is a key target in silkworm (Bombyx mori) rearing, especially for the control of Lepidoptera pests. According to previous research, hatching rhythms appear to be controlled by a clock mechanism that restricts or “gates” hatching to a particular time. However, the underlying mechanism remains elusive. Under 12‐h light:12‐h dark photoperiod (LD) conditions, the transcriptional levels of the chitinase5 (Cht5) and hatching enzyme‐like (Hel) genes, as well as the enzymatic activities of their gene products, oscillated in time with ambient light cycles, as did the transcriptional levels of the cryptochrome 1, cryptochrome 2, period (per), and timeless genes, which are key components of the negative feedback loop of the circadian rhythm. These changes were related to the expression profile of the ecdysteroid receptor gene and the hatching behavior of B. mori eggs. However, under continuous light or dark conditions, the hatching behavior, the expression levels of Cht5 and Hel, as well as the enzymatic activities of their gene products, were not synchronized unlike under LD conditions. In addition, immunohistochemistry experiments showed that light promoted the translocation of PER from the cytoplasm to the nucleus. In conclusion, LD cycles regulate the hatching rhythm of B. mori via negative feedback loop of the circadian oscillator.
    September 05, 2017   doi: 10.1002/arch.21408   open full text
  • Heat stress hardening of oriental armyworms is induced by a transient elevation of reactive oxygen species during sublethal stress.
    Takashi Matsumura, Hitoshi Matsumoto, Yoichi Hayakawa.
    Archives of Insect Biochemistry and Physiology. September 05, 2017
    Pre‐exposure to mild heat stress enhances the thermotolerance of insects. Stress hardening is a beneficial physiological plasticity, but the mechanism underlying it remains elusive. Here we report that reactive oxygen species (ROS) concentrations were quickly and transiently elevated in the armyworms, Mythimna separata, by exposing them to 40°C, but not other tested temperatures. Larvae exposed to 40°C had subsequently elevated antioxidant activity and the highest survival of all tested heating conditions. The elevation of ROS after lethal heating at 44°C for 1 h was approximately twofold compared to heating at 40°C. Injection of an optimal amount of hydrogen peroxide (H2O2) similarly caused sequential elevation of ROS and antioxidant activity in the test larval hemolymph, which led to significantly enhanced survival after lethal heat stress. The H2O2‐induced thermotolerance was abolished by coinjection of potent antioxidants such as ascorbic acid or N‐acetylcysteine. Both preheating at 40°C and H2O2 injection enhanced expression of genes encoding superoxide dismutase 1, catalase, and heat shock protein 70 in the fat body of test larvae, indicating the adequate heat stress induced a transient elevation of ROS, followed by upregulation of antioxidant activity. We infer that thermal stress hardening is induced by a small timely ROS elevation that triggers a reduction–oxidation signaling mechanism.
    September 05, 2017   doi: 10.1002/arch.21421   open full text
  • The impact of pollen consumption on honey bee (Apis mellifera) digestive physiology and carbohydrate metabolism.
    Vincent A. Ricigliano, William Fitz, Duan C. Copeland, Brendon M. Mott, Patrick Maes, Amy S. Floyd, Arnold Dockstader, Kirk E. Anderson.
    Archives of Insect Biochemistry and Physiology. August 20, 2017
    Carbohydrate‐active enzymes play an important role in the honey bee (Apis mellifera) due to its dietary specialization on plant‐based nutrition. Secretory glycoside hydrolases (GHs) produced in worker head glands aid in the processing of floral nectar into honey and are expressed in accordance with age‐based division of labor. Pollen utilization by the honey bee has been investigated in considerable detail, but little is known about the metabolic fate of indigestible carbohydrates and glycosides in pollen biomass. Here, we demonstrate that pollen consumption stimulates the hydrolysis of sugars that are toxic to the bee (xylose, arabinose, mannose). GHs produced in the head accumulate in the midgut and persist in the hindgut that harbors a core microbial community composed of approximately 108 bacterial cells. Pollen consumption significantly impacted total and specific bacterial abundance in the digestive tract. Bacterial isolates representing major fermentative gut phylotypes exhibited primarily membrane‐bound GH activities that may function in tandem with soluble host enzymes retained in the hindgut. Additionally, we found that plant‐originating β‐galactosidase activity in pollen may be sufficient, in some cases, for probable physiological activity in the gut. These findings emphasize the potential relative contributions of host, bacteria, and pollen enzyme activities to carbohydrate breakdown, which may be tied to gut microbiome dynamics and associated host nutrition.
    August 20, 2017   doi: 10.1002/arch.21406   open full text
  • Purification and characterization of trypsin produced by gut bacteria from Anticarsia gemmatalis.
    Franciny Martins Pilon, Camila da Rocha Silva, Liliane Evangelista Visôtto, Rafael de Almeida Barros, Neilier Rodrigues da Silva Júnior, Wellington Garcia Campos, Maria Goreti Almeida Oliveira.
    Archives of Insect Biochemistry and Physiology. August 01, 2017
    Purification of active trypsin in the digestive process of insects is essential for the development of potent protease inhibitors (PIs) as an emerging pest control technology and research into insect adaptations to dietary PIs. An important aspect is the presence of proteolytic microorganisms, which contribute to host nutrition. Here, we purified trypsins produced by bacteria Bacillus cereus, Enterococcus mundtii, Enterococcus gallinarum, and Staphylococcus xylosus isolated from the midgut of Anticarsia gemmatalis. The trypsins had a molecular mass of approximately 25 kDa. The enzymes showed increased activity at 40°C, and they were active at pH values 7.5–10. Aprotinin, bis‐benzamidine, and soybean Kunitz inhibitor (SKTI) significantly inhibited trypsin activity. The l‐1‐tosyl‐amido‐2‐phenylethylchloromethyl ketone (TPCK), pepstatin A, E‐64, ethylenediamine tetraacetic acid, and calcium ions did not affect the enzyme activity at the concentrations tested. We infer the purified trypsins do not require calcium ions, by which they differ from the trypsins of other microorganisms and the soluble and insoluble trypsins characterized from A. gemmatalis. These data suggest the existence of different isoforms of trypsin in the velvetbean caterpillar midguts.
    August 01, 2017   doi: 10.1002/arch.21407   open full text
  • Induction of stress‐ and immune‐associated genes in the Indian meal moth Plodia interpunctella against envenomation by the ectoparasitoid Bracon hebetor.
    Tahir Shafeeq, Zain UlAbdin, Kyeong‐Yeoll Lee.
    Archives of Insect Biochemistry and Physiology. July 21, 2017
    Envenomation is an important process in parasitism by parasitic wasps; it suppresses the immune and development of host insects. However, the molecular mechanisms of host responses to envenomation are not yet clear. This study aimed to determine the transcription‐level responses of the Indian meal moth Plodia interpunctella against envenomation of the ectoparasitoid Bracon hebetor. Quantitative real‐time reverse‐transcription PCR was used to determine the transcriptional changes of 13 selected genes, which are associated with development, metabolism, stress, or immunity, in the feeding and wandering fifth instar larvae over a 4‐day period after envenomation. The effects of envenomation on the feeding‐stage larvae were compared with those of starvation in the transcriptional levels of the 13 genes. Most selected genes were altered in their expression by either envenomation or starvation. In particular, a heat shock protein, hsp70, was highly upregulated in envenomated larvae in both the feeding and wandering stages as well as in starved larvae. Further, some genes were upregulated by envenomation in a stage‐specific manner. For example, hsp25 was upregulated after envenomation in the feeding larvae, but hsp90 and an immune‐associated gene, hemolin, were upregulated in the wandering larvae. However, both envenomation and starvation resulted in the downregulation of genes associated with development and metabolism. Taken together, P. interpunctella upregulated stress‐ and immune‐responsive genes, but downregulated genes associated with development and metabolism after envenomation. This study provides important information for understanding the molecular mechanisms of host responses to parasitism.
    July 21, 2017   doi: 10.1002/arch.21405   open full text
  • Localization and functional analysis of the insect‐specific RabX4 in the brain of Bombyx mori.
    Tomohide Uno, Masayuki Furutani, Katsuhiko Sakamoto, Yuichi Uno, Kengo Kanamaru, Akira Mizoguchi, Susumu Hiragaki, Makio Takeda.
    Archives of Insect Biochemistry and Physiology. July 14, 2017
    Rab proteins are small monomeric GTPases/GTP‐binding proteins, which form the largest branch of the Ras superfamily. The different Rab GTPases are localized to the cytosolic face of specific intracellular membranes, where they function as regulators of distinct steps in membrane trafficking. RabX4 is an insect‐specific Rab protein that has no close homolog in vertebrates. There is little information about insect‐specific Rab proteins. RabX4 was expressed in Escherichia coli and subsequently purified. Antibodies against Bombyx mori RabX4 were produced in rabbits for western immunoblotting and immunohistochemistry. Western blotting of neural tissues revealed a single band, at approximately 26 kD. RabX4‐like immunohistochemical reactivity was restricted to neurons of the pars intercerebralis and dorsolateral protocerebrum in the brain. Further immunohistochemical analysis revealed that RabX4 colocalized with Rab6 and bombyxin in the corpus allatum, a neuronal organ that secretes neuropeptides synthesized in the brain into the hemolymph. RabX4 expression in the frontal ganglion, part of the insect stomatogastric nervous system that is found in most insect orders, was restricted to two neurons on the outer region and did not colocalize with allatotropin or Rab6. Furthermore, RNA interference of RabX4 decreased bombyxin expression levels in the brain. These findings suggest that RabX4 is involved in the neurosecretion of a secretory organ in Bombyx mori.
    July 14, 2017   doi: 10.1002/arch.21404   open full text
  • In vitro evidence for the participation of Drosophila melanogaster sperm β‐N‐acetylglucosaminidases in the interactions with glycans carrying terminal N‐acetylglucosamine residues on the egg's envelopes.
    Jari Intra, Concetta Veltri, Daniela Caro, Maria Elisa Perotti, Maria Enrica Pasini.
    Archives of Insect Biochemistry and Physiology. July 10, 2017
    Fertilization is a complex and multiphasic process, consisting of several steps, where egg‐coating envelope's glycoproteins and sperm surface receptors play a critical role. Sperm‐associated β‐N‐acetylglucosaminidases, also known as hexosaminidases, have been identified in a variety of organisms. Previously, two isoforms of hexosaminidases, named here DmHEXA and DmHEXB, were found as intrinsic proteins in the sperm plasma membrane of Drosophila melanogaster. In the present work, we carried out different approaches using solid‐phase assays in order to analyze the oligosaccharide recognition ability of D. melanogaster sperm hexosaminidases to interact with well‐defined carbohydrate chains that might functionally mimic egg glycoconjugates. Our results showed that Drosophila hexosaminidases prefer glycans carrying terminal β‐N‐acetylglucosamine, but not core β‐N‐acetylglucosamine residues. The capacity of sperm β‐N‐acetylhexosaminidases to bind micropylar chorion and vitelline envelope was examined in vitro assays. Binding was completely blocked when β‐N‐acetylhexosaminidases were preincubated with the glycoproteins ovalbumin and transferrin, and the monosaccharide β‐N‐acetylglucosamine. Overall, these data support the hypothesis of the potential role of these glycosidases in sperm–egg interactions in Drosophila.
    July 10, 2017   doi: 10.1002/arch.21403   open full text
  • Prolidase is a critical enzyme for complete gliadin digestion in Tenebrio molitor larvae.
    Valeriia F. Tereshchenkova, Irina A. Goptar, Dmitry P. Zhuzhikov, Mikhail A. Belozersky, Yakov E. Dunaevsky, Brenda Oppert, Irina Yu. Filippova, Elena N. Elpidina.
    Archives of Insect Biochemistry and Physiology. June 29, 2017
    Prolidase is a proline‐specific metallopeptidase that cleaves imidodipeptides with C‐terminal Pro residue. Prolidase was purified and characterized from the Tenebrio molitor larval midgut. The enzyme was localized in the soluble fraction of posterior midgut tissues, corresponding to a predicted cytoplasmic localization of prolidase according to the structure of the mRNA transcript. Expression of genes encoding prolidase and the major digestive proline‐specific peptidase (PSP)—dipeptidyl peptidase 4—were similar. The pH optimum of T. molitor prolidase was 7.5, and the enzyme was inhibited by Z‐Pro, indicating that it belongs to type I prolidases. In mammals, prolidase is particularly important in the catabolism of a proline‐rich protein—collagen. We propose that T. molitor larval prolidase is a critical enzyme for the final stages of digestion of dietary proline‐rich gliadins, providing hydrolysis of imidodipeptides in the cytoplasm of midgut epithelial cells. We propose that the products of hydrolysis are absorbed from the luminal contents by peptide transporters, which we have annotated in the T. molitor larval gut transcriptome. The origin of prolidase substrates in the insect midgut is discussed in the context of overall success of grain feeding insects.
    June 29, 2017   doi: 10.1002/arch.21395   open full text
  • Inga laurina trypsin inhibitor (ILTI) obstructs Spodoptera frugiperda trypsins expressed during adaptive mechanisms against plant protease inhibitors.
    Suzy Wider Machado, Caio Fernando Ramalho Oliveira, Neide Graciano Zério, José Roberto Postali Parra, Maria Lígia Rodrigues Macedo.
    Archives of Insect Biochemistry and Physiology. June 29, 2017
    Plant protease inhibitors (PIs) are elements of a common plant defense mechanism induced in response to herbivores. The fall armyworm, Spodoptera frugiperda, a highly polyphagous lepidopteran pest, responds to various PIs in its diet by expressing genes encoding trypsins. This raises the question of whether the PI‐induced trypsins are also inhibited by other PIs, which we posed as the hypothesis that Inga laurina trypsin inhibitor (ILTI) inhibits PI‐induced trypsins in S. frugiperda. In the process of testing our hypothesis, we compared its properties with those of selected PIs, soybean Kunitz trypsin inhibitor (SKTI), Inga vera trypsin inhibitor (IVTI), Adenanthera pavonina trypsin inhibitor (ApTI), and Entada acaciifolia trypsin inhibitor (EATI). We report that ILTI is more effective in inhibiting the induced S. frugiperda trypsins than SKTI and the other PIs, which supports our hypothesis. ILTI may be more appropriate than SKTI for studies regarding adaptive mechanisms to dietary PIs.
    June 29, 2017   doi: 10.1002/arch.21393   open full text
  • The entomopathogenic fungus Nomuraea rileyi impairs cellular immunity of its host Helicoverpa armigera.
    Ke Zhong, Zhan‐Chi Liu, Jia‐Lin Wang, Xu‐Sheng Liu.
    Archives of Insect Biochemistry and Physiology. June 23, 2017
    In this study, we investigated the effect of the entomopathogenic fungus Nomuraea rileyi on Helicoverpa armigera cellular immune responses. Nomuraea rileyi infection had no effect on total hemocyte count (THC), but impaired hemocyte‐mediated phagocytosis, nodulation, and encapsulation responses. Nomuraea rileyi infection led to a significant reduction in hemocyte spreading. An in vitro assay revealed that plasma from N. rileyi infected H. armigera larvae suppressed the spreading ability of hemocytes from naïve larvae. We infer that N. rileyi suppresses the cellular immune response of its host, possibly by secreting exogenous, cytotoxic compounds into the host's hemolymph.
    June 23, 2017   doi: 10.1002/arch.21402   open full text
  • Knockdown of TOR causing ovarian diapause in a genetically stable brachypterous strain of Nilaparvata lugens.
    Fangzhou Liu, Kaiyin Li, Wanlun Cai, Jing Zhao, Yulan Zou, Hongxia Hua.
    Archives of Insect Biochemistry and Physiology. June 20, 2017
    Brown planthopper (BPH), Nilaparvata lugens (Stål) (Hemiptera: Delphacidae), is one of the most damaging pests of rice crops. BPH is a migratory insect with a delayed ovarian development in migrants classified as reproductive diapause. The molecular mechanism of reproductive diapause remains unclear, although we suspect it might be regulated by one or more nutrient signaling pathways. The target of rapamycin (TOR) pathway regulates cell growth in response to nutritional information, which raised a hypothesis that TOR mediates BPH reproductive diapause. We used a pure brachypterous strain (BS) and a predominantly macropterous strain (MS) to investigate the roles of NlTOR in BPH reproductive diapause. We found that NlTOR is expressed from the nymphal to adult stages, with a higher expression level of NlTOR in BS adults at 1, 2, and 4 days posteclosion than in MS at the same time points. Injection of dsNlTOR into BS nymphs resulted in the termination of BPH female ovary development and the retardation of nymph development. We infer that TOR signaling functions in BPH reproductive diapause by regulating the expression of NlFoxA and NlVitellogenin.
    June 20, 2017   doi: 10.1002/arch.21400   open full text
  • Dietary TiO2 particles modulate expression of hormone‐related genes in Bombyx mori.
    Guofang Shi, Pengfei Zhan, Weiming Jin, JianMing Fei, Lihua Zhao.
    Archives of Insect Biochemistry and Physiology. June 20, 2017
    Silkworm (Bombyx mori) is an economically beneficial insect. Its growth and development are regulated by endogenous hormones. In the present study, we found that feeding titanium dioxide nanoparticles (TiO2NP) caused a significant increase of body size. TiO2NP stimulated the transcription of several genes, including the insulin‐related hormone bombyxin, PI3K/Akt/TOR (where PI3K is phosphatidylinositol 3‐kinase and TOR is target of rapamycin), and the adenosine 5′‐monophosphateactivated protein kinase (AMPK)/target of rapamycin (TOR) pathways. Differentially expressed gene (DEG) analysis documented 26 developmental hormone signaling related genes that were differentially expressed following dietary TiO2NP treatment. qPCR analysis confirmed the upregulation of insulin/ecdysteroid signaling genes, such as bombyxin B‐1, bombyxin B‐4, bombyxin B‐7, MAPK, P70S6K, PI3k, eIF4E, E75, ecdysteroid receptor (EcR), and insulin‐related peptide binding protein precursor 2 (IBP2). We infer from the upregulated expression of bombyxins and the signaling network that they act in bombyxin‐stimulated ecdysteroidogenesis.
    June 20, 2017   doi: 10.1002/arch.21397   open full text
  • Evaluation of flubendiamide‐induced mitochondrial dysfunction and metabolic changes in Helicoverpa armigera (Hubner).
    Bharat Nareshkumar, Shaik Mohammad Akbar, Hari Chand Sharma, Senigala K. Jayalakshmi, Kuruba Sreeramulu.
    Archives of Insect Biochemistry and Physiology. June 20, 2017
    Phthalic acid diamide insecticides are the most effective insecticides used against most of the lepidopteran pests including Helicoverpa armigera, a polyphagous pest posing threat to several crops worldwide. The present studies were undertaken to understand different target sites and their interaction with insect ryanodine receptors (RyR). Bioassays indicated that flubendiamide inhibited the larval growth in dose‐dependent manner with LD50 value of 0.72 μM, and at 0.8 μM larval growth decreased by about 88%. Flubendiamide accelerated the Ca2+‐ATPase activity in dose‐dependent trend, and at 0.8 μM, the activity was increased by 77.47%. Flubendiamide impedes mitochondrial function by interfering with complex I and F0F1‐ATPase activity, and at 0.8 μM the inhibition was found to be about 92% and 50%, respectively. In vitro incubation of larval mitochondria with flubendiamide induced the efflux of cytochrome c, indicating the mitochondrial toxicity of the insecticide. Flubendiamide inhibited lactate dehydrogenase and the accumulation of H2O2, thereby preventing the cells from lipid peroxidation compared to control larvae. At 0.8 μM the LDH, H2O2 content and lipid peroxidation was inhibited by 98.44, 70.81, and 70.81%, respectively. Cytochrome P450, general esterases, AChE, and antioxidant enzymes (catalase and superoxide dismutase) exhibited a dose‐dependent increasing trend, whereas alkaline phosphatase and the midgut proteases, except amino peptidase, exhibited dose‐dependent inhibition in insecticide‐fed larvae. The results suggest that flubendiamide induced the harmful effects on the growth and development of H. armigera larvae by inducing mitochondrial dysfunction and inhibition of midgut proteases, along with its interaction with RyR.
    June 20, 2017   doi: 10.1002/arch.21401   open full text
  • Feeding regulation by neuropeptide Y on Asian corn borer Ostrinia furnacalis.
    Zhen Yue, Zhangwu Zhao.
    Archives of Insect Biochemistry and Physiology. May 30, 2017
    The Asian Corn Borer Ostrinia furnacalis is a major agricultural pest. In this study, a full‐length neuropeptide Y (npy) gene in O. furnacalis was sequenced and cloned from cDNA library, which contains an ORF of 273 bp by encoding 90 amino acid residues. The mature OfurNPY is composed of 29 amino acids with amidation in C‐terminal. The spatiotemporal expression analysis showed that npy highest expression level was in the midgut of the fifth instar larvae (the gluttony period). When the expression of npy was knocked down by feeding or injecting dsNPY, larval food consumption, body size, and body weight were significantly inhibited compared to controls. These results indicate that NPY is an important regulator in the control of feeding of O. furnacalis.
    May 30, 2017   doi: 10.1002/arch.21396   open full text
  • Identification of β‐chain of FoF1‐ATPase in apoptotic cell population induced by Microplitis bicoloratus bracovirus and its role in the development of Spodoptera litura.
    Tian‐Chao Kou, Yue‐Tong Liu, Ming Li, Yang Yang, Wei Zhang, Ji‐Hui Cui, Xue‐Wen Zhang, Shu‐Mei Dong, Sha Xu, Shan You, Dong‐Shuai Yu, Zun‐Yu Pang, Kai‐Jun Luo.
    Archives of Insect Biochemistry and Physiology. May 30, 2017
    Two physiological changes of Spodoptera litura parasitized by Microplitis bicoloratus are hemocyte‐apoptosis and retarded immature development. β‐Chain of FoF1‐ATPase was found from a S. litura transcriptome. It belongs to a conserved P‐loop NTPase superfamily, descending from a common ancestor of Lepidopteran clade. However, the characterization of β‐chain of ATPase in apoptotic cells and its involvement in development remain unknown. Here, the ectopic expression and endogenous FoF1‐ATPase β‐chain occurred on S. litura cell membrane: in vivo, at the late stage of apoptotic hemocyte, endogenous FoF1‐ATPase β‐chain was stably expressed during M. bicoloratus larva development from 4 to 7 days post‐parasitization; in vitro, at an early stage of pre‐apoptotic Spli221 cells by infecting with M. bicoloratus bracovirus particles, the proteins were speedily recover expression. Furthermore, endogenous FoF1‐ATPase β‐chain was localized on the apoptotic cell membrane. RNA interference (RNAi) of FoF1‐ATPase β‐chain led to significantly decreased head capsule width. This suggested that FoF1‐ATPase β‐chain positively regulated the development of S. litura. The RNAi effect on the head capsule width was enhanced with parasitism. Our research found that FoF1‐ATPase β‐chain was expressed and localized on the cell membrane in the apoptotic cells, and involved in the development of S. litura.
    May 30, 2017   doi: 10.1002/arch.21389   open full text
  • Purification and functional characterization of lectin with phenoloxidase activity from the hemolymph of cockroach, Periplaneta americana.
    Ganesh Arumugam, Bhuvaragavan Sreeramulu, Ramaraj Paulchamy, Sakthivel Thangavel, Janarthanan Sundaram.
    Archives of Insect Biochemistry and Physiology. May 30, 2017
    Lectins also identified as hemagglutinins are multivalent proteins and on account of their fine sugar‐binding specificity play an important role in immune system of invertebrates. The present study was carried out on the hemolymph lectin of cockroach, Periplaneta americana with appropriate screening and purification to understand its molecular as well as functional nature. The lectin from the hemolymph was purified using ion‐exchange chromatography. The approximate molecular weight of purified lectin was 340 kDa as determined by FPLC analysis. Rabbit erythrocytes were highly agglutinated with purified lectin from the hemolymph of P. americana. The hemagglutination activity (HA) of lectin was specifically inhibited by fucose. Glycoproteins also inhibited the HA activity of lectin. The amino acid sequences of the purified lectin revealed homology with amino acid sequences of allergen proteins from P. americana. Purified lectin showed the highest phenoloxidase activity against dopamine. The activators such as exogenous proteases and LPS from Escherichia coli and Salmonella minnesota significantly enhanced the PO activity of the purified lectin. Besides, the presence of copper and hemocyanin conserved domain in the purified lectin provided a new facet that insects belonging to the ancient clade such as cockroaches retained some traces of evolutionary resemblance in possessing lectin of ancient origin.
    May 30, 2017   doi: 10.1002/arch.21390   open full text
  • Comparative transcriptomic analysis of Bombyx mori fat body tissue following dietary restriction.
    Ye Pan, Peng Lü, Qinyun Wang, Feifei Zhu, Chengjun Li, Yuanqing He, Keping Chen.
    Archives of Insect Biochemistry and Physiology. April 27, 2017
    Dietary restriction (DR) refers to a reduction in food intake to induce undernutrition but not malnutrition, which extends the lifespan of multiple species. Although there are invertebrate aging models, such as the Caenorhabditis elegans and Drosophila melanogaster, aging studies in Lepidoptera are few in number and the underlying life‐extending molecular mechanisms are not clear. Research on a broader range of animals is necessary to support generalizations on mechanisms of aging and rates of aging. The aim of this study was to further investigate genes and pathways associated with DR in Bombyx mori. Here, we used mRNA deep sequencing (RNA‐seq) to further investigate genes and pathways associated with DR. The transcriptome profiles showed that most of the differentially expressed genes were upregulated following DR, and genes involved in amino acid and protein metabolism, RNA metabolism and translation, energy metabolism, nitrogen metabolism, and juvenile hormone pathway‐related proteins were particularly affected. DR also affects the metabolism of uric acid and urea, which accumulated in silkworm following DR. We speculate that this may not be due to activation of uric acid biosynthesis, but rather by downregulating the degradation of uric acid and urea. These results may help us to understand the mechanisms by which DR prolong lifespan in insects and other animals.
    April 27, 2017   doi: 10.1002/arch.21388   open full text
  • Feeding‐induced phenol production in Capsicum annuum L. influences Spodoptera litura F. larval growth and physiology.
    Vijaya Movva, Usha Rani Pathipati.
    Archives of Insect Biochemistry and Physiology. April 27, 2017
    We studied the role of induced plant phenols as a defense response to insect herbivory. Phenolic compounds were induced in Capsicum annuum L., the source of many culinary peppers, after feeding by different stages of the insect pest, Spodoptera litura F. The phenols were identified and quantified using high performance liquid chromatography (HPLC) and effects produced by these phenols on larval development were studied. Vanillic acid was identified in plants challenged by second, fourth, and fifth instar larvae, but not in plants challenged by third instar nor unchallenged plants. Syringic acid production was induced in chili plants infested with second (0.429 ± 0.003 μg/g fresh weight, fourth (0.396 ± 0.01 μg/g fresh weight), and fifth instar (5.5 ± 0.06 μg/g fresh weight) larvae, compared to untreated plants (0.303 ± 0.01 μg/g fresh weight) plants. Leaves surface treated with the rutin deterred oviposition. Dietary exposure to chlorogenic acid, vanillic acid, syringic acid, sinapic acid, and rutin led to enhanced activities of detoxifying enzymes, β‐glucosidase, carboxyl esterase, glutathione S‐transferase, and glutathione reductase in the midgut tissues of all the larval instars, indicating the toxic nature of these compounds. Protein carbonyl content and acetylcholinesterase activity was analyzed to appreciate the role of induced plant phenols in insect protein oxidation and terminating nerve impulses.
    April 27, 2017   doi: 10.1002/arch.21387   open full text
  • Identification of a hypertrehalosemic factor in Spodoptera exigua.
    Youngjin Park, Yonggyun Kim.
    Archives of Insect Biochemistry and Physiology. April 25, 2017
    Trehalose is a major blood sugar in insects with a range of physiological functions, including an energy source and a cryoprotectant. Hemolymph trehalose concentrations are tightly regulated according to physiological conditions. An insulin‐like peptide, SeILP1, downregulates hemolymph trehalose concentrations in Spodoptera exigua. Here, we identified a factor that upregulates hemolymph trehalose concentration in S. exigua. Hemolymph trehalose concentrations were significantly increased after immune challenge or under starvation in a time‐dependent manner. To determine endocrine factors responsible for the upregulation, stress‐associated mediators, such as octopamine, serotonin, or eicosanoids were injected, but they did not upregulate hemolymph trehalose. On the other hand, injection with Schistocerca gregaria adipokinetic hormone (AKH) significantly increased hemolymph trehalose concentration in S. exigua. During upregulation of hemolymph trehalose by AKH injection, trehalose degradation appeared to be inhibited because expression of trehalase and SeILP1 were significantly suppressed while that of trehalose phosphate synthase was not significantly changed. Interrogation of a Spodoptera genome database identified an S. exigua AKH‐like gene and its expression was confirmed. During starvation, its expression concentrations were increased, although RNA interference specific to the AKH‐like hypertrehalosemic factor (SeHTF) gene significantly prevented the upregulation of hemolymph trehalose concentrations during starvation. A synthetic peptide of SeHTF was prepared and injected into S. exigua larvae. At nanomolar concentration, the synthetic SeHTF peptide effectively upregulated hemolymph trehalose concentrations. Here we report a novel hypertrehalosemic factor in S. exigua (SeHTF).
    April 25, 2017   doi: 10.1002/arch.21386   open full text
  • Functional analysis of two polygalacturonase genes in Apolygus lucorum associated with eliciting plant injury using RNA interference.
    Wanna Zhang, Bing Liu, Yanhui Lu, Gemei Liang.
    Archives of Insect Biochemistry and Physiology. March 30, 2017
    Salivary enzymes of many piercing–sucking insects lead to host plant injury. The salivary enzymes, polygalacturonase (PGs), act in insect feeding. PG family genes have been cloned from the mirid bug Apolygus lucorum, a pest of cotton and other host crops in China. We investigated the function of two PG genes that are highly expressed in A. lucorum nymphs (PG3‐4) and adults (PG3‐5), using siRNA injection‐based RNA interference (RNAi). Accumulation of mRNA encoding both genes and their cognate proteins was significantly reduced (>60%) in experimental compared control green fluorescent protein (GFP) siRNA‐treated mirids at 48 h post injection. Injury levels of cotton buds were also significantly reduced after injecting saliva isolated from PG3‐4 and PG3‐5 siRNA‐treated A. lucorum. These results demonstrate that these two PG act in A. lucorum elicitation of plant injury.
    March 30, 2017   doi: 10.1002/arch.21382   open full text
  • Characterization of two novel antimicrobial peptides from the cuticular extracts of the ant Trichomyrmex criniceps (Mayr), (Hymenoptera: Formicidae).
    Nagachaitanya Bhagavathula, Venkateshwarlu Meedidoddi, Simon Bourque, Reshmy Vimaladevi, Santoshkumar Kesavakurup, Dayanandan Selvadurai, Sameer Shrivastava, Chandrashekara Krishnappa.
    Archives of Insect Biochemistry and Physiology. March 27, 2017
    Antimicrobial peptides (AMPs) from cuticular extracts of worker ants of Trichomyrmex criniceps (Mayr, Hymenoptera: Formicidae) were isolated and evaluated for their antimicrobial activity. Eight peptides ranging in mass from 804.42 to 1541.04 Da were characterized using a combination of analytical and bioinformatics approach. All the eight peptides were novel with no similarity to any of the AMPs archived in the Antimicrobial Peptide Database. Two of the eight novel peptides, the smallest and the largest by mass were named Crinicepsin‐1 and Crinicepsin‐2 and were chemically synthesized by solid phase peptide synthesis. The two synthetic peptides had antibacterial and weak hemolytic activity.
    March 27, 2017   doi: 10.1002/arch.21381   open full text
  • Characterization of candidate odorant‐binding proteins and chemosensory proteins in the tea geometrid Ectropis obliqua Prout (Lepidoptera: Geometridae).
    Liang Sun, Teng‐Fei Mao, Yu‐Xing Zhang, Jian‐Jian Wu, Jia‐He Bai, Ya‐Nan Zhang, Xing‐Chuan Jiang, Kun‐Shan Yin, Yu‐Yuan Guo, Yong‐Jun Zhang, Qiang Xiao.
    Archives of Insect Biochemistry and Physiology. March 21, 2017
    Insects rely heavily on their sophisticated chemosensory systems to locate host plants and find conspecific mates. Although the molecular mechanisms of odorant recognition in many Lepidoptera species have been well explored, limited information has been reported on the geometrid moth Ectropis obliqua Prout, an economically important pest of tea plants. In the current study, we first attempted to identify and characterize the putative olfactory carrier proteins, including odorant‐binding proteins (OBPs) and chemosensory proteins (CSPs). By analyzing previously obtained transcriptomic data of third‐instar larvae, five OBPs and 14 CSPs in E. obliqua were identified. Sequence alignment, conserved motif identification, and phylogenetic analysis suggested that candidate proteins have typical characteristics of the insect OBP or CSP family. The expression patterns regarding life stages and different tissues were determined by quantitative real‐time PCR. The results revealed that four transcripts (OBP2, OBP4 and CSP8, CSP10) had larvae preferential expression profiles and nine candidate genes (PBP1, OBP1 and CSP2, CSP4, CSP5, CSP6, CSP7, CSP11, and CSP13) were adult‐biased expressed. Further specific tissue expression profile evaluation showed that OBP1, OBP2, OBP4, and PBP1 were highly expressed at olfactory organs, implying their potential involvement in chemical cue detection, whereas CSPs were ubiquitously detected among all of the tested tissues and could be associated with multiple physiological functions. This study provided a foundation for understanding the physiological functions of OBPs and CSPs in E. obliqua and will help pave the way for the development of a new environmental friendly pest management strategy against the tea geometrid moth.
    March 21, 2017   doi: 10.1002/arch.21383   open full text
  • Chemicals isolated from Justicia adhatoda Linn reduce fitness of the mosquito, Aedes aegypti L.
    Annamalai Thanigaivel, Sengottayan Senthil‐Nathan, Prabhakaran Vasantha‐Srinivasan, Edward‐Sam Edwin, Athirstam Ponsankar, Selvaraj Selin‐Rani, Venkatraman Pradeepa, Muthiah Chellappandian, Kandaswamy Kalaivani, Ahmed Abdel‐Megeed, Raman Narayanan, Kadarkarai Murugan.
    Archives of Insect Biochemistry and Physiology. March 07, 2017
    Extracts from Justicia adhatoda L. (Acanthaceae) strongly reduced the fitness of the mosquito, Aedes aegypti Linn. The methanolic extracts inhibited several enzymes responsible for protecting insects from oxidative and other damage, including glutathione‐S‐transferase, superoxide dismutase, cytochrome P450, and α‐ and β‐esterases. They increased repellency (maximum repellency at 100 ppm) in host‐seeking adult females using the “arm‐in cage assay.” Histopathological examination showed the extracts led to serious midgut cell damage. Justicia adhatoda extracts led to reduced fecundity and oviposition of gravid females compared to controls. The extracts led to substantially reduced A. aegypti survival. We infer that the extracts have potential to reduce pathogen transmission by suppressing population growth of A. aegypti, and possibly other mosquito species.
    March 07, 2017   doi: 10.1002/arch.21384   open full text
  • Knockdown of a putative argininosuccinate lyase gene reduces arginine content and impairs nymphal development in Nilaparvata lugens.
    San‐Yue Yuan, Guo‐Qing Li, Pin‐Jun Wan, Qiang Fu, Feng‐Xiang Lai, Li‐Li Mu.
    Archives of Insect Biochemistry and Physiology. March 02, 2017
    Nilaparvata lugens is a typical phloem feeder. Rice phloem is high in simple sugars and very low in essential amino acids. Nilaparvata lugens harbors an ascomycete Entomomyces delphacidicola that hypothetically biosynthesizes several amino acids to meet the nutrition requirement of the planthopper. Among these amino acids, here, we focused on arginine biosynthesis. A complete cDNA of an E. delphacidicola gene, arginine‐succinate lyase, EdArg4, the last step in arginine biosynthesis, was obtained. RNAi‐mediated suppression of EdArg4 reduced arginine content in the hemolymph, and decreased the expression of several arginine biosynthesis genes. Silencing of EdArg4 delayed nymphal development and led to nymphal lethality. About 20% of the EdArg4 RNAi surviving adults were deformed. The most obvious defect was wider and larger abdomen. The EdArg4 RNAi‐treated planthoppers had thickened wings and enlarged antennae, legs, and anal tubes and a few adults did not normally emerge. Arginine deficiency in the EdArg4 RNAi planthoppers repressed nitric oxide signaling, determined at the transcriptional level. We infer that E. delphacidicola biosynthesizes essential arginine to compensate for nutrition deficiency in N. lugens.
    March 02, 2017   doi: 10.1002/arch.21385   open full text
  • The adipokinetic hormone of Mantodea in comparison to other Dictyoptera.
    Gerd Gäde, Heather G. Marco.
    Archives of Insect Biochemistry and Physiology. February 22, 2017
    Six species of the order Mantodea (praying mantises) are investigated for the presence and sequence of putative adipokinetic hormones (AKHs). The selected species span a wide evolutionary range of various families and subfamilies of the clade Mantodea. The corpora cardiaca of the different species are dissected, methanolic extracts prepared, peptides separated by liquid chromatography, and AKHs detected and sequenced by ion trap mass spectrometry. All six species investigated contain an octapeptide with the primary structure pGlu‐Val‐Asn‐Phe‐Thr‐Pro‐Asn‐Trp amide, which is code‐named Emppe‐AKH and had been found earlier in three other species of Mantodea. Conspecific bioassays with the species Creoboter sp. (family Hymenopodidae) reveal an adipokinetic but not a hypertrehalosemic function of Emppe‐AKH. Comparison with other members of the Dictyoptera (cockroaches, termites) show that Emppe‐AKH is only found in certain termites, which have been recently placed into the Blattaria (cockroaches) as sister group to the family Cryptocercidae. Termites and cockroaches both show biodiversity in the sequence of AKHs, and some cockroach species even contain two AKHs. In contrast, all praying mantises—irrespective of their phylogenetic position—synthesize uniformly only one and the same octapeptide Emppe‐AKH.
    February 22, 2017   doi: 10.1002/arch.21376   open full text
  • Localization patterns of dopamine active transporter synthesizing cells during development of brine shrimp.
    Bo Yong Kim, Gyeong Hee Shin, In Soo Lee, Suhng Wook Kim, Ho Seung Kim, Jin Kwan Kim, Seung Gwan Lee.
    Archives of Insect Biochemistry and Physiology. February 16, 2017
    There have been many studies on dopamine active transporter (DAT) in humans and laboratory animals; however, there is a lack of information on DAT in brine shrimp. In this study, we demonstrated the neuronal and nonneuronal characteristics of DAT‐synthesizing (DAT+ cells) during development of brine shrimp. In neuronal cells, the DAT+ neurons in the central body and lobes of a protocerebrum (PC) controlled the deutocerebrum. The sensory cells of nauplius eyes projected their decussated axons to the PC, and the DAT+ cells at the posterior region were associated with migration and control of the 10 posterior neurons during the early nauplius stage. In nonneuronal cells, the five types of glands, that is, the salt, antennal, mandible, and accessory glands and posterior gland1 and gland2 synthesized DAT protein. In addition, the gut and rectum dilator muscles and renal cells expressed DAT protein. Thus, DAT protein acts in the development of several types of cells during development of brine shrimp.
    February 16, 2017   doi: 10.1002/arch.21378   open full text
  • Differential responses of Helicoverpa armigera C‐type immunlectin genes to the endoparasitoid Campoletis chlorideae.
    Xiong‐Ya Wang, Su‐Fen Bai, Xin Li, Shi‐Heng An, Xin‐Ming Yin, Xian‐Chun Li.
    Archives of Insect Biochemistry and Physiology. February 16, 2017
    The C‐type lectins mediate nonself recognition in insects. The previous studies focused on host immunlectin response to bacterial infection; however, the molecular basis of immunlectin reactions to endoparasitoids has not been elucidated. The present study investigated the effect of parasitization by Campoletis chlorideae on hemagglutination activity (HA; defined as the ability of lectin to agglutinate erythrocytes or other cells), and transcriptional expression of C‐type immunlectin genes in the larval host, Helicoverpa armigera. Parasitization induced four‐ to eightfold higher HA in the parasitized larvae, compared to nonparasitized larvae at days 2 and 6 postparasitization (PP), however inhibited HA at other days PP. Eight C‐type lectins were differentially expressed in different host developmental stages, from feeding to wandering stage. The mRNA levels of HaCTL1, HaCTL3, HaCTL4, and HaCTL5 were upregulated and HaCTL2 and HaCTL7 were downregulated. Tissue analysis showed that HaCTLs were mainly expressed in fat body or hemocytes, while HaCTL5 was highly expressed in testes. The effects of parasitization on the lectin expression patterns differed. Lectins except HaCTL6 or HaCTL5 were significantly down‐ or upregulated in parasitized larvae at day 4 or 6 PP compared with that of nonparasitized larvae. We infer from our results that C‐type immunlectins are involved in host–parasitoid interactions, and parasitization alter host immunlectin levels both in inhibiting and promoting host immune defenses to endoparasitoids. These immunlectin genes indicated an altered physiological status of the host insect, depending on developmental stage, tissue, and parasitization.
    February 16, 2017   doi: 10.1002/arch.21379   open full text
  • RNA interference of carboxyesterases causes nymph mortality in the Asian citrus psyllid, Diaphorina citri.
    Abdelaziz Kishk, Helmy A. I. Anber, Tsamoh K. AbdEl‐Raof, AbdEl‐Hakeem D. El‐Sherbeni, Sobhy Hamed, Siddarame Gowda, Nabil Killiny.
    Archives of Insect Biochemistry and Physiology. February 13, 2017
    Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is an important pest of citrus. In addition, D. citri is the vector of Huanglongbing, a destructive disease in citrus, also known as citrus greening disease caused by Candidatus Liberibacter asiaticus. Huanglongbing causes huge losses for citrus industries. Insecticide application for D. citri is the major strategy to prevent disease spread. The heavy use of insecticides causes development of insecticide resistance. We used RNA interference (RNAi) to silence genes implicated in pesticide resistance in order to increase the susceptibility. The activity of dsRNA to reduce the expression of carboxyesterases including esterases FE4 (EstFE4) and acetylcholinesterases (AChe) in D. citri was investigated. The dsRNA was applied topically to the fourth and fifth instars of nymphs. We targeted several EstFE4 and AChe genes using dsRNA against a consensus sequence for each of them. Five concentrations (25, 50, 75, 100, 125 ng/μl) from both dsRNAs were used. The treatments with the dsRNA caused concentration dependent nymph mortality. The highest gene expression levels of both AChe and EstFE4 were found in the fourth and fifth nymphal instars. Gene expression analysis showed that AChe genes were downregulated in emerged adults from dsRNA‐AChe‐treated nymphs compared to controls. However, EstFE4 genes were not affected. In the same manner, treatment with dsRNA‐EstFE4 reduced expression level of EstFE4 genes in emerged adults from treated nymphs, but did not affect the expression of AChe genes. In the era of environmentally friendly control strategies, RNAi is a new promising venue to reduce pesticide applications.
    February 13, 2017   doi: 10.1002/arch.21377   open full text
  • Molecular cloning, expression profile, odorant affinity, and stability of two odorant‐binding proteins in Macrocentrus cingulum Brischke (Hymenoptera: Braconidae).
    Tofael Ahmed, Tiantao Zhang, Zhenying Wang, Kanglai He, Shuxiong Bai.
    Archives of Insect Biochemistry and Physiology. January 30, 2017
    The polyembryonic endoparasitoid wasp Macrocentrus cingulum Brischke (Hymenoptera: Braconidae) is deployed successfully as a biocontrol agent for corn pest insects from the Lepidopteran genus Ostrinia in Europe and throughout Asia, including Japan, Korea, and China. The odorants are recognized, bound, and solubilized by odorant‐binding protein (OBP) in the initial biochemical recognition steps in olfaction that transport them across the sensillum lymph to initiate behavioral response. In the present study, we examine the odorant‐binding effects on thermal stability of McinOBP2, McinOBP3, and their mutant form that lacks the third disulfide bonds. Real‐time PCR experiments indicate that these two are expressed mainly in adult antennae, with expression levels differing by sex. Odorant‐binding affinities of aldehydes, terpenoids, and aliphatic alcohols were measured with circular dichroism spectroscopy based on changes in the thermal stability of the proteins upon their affinities to odorants. The obtained results reveal higher affinity of trans‐caryophelle, farnesene, and cis‐3‐Hexen‐1‐ol exhibits to both wild and mutant McinOBP2 and McinOBP3. Although conformational flexibility of the mutants and shape of binding cavity make differences in odorant affinity between the wild‐type and mutant, it suggested that lacking the third disulfide bond in mutant proteins may have chance to incorrect folded structures that reduced the affinity to these odorants. In addition, CD spectra clearly indicate proteins enriched with α‐helical content.
    January 30, 2017   doi: 10.1002/arch.21374   open full text
  • The dipteran parasitoid Exorista bombycis induces pro‐ and anti‐oxidative reactions in the silkworm Bombyx mori: Enzymatic and genetic analysis.
    Pooja Makwana, Appukuttan Nair R. Pradeep, Shambhavi P. Hungund, Kangayam M. Ponnuvel, Kanika Trivedy.
    Archives of Insect Biochemistry and Physiology. January 17, 2017
    Hymenopteran parasitoids inject various factors including polydnaviruses along with their eggs into their host insects that suppress host immunity reactions to the eggs and larvae. Less is known about the mechanisms evolved in dipteran parasitoids that suppress host immunity. Here we report that the dipteran, Exorista bombycis, parasitization leads to pro‐oxidative reactions and activation of anti‐oxidative enzymes in the silkworm Bombyx mori larva. We recorded increased activity of oxidase, superoxide dismutase, thioredoxin peroxidase, catalase, glutathione‐S‐transferase (GST), and peroxidases in the hemolymph plasma, hemocytes, and fat body collected from B. mori after E. bombycis parasitization. Microarray and qPCR showed differential expression of genes encoding pro‐ and anti‐oxidant enzymes in the hemocytes. The significance of this work lies in increased understanding of dipteran parasitoid biology.
    January 17, 2017   doi: 10.1002/arch.21373   open full text
  • Down‐regulation of a chitin synthase a gene by RNA interference enhances pathogenicity of Beauveria bassiana ANU1 against Spodoptera exigua (HÜBNER).
    Jung‐Bok Lee, Hyun Soo Kim, Youngjin Park.
    Archives of Insect Biochemistry and Physiology. January 17, 2017
    Chitin synthase (CHS) is an important enzymatic component, which is required for chitin formation in the cuticles and cuticular linings of other tissues in insects. CHSs have been divided into two classes, classes A and B, based on their amino acid sequence similarities and functions. Class A CHS (CHS‐A) is specifically expressed in the epidermis and related ectodermal cells such as tracheal cells, while class B CHS (CHS‐B) is expressed in gut epithelial cells that produce peritrophic matrices. In this study, we cloned the CHS‐A gene from the beet armyworm, Spodoptera exigua (SeCHS‐A). The SeCHS‐A contains an open reading frame of 4,698 nucleotides, encoding a protein of 1,565 amino acids with a predicted molecular mass of approximately 177.8 kDa. The SeCHS‐A mRNA was expressed in all developmental stages and specifically in the epidermis and tracheae tissue by quantitative real‐time‐PCR analysis. Expression of SeCHS‐A gene was suppressed by feeding double‐stranded RNA (dsCHS‐A, 400 ng/larva) in the third instar larvae of S. exigua. Suppression of the SeCHS‐A gene expression significantly increased 35% of mortality on pupation of S. exigua. Also, the third instar larvae fed with dsCHS‐A significantly increased susceptibility to entomopathogenic fungi, Beauveria bassiana ANU1 at 3 days after treatment. These results suggest that the SeCHS‐A gene plays an important role in development of S. exigua and RNA interference may apply to effective pest control with B. bassiana.
    January 17, 2017   doi: 10.1002/arch.21371   open full text
  • Characterization of cellulose degrading bacteria from the larval gut of the white grub beetle Lepidiota mansueta (Coleoptera: Scarabaeidae).
    Gautam Handique, Amrita Phukan, Badal Bhattacharyya, Abu Adil Lutful Haque Baruah, Syed Wasifur Rahman, Rajen Baruah.
    Archives of Insect Biochemistry and Physiology. January 17, 2017
    The goal of this study is to identify and characterize the cellulose degrading microorganisms in the larval gut of the white grub beetle, Lepidiota mansueta. Thirty bacterial strains were isolated and tested for cellulolytic activity using soluble carboxymethyl cellulose (CMC) degrading assays. Of these strains, five (FGB1, FB2, MB1, MB2, and HB1) degrade cellulose. Cellulolytic activity was determined based on formation of clear zone and cellulolytic index on CMC plate media. The highest cellulolytic index (2.14) was found in FGB1. Partial 16S rDNA sequencing, morphological, and biochemical tests were used to identify and characterize the five isolates, all Citrobacter sp. (Enterobacteriaceae). This study identifies new cellulose degrading microorganisms from the larval gut of L. mansueta. The significance of identifying these strains lies in possible application in cellulose degradation.
    January 17, 2017   doi: 10.1002/arch.21370   open full text
  • Identification and characterization of microRNAs expressed in antennae of Holotrichia parallela Motschulsky and their possible roles in olfactory regulation.
    Shang Wang, Jian‐Kun Yi, Shuang Yang, Yan Liu, Ju‐Hong Zhang, Jing‐Hui Xi.
    Archives of Insect Biochemistry and Physiology. January 02, 2017
    MicroRNAs (miRNAs) are small noncoding RNAs that play posttranscriptional, regulatory roles in various biological processes. However, there has been limited investigation into the potential function of miRNAs in olfaction. The coleopteran Holotrichia parallela is an economically important pest, and miRNAs have been identified in only one coleopteran (Tribolium castaneum). Therefore, this study was conducted to identify miRNAs expressed in the antennae of H. parallela and obtain insights into their possible roles in olfaction. By combining deep sequencing and miRDeep2 software, a total of 99 miRNAs, including 76 conserved miRNAs and 23 novel miRNAs, were identified from H. parallela antennae. The 76 conserved miRNAs belong to 63 families and the other 23 may be species specific or tissue specific. The identified miRNAs have many conserved features of miRNAs. Evaluation of the conservation of the identified miRNA families across different species revealed that most of the families are insect specific. The prediction and annotation of targets suggested that 13 of the identified miRNAs participate in olfactory regulation. Gender differences in antennal expression of nine of the olfactory‐related miRNAs were confirmed by quantitative real‐time PCR.
    January 02, 2017   doi: 10.1002/arch.21369   open full text
  • Alkaline serine proteases from Helicoverpa armigera: potential candidates for industrial applications.
    Shaik Mohammad Akbar, Hari Chand Sharma.
    Archives of Insect Biochemistry and Physiology. December 26, 2016
    We characterized trypsin‐ and chymotrypsin‐like serine alkaline proteases from cotton bollworm, Helicoverpa armigera, for their probable potential application as additives in various bio‐formulations. Purification was achieved by using hydroxylapatite, DEAE sephadex and CM sephadex columns, which resulted in increased enzyme activity by 13.76‐ and 14.05‐fold for trypsin and chymotrypsin, respectively. Michaelis–Menten constants (Km) for substrates of trypsin and chymotrypsin, BApNA and SAAPFpNA, were found to be 1.25 and 0.085 mM, correspondingly. Fluorescent zymogram analysis indicated the presence of five trypsin bands with molecular masses of ∼21, 25, 38, 40, and 66 kDa and two chymotrypsin bands with molecular masses of ∼29 and 34 kDa in SDS‐PAGE. The optimum pH was 10.0 and optimum temperature was 50°C for proteolytic activity for the purified proteases. The proteases were inhibited by synthetic inhibitors such as PMSF, aprotonin, leupeptin, pefabloc, and antipain. TLCK and TPCK inhibited about 94 and 90% of trypsin and chymotrypsin activity, respectively, while EDTA, EGTA, E64, pepstatin, idoacetamide, and bestatin did not affect the enzymes. The purified enzymes exhibited high stability and compatibility with metal ions; oxidizing, reducing, and bleaching agents; organic solvents; and commercial detergents. Short life cycles, voracious feeding behavior, and production of multiple forms of proteases in the midgut with rapid catalytic activity and chemostability can serve H. armigera as an excellent alternative source of industrially important proteases for use as additives in stain removers, detergents, and other bio‐formulations. Identification of enzymes with essential industrial properties from insect species could be a bioresource.
    December 26, 2016   doi: 10.1002/arch.21367   open full text
  • Characterization and functional study of a Cecropin‐like peptide from the Chinese oak silkworm, Antheraea pernyi.
    Shao‐Liang Fang, Lei Wang, Qi Fang, Chen Chen, Xiao‐San Zhao, Cen Qian, Guo‐Qing Wei, Bao‐Jian Zhu, Chao‐Liang Liu.
    Archives of Insect Biochemistry and Physiology. December 23, 2016
    In present study, a Cecropin‐like peptide from Antheraea pernyi (ApCec) was cloned and characterized. The full‐length ApCec cDNA encoded a protein with 64 amino acids including a putative 22‐amino‐acid signal peptide, a 4‐amino‐acid propeptide, and a 38‐amino‐acid mature peptide. ApCec gene was highly expressed in Malpighian tubules of A. pernyi after induction for 24 h by Escherichia coli in PBS. Pro‐ApCec (including propeptide and mature peptide) and M‐ApCec (just mature peptide) were synthesized chemically and analyzed by HPLC and mass spectroscopy. The antibacterial activity of M‐ApCec is more potent than pro‐ApCec against E. coli K12 or B. subtilus in both minimum inhibitory concentration and inhibition zone assays. Hemolytic assay results showed M‐ApCec possessed a low cytotoxicity to mammalian cells. The secondary structure of M‐ApCec forms α‐helical structure, shown by circular dichroism spectroscopy. Transmission electron microscopy analysis suggested that M‐ApCec killed bacteria by disrupting bacterial cell membrane integrity. Our results indicate ApCec may play an important role in defending from pathogenic bacteria in A. pernyi, and it may be as a potential candidate for applications in antibacterial drug development and agriculture.
    December 23, 2016   doi: 10.1002/arch.21368   open full text
  • The expression patterns of the clock genes period and timeless are affected by photoperiod in the Mediterranean corn stalk borer, Sesamia nonagrioides.
    Dimitrios Kontogiannatos, Theodoros Gkouvitsas, Anna Kourti.
    Archives of Insect Biochemistry and Physiology. December 21, 2016
    To obtain clues to the link between the molecular mechanism of circadian and photoperiod clocks, we cloned two circadian clock genes, period (per) and timeless (tim) from the moth Sesamia nonagrioides, which undergoes facultative diapause controlled by photoperiod. Sequence analysis revealed a high degree of conservation among the compared insects fοr both genes. We also investigated the expression patterns of per and tim in brains of larvae growing under 16L:8D (long days), constant darkness (DD) and 10L:14D (short days) conditions by qPCR assays. The results showed that mRNA accumulations encoding both genes exhibited diel oscillations under different photoperiods. The oscillation of per and tim mRNA, under short‐day photoperiod differed from long‐day. The difference between long‐day and short‐day conditions in the pattern of mRNA levels of per and tim appears to distinguish photoperiodic conditions clearly and both genes were influenced by photoperiod in different ways. We infer that not all photoperiodic clocks of insects interact with circadian clocks in the same fashion. Our results suggest that transcriptional regulations of the both clock genes act in the diapause programing in S. nonagrioides. The expression patterns of these genes are affected by photoperiod but runs with 24 h by entrainment to daily environmental cues.
    December 21, 2016   doi: 10.1002/arch.21366   open full text
  • Green tea polyphenols require the mitochondrial iron transporter, mitoferrin, for lifespan extension in Drosophila melanogaster.
    Terry E. Lopez, Hoang M. Pham, Benjamin V. Nguyen, Yerazik Tahmasian, Shannon Ramsden, Volkan Coskun, Samuel E. Schriner, Mahtab Jafari.
    Archives of Insect Biochemistry and Physiology. October 03, 2016
    Green tea has been found to increase the lifespan of various experimental animal models including the fruit fly, Drosophila melanogaster. High in polyphenolic content, green tea has been shown to reduce oxidative stress in part by its ability to bind free iron, a micronutrient that is both essential for and toxic to all living organisms. Due to green tea's iron‐binding properties, we questioned whether green tea acts to increase the lifespan of the fruit fly by modulating iron regulators, specifically, mitoferrin, a mitochondrial iron transporter, and transferrin, found in the hemolymph of flies. Publicly available hypomorph mutants for these iron regulators were utilized to investigate the effect of green tea on lifespan and fertility. We identified that green tea could not increase the lifespan of mitoferrin mutants but did rescue the reduced male fertility phenotype. The effect of green tea on transferrin mutant lifespan and fertility were comparable to w1118 flies, as observed in our previous studies, in which green tea increased male fly lifespan and reduced male fertility. Expression levels in both w1118 flies and mutant flies, supplemented with green tea, showed an upregulation of mitoferrin but not transferrin. Total body and mitochondrial iron levels were significantly reduced by green tea supplementation in w1118 and mitoferrin mutants but not transferrin mutant flies. Our results demonstrate that green tea may act to increase the lifespan of Drosophila in part by the regulation of mitoferrin and reduction of mitochondrial iron.
    October 03, 2016   doi: 10.1002/arch.21353   open full text
    Abel Trujillo‐Ocampo, Febe Elena Cázares‐Raga, Antonio Celestino‐Montes, Leticia Cortés‐Martínez, Mario H. Rodríguez, Fidel de la Cruz Hernández‐Hernández.
    Archives of Insect Biochemistry and Physiology. September 05, 2016
    The 14‐3‐3 proteins are evolutionarily conserved acidic proteins that form a family with several isoforms in many cell types of plants and animals. In invertebrates, including dipteran and lepidopteran insects, only two isoforms have been reported. 14‐3‐3 proteins are scaffold molecules that form homo‐ or heterodimeric complexes, acting as molecular adaptors mediating phosphorylation‐dependent interactions with signaling molecules involved in immunity, cell differentiation, cell cycle, proliferation, apoptosis, and cancer. Here, we describe the presence of two isoforms of 14‐3‐3 in the mosquito Aedes aegypti, the main vector of dengue, yellow fever, chikungunya, and zika viruses. Both isoforms have the conserved characteristics of the family: two protein signatures (PS1 and PS2), an annexin domain, three serine residues, targets for phosphorylation (positions 58, 184, and 233), necessary for their function, and nine alpha helix‐forming segments. By sequence alignment and phylogenetic analysis, we found that the molecules correspond to Ɛ and ζ isoforms (Aeae14‐3‐3ε and Aeae14‐3‐3ζ). The messengers and protein products were present in all stages of the mosquito life cycle and all the tissues analyzed, with a small predominance of Aeae14‐3‐3ζ except in the midgut and ovaries of adult females. The 14‐3‐3 proteins in female midgut epithelial cells were located in the cytoplasm. Our results may provide insights to further investigate the functions of these proteins in mosquitoes.
    September 05, 2016   doi: 10.1002/arch.21348   open full text
  • Ingestion of the anti‐bacterial agent, gemifloxacin mesylate, leads to increased gst activity and peroxidation products in hemolymph of Galleria mellonella l. (lepidoptera: pyralidae).
    Meltem Erdem, Ceyhun Küçük, Ender Büyükgüzel, Kemal Büyükgüzel.
    Archives of Insect Biochemistry and Physiology. September 02, 2016
    Gemifloxacin mesylate (GEM) is a synthetic, fourth‐generation fluoroquinolone antibacterial antibiotic that has a broad spectrum of activity against bacteria. GEM inhibits DNA synthesis by inhibiting DNA gyrase and topoisomerase IV activities. Recent research into insect nutrition and mass‐rearing programs, in which antibiotics are incorporated into the culture media to maintain diet quality, raised a question of whether clinical antibiotics influence the health or biological performance of the insects that ingest these compounds. Because some antibiotics are pro‐oxidant compounds, we addressed the question with experiments designed to assess the effects of GEM (mesylate salt) on oxidative stress indicators, using Galleria mellonella larvae. The insects were reared from first‐instar larvae to adulthood on artificial diets amended with GEM at 0.001, 0.01, 0.1, or 1.0%. Feeding on the 1% diets led to significantly increased hemolymph contents of the lipid peroxidation product, malondialdehyde and protein oxidation products, protein carbonyl. All GEM concentrations led to increased hemolymph glutathione S‐transferase activity. We inferred that although it was not directly lethal to G. mellonella larvae, dietary exposure to GEM exerts measurable oxidative damage, possibly on insects generally. Long‐term, multigenerational effects remain unknown.
    September 02, 2016   doi: 10.1002/arch.21352   open full text
  • Bmdredd Regulates The Apoptosis Coordinating With Bmdaxx, Bmcide‐B, Bmfadd, And Bmcreb In Bmn Cells.
    Rui‐ting Chen, Peng Jiao, Yan Lu, Hu‐hu Xin, Deng‐pan Zhang, Mei‐xian Wang, Shuang Liang, Yun‐gen Miao.
    Archives of Insect Biochemistry and Physiology. August 25, 2016
    The apoptosis mechanisms in mammals were investigated relatively clearly. However, little is known about how apoptosis is achieved at a molecular level in silkworm cells. We cloned a caspase homologous gene named BmDredd (where Bm is Bombyx mori and Dredd is death‐related ced‐3/Nedd2‐like caspase) in BmN cells from the ovary of Bm and analyzed its biological information. We constructed the N‐terminal, C‐terminal, and overexpression vector of BmDredd, respectively. Our results showed that the transcriptional expression level of BmDredd was increased in the apoptotic BmN cells. Furthermore, overexpression of BmDredd increased the caspase‐3/7 activity. Simultaneously, RNAi of BmDredd could save BmN cells from apoptosis. The immunofluorescence study showed that BmDredd located at the cytoplasm in normal cell otherwise is found at the nucleus when cells undergo apoptosis. Moreover, we quantified the transcriptional expressions of apoptosis‐related genes including BmDredd, BmDaxx (where Daxx is death‐domain associated protein), BmCide‐b (where Cide‐b is cell death inducing DFF45‐like effector), BmFadd (Fadd is fas‐associated via death domain), and BmCreb (where Creb is cAMP‐response element binding protein) in BmN cells with dsRNA interferences to detect the molecular mechanism of apoptosis. In conclusion, BmDredd may function for promoting apoptosis and there are various regulatory interactions among these apoptosis‐related genes.
    August 25, 2016   doi: 10.1002/arch.21349   open full text
  • Dietary Silver Nanoparticles Reduce Fitness In A Beneficial, But Not Pest, Insect Species.
    Zahra Afrasiabi, Holly J.R. Popham, David Stanley, Dhananjay Suresh, Kristen Finley, Jonelle Campbell, Raghuraman Kannan, Anandhi Upendran.
    Archives of Insect Biochemistry and Physiology. August 10, 2016
    Silver nanoparticles (AgNPs) have antimicrobial and insecticidal properties and they have been considered for their potential use as insecticides. While they do, indeed, kill some insects, two broader issues have not been considered in a critical way. First, reports of insect‐lethal AgNPs are often based on simplistic methods that yield nanoparticles of nonuniform shapes and sizes, leaving questions about the precise treatments test insects experienced. Second, we do not know how AgNPs influence beneficial insects. This work addresses these issues. We assessed the influence of AgNPs on life history parameters of two agricultural pest insect species, Heliothis virescens (tobacco budworm) and Trichoplusia ni (cabbage looper) and a beneficial predatory insect species, Podisus maculiventris (spined soldier bug), all of which act in agroecosystems. Rearing the two pest species on standard media amended with AgNPs led to negligible influence on developmental times, pupal weights, and adult emergence, however, they led to retarded development, reductions in adult weight and fecundity, and increased mortality in the predator. These negative effects on the beneficial species, if also true for other beneficial insect species, would have substantial negative implications for continued development of AgNPs for insect pest management programs.
    August 10, 2016   doi: 10.1002/arch.21351   open full text
  • Nonsulfated Sulfakinin Changes Metabolic Parameters Of Insect Fat Body Mitochondria.
    Malgorzata Slocinska, Nina Antos‐Krzeminska, Grzegorz Rosinski, Wieslawa Jarmuszkiewicz.
    Archives of Insect Biochemistry and Physiology. August 08, 2016
    We investigated the effect of neuropeptide, the nonsulfated sulfakinin (SK) Zopat‐SK‐1 (pETSDDYGHLRFa) on the mitochondrial oxidative metabolism in the Zophobas atratus larval fat body. Mitochondria were isolated from beetle fat bodies 2 and 24 h after hormone injection. The administration of 20 pmol of Zopat‐SK‐1 to feeding larvae led to decreased mitochondrial oxidative activities in larval fat body. Diminished activities of citrate synthase and the cytochrome pathway, that is, nonphosphorylating and phosphorylating respiration during succinate oxidation, were observed. However, the effect of Zopat‐SK‐1 was more pronounced in fat body of insects after 24 h since hormone application. In hormone‐treated larval fat bodies, mitochondrial respiration was decreased at the level of respiratory chain and the TCA cycle as well as at the level of mitochondrial biogenesis, as indicated by decreased activities of mitochondrial marker enzymes in fat body homogenates. The inhibition of succinate oxidation may indicate the role of Zopat‐SK‐1 in the regulation of mitochondrial complex II activity. Moreover, decreased respiratory chain activity was accompanied by the reduced activity of mitochondrial energy‐dissipating pathway, uncoupling protein 4. The observed decrease in mitochondrial oxidative metabolism may reflect the Zopat‐SK‐1‐induced reduction in the metabolic rate of larval fat body linked to actual energetic demands of animal.
    August 08, 2016   doi: 10.1002/arch.21350   open full text
    Joseph Woodring, Sandy Weidlich.
    Archives of Insect Biochemistry and Physiology. July 22, 2016
    In Gryllus bimaculatus, the size of the caecum decreases in the latter half of each instar to a stable minimal size with a steady minimal rate of digestive enzyme secretion until feeding resumes after ecdysis. The higher the percent protein in the newly ingested food, the faster and larger the caecum grows, and as a consequent the higher the secretion rate of trypsin and amylase. When hard boiled eggs (40% protein) are eaten the caecum is 2× larger, the trypsin secretion is almost 3× greater, and amylase 2.5× greater then when fed the same amount of apples (1.5% protein). Only dietary protein increases amylase secretion, whereas dietary carbohydrates have no effect on amylase secretion. The minimal caecal size and secretion rate must be supported by utilization of hemolymph amino acids, but the growth of the caecum and increasing enzymes secretions after the molt depend upon an amino acid source in the lumen. This simple regulation of digestive enzyme secretion is ideal for animals that must stop feeding in order to molt. This basic control system does not preclude additional regulation mechanisms, such as prandal, which is also indicated for G. bimaculatus, or even paramonal regulation.
    July 22, 2016   doi: 10.1002/arch.21346   open full text
    Dong‐Ming Wang, Bang‐Xian Zhang, Xiao‐Ming Liu, Xiang‐Jun Rao, Shi‐Guang Li, Mao‐Ye Li, Su Liu.
    Archives of Insect Biochemistry and Physiology. July 22, 2016
    In this study, two full‐length cDNA sequences (Cmace1 and Cmace2) encoding putative acetylcholinesterases (AChEs) were cloned and characterized from the rice leaffolder, Cnaphalocrocis medinalis, an important lepidopteran rice pest in Asia. Cmace1 encodes a CmAChE1 consisting of 689 amino acid residues, while Cmace2 encodes a 639 amino acids CmAChE2. The two CmAChEs both have N‐terminal signal peptides and conserved motifs including the catalytic triad, choline‐binding sites, oxianion hole, acyl pocket, peripheral anionic subsite, and the characteristic FGESAG motif and conserved 14 aromatic amino acids. Phylogenetic analysis showed that Cmace1 and Cmace2 are clustered into distinct clusters that are completely diverged from each other. Reverse‐transcription quantitative PCR analysis revealed that Cmace1 and Cmace2 were predominately expressed in the larval brain and at the fifth‐instar larvae stage, and the transcription levels of Cmace1 were significantly higher than those of Cmace2 in all the tested samples. Recombinant CmAChE1 and CmAChE2 were heterologously expressed in baculovirus system. Using acetylthiocholine iodide (ATChI) as substrate, the Michaelis constant (Km) values of rCmAChE1 and rCmAChE2 were 39.81 ± 6.49 and 68.29 ± 6.72 μmol/l, respectively; and the maximum velocity (Vmax) values of the two rCmAChEs were 0.60 ± 0.02 and 0.31 ± 0.06 μmol/min/mg protein, respectively. Inhibition assay indicated that rCmAChE1 was more sensitive to the organophosphate insecticides chlorpyrifos and triazophos than rCmAChE2. This study is the first report of molecular cloning and biochemical characterization of two acetylcholinesterase genes/enzymes in C. medinalis.
    July 22, 2016   doi: 10.1002/arch.21347   open full text
    Fei Deng, Qiankun He, Zhangwu Zhao.
    Archives of Insect Biochemistry and Physiology. July 13, 2016
    Peroxidases (POXs) make up a large superfamily of enzymes that act in a wide range of biological mechanisms, including maintaining appropriate redox balances within cells, among other actions. In this study, we cloned a sequence that encodes a POX protein, SaPOX, from wheat aphids, Sitobion avenae. Amino acid sequence alignment showed the SaPOX sequence was conserved with POXs from other insect species. SaPOX mRNA accumulations were present in all nymphal and adult stages, at higher levels during the first and second instar, and lower during later stages in the life cycle. Ingestion of dsRNA specific to POX led to reduced SaPOX mRNA accumulation. Sitobion avenae nymphs continuously exposed to dietary dsPOX via an artificial diet led to reduced survival rate and ecdysis index. We infer that POX is important to maintain the growth and development of S. avenae.
    July 13, 2016   doi: 10.1002/arch.21343   open full text
  • Gender Influences Differentiation Of Chitin Among Body Parts.
    Murat Kaya, Esra Bulut, Muhammad Mujtaba, Karolis Sivickis, Idris Sargin, Bahar Akyuz, Sevil Erdogan.
    Archives of Insect Biochemistry and Physiology. July 13, 2016
    Earlier reports have established that chitin isolates from each body part of an insect cuticle can exhibit diverse physicochemical properties. But it is still unknown if the gender of the insect can influence characteristics of chitin isolates from different body parts. The present study addresses this question. As a result, important physicochemical differences in the chitin samples from different body parts of Melolontha sp. were recorded on the basis of sex. The chitin samples were extracted from eight different body parts (antennae, head, eyes, thorax, abdomen, elytra, hindwings, and legs) of female and male. The most remarkable variations in the chitin isolates from female and male body parts were recorded in chitin content, crystallinity, thermal stability, and surface morphology. And also it was wondered these chitin isolates from different body parts of female and male could find different applications. To check this hypothesis, the chitin samples from female and male were interacted with bovine serum albumin (BSA) protein and important variations were observed.
    July 13, 2016   doi: 10.1002/arch.21344   open full text
    Bin‐Bin Wang, Yi Xie, Fan‐Chi Li, Min Ni, Kai‐Zun Xu, Jiang‐Hai Tian, Jing‐Sheng Hu, Bin Xue, Wei‐De Shen, Bing Li.
    Archives of Insect Biochemistry and Physiology. July 12, 2016
    The main mechanism of toxicity of organophosphate (OP) and carbamate (CB) insecticides is their irreversible binding and inhibition of acetylcholinestrase (AChE), encoded by ace1 (acetylcholinestrase gene 1), leading to eventual death of insects. Mutations in AChE may significantly reduce insects susceptibility to these pesticides. Bombyx mori is an important beneficial insect, and no OP‐ or CB‐resistant strains have been generated. In this study, wild‐type ace1 (wace1) and mutant ace1 (mace1) were introduced into BmN cells, confirmed by screening and identification. The expression of wace1 and mace1 in the cells was confirmed by Western blot and their expression levels were about 21‐fold higher than the endogenous ace1 level. The activities of AChE in wace1 and mace1 transgenic cells were 10.6 and 20.2% higher compared to control cells, respectively. mace1 transgenic cells had higher remaining activity than wace1 transgenic cells under the treatment of physostigmine (a reversible cholinesterase inhibitor) and phoxim (an OP acaricide). The results showed that ace1 transgene can significantly improve ace1 expression, and ace1 mutation at a specific site can reduce the sensitivity to AChE inhibitors. Our study provides a new direction for the exploration of the relationship between AChE mutations and drug resistance.
    July 12, 2016   doi: 10.1002/arch.21345   open full text
    Ju‐Hong Zhang, Shang Wang, Shuang Yang, Jiankun Yi, Yan Liu, Jing‐Hui Xi.
    Archives of Insect Biochemistry and Physiology. July 11, 2016
    To understand the olfactory mechanisms of Holotrichia parallela antennae in detecting volatile compounds in the environment, protein profiles of H. parallela antennae were analyzed using two‐dimensional electrophoresis followed by mass spectrometry and bioinformatics analyses. Approximately 1,100 protein spots in silver staining gel were detected. Quantitative image analysis revealed that in total 47 protein spots showed significant changes in different genders of adult antennae. Thirty‐five differentially expressed proteins were identified by Matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI‐TOF/TOF) tandem mass spectrometer, among which 65.7% are involved in carbohydrate and energy metabolism, antioxidant system, transport, and amino acid/nucleotide metabolism. Some proteins identified here have not been reported previously in insect antennae. Identified male‐biased proteins included odorant‐binding protein 4, pheromone‐binding protein‐related protein 2, odorant‐binding protein 14, prophenoloxidase‐I, acyl‐CoA dehydrogenase, aldo‐keto reductase‐like, carbamoyl phosphate synthetase, etc. whereas some proteins are female biased, such as antennae‐rich cytochrome P450, aldehyde dehydrogenase, and putative glutamine synthetase. Alterations in the levels of some proteins were further confirmed by real time polymerase chain reaction (RT‐PCR). The proteomic resources displayed here are valuable for the discovery of proteins from H. parallela antennae.
    July 11, 2016   doi: 10.1002/arch.21338   open full text
    Emiliane Taillebois, Steeve H. Thany.
    Archives of Insect Biochemistry and Physiology. June 30, 2016
    Nicotinic acetylcholine receptors are ligand‐gated ion channels expressed in many insect structures, such as mushroom bodies, in which they play a central role. We have recently demonstrated using electrophysiological recordings that different native nicotinic receptors are expressed in cockroach mushroom bodies Kenyon cells. In the present study, we demonstrated that eight genes coding for cockroach nicotinic acetylcholine receptor subunits are expressed in the mushroom bodies. Quantitative real‐time polymerase chain reaction (PCR) experiments demonstrated that β1 subunit was the most expressed in the mushroom bodies. Moreover, antisense oligonucleotides performed against β1 subunit revealed that inhibition of β1 expression strongly decreases nicotine‐induced currents amplitudes. Moreover, co‐application with 0.5 μM α‐bungarotoxin completely inhibited nicotine currents whereas 10 μM d‐tubocurarine had a partial effect demonstrating that β1‐containing neuronal nicotinic acetylcholine receptor subtypes could be sensitive to the nicotinic acetylcholine receptor antagonist α‐bungarotoxin.
    June 30, 2016   doi: 10.1002/arch.21340   open full text
    Melika Zadeh‐Tahmasebi, Phuong Bui, Andrew Donini.
    Archives of Insect Biochemistry and Physiology. June 30, 2016
    Larvae of Chironomus riparius respond to ion‐poor and brackish water (IPW, BW) conditions by activating ion uptake mechanisms in the anal papillae and reducing ion absorption at the rectum, respectively. The role that the Malpighian tubules play in ion and osmoregulation under these conditions is not known in this species. This study examines rates of fluid secretion and major cation composition of secreted fluid from tubules of C. riparius reared in IPW, freshwater (FW) and BW. Fluid secretion of tubules from FW and BW larvae was similar but tubules from IPW larvae secrete fluid at higher rates, are more sensitive to serotonin stimulation, and the secreted fluid contains less Na+. Therefore in IPW, tubules work in concert with anal papillae to eliminate excess water while conserving Na+ in the hemolymph. Tubules do not appear to play a significant role in ion/osmoregulation under BW. Serotonin immunoreactivity in the nervous system and gastrointestinal tract of larval C. riparius was similar to that seen in mosquito larvae with the exception that the hindgut was devoid of staining. Hemolymph serotonin titer was similar in FW and IPW; hence, serotonin is not responsible for the observed high rates of fluid secretion in IPW. Instead, it is suggested that serotonin may work in a synergistic manner with an unidentified hormonal factor in IPW. Ion transport mechanisms in the tubules of C. riparius are pharmacologically similar to those of other insects.
    June 30, 2016   doi: 10.1002/arch.21342   open full text
    Hafiz Muhammad Tahir, Farva Khizar, Sajida Naseem, Rabia Yaqoob, Khizar Samiullah.
    Archives of Insect Biochemistry and Physiology. June 17, 2016
    Elevated levels of insecticides detoxifying enzymes, such as esterases, glutathione S‐transferases (GSTs), and cytochrome P‐450 monooxygenases, act in the resistance mechanisms in insects. In the present study, levels of these enzymes in the insecticide‐resistant ground spider Pardosa sumatrana (Thorell, 1890) were compared with a susceptible population (control) of the same species. Standard protocols were used for biochemical estimation of enzymes. The results showed significantly higher levels of nonspecific esterases and monooxygenases in resistant spiders compared to controls. The activity of GSTs was lower in the resistant spiders. Elevated levels of nonspecific esterases and monooxygenases suggest their role in metabolic resistance in P. sumatrana. The reduced levels of total protein contents revealed its possible consumption to meet energy demands.
    June 17, 2016   doi: 10.1002/arch.21341   open full text
    Gang Gao, Xiao‐Xia Xu, Jing Yu, Lin‐Miao Li, Wen‐Yan Ju, Feng‐Liang Jin, Shoaib Freed.
    Archives of Insect Biochemistry and Physiology. June 16, 2016
    The proteolytic activation of prophenoloxidase (proPO) is a humoral defense mechanism in insects and crustaceans. Phenoloxidase (PO) is produced as an inactive precursor namely, proPO and is activated via specific proteolytic cleavage by proPO‐activating proteinase. The current research reports two novel serine proteinase genes (PxSP1—768 bp and PxSP2—816 bp) from Plutella xylostella, encoding 255 and 271 amino acid residues, respectively. Tissue distribution analyses by semiquantitative reverse transcription‐PCR (RT‐PCR) revealed the resultant genes to be primarily expressed in the hemocytes, while quantitative‐RT‐PCR (qRT‐PCR) assay showed that transcription level of PxSP1 and PxSP2 increased significantly after injection of the fungal pathogen Beauveria bassiana. Purified recombinant fusion proteins of PxSP2 and PxSP1 were injected to New Zealand white rabbits and polyclonal antibodies were generated with the titers of 1:12,800. After silencing the expression of PxSP2 by RNAi, the PO activity decreased significantly. The results show that PxSP2 is involved in prophenoloxidase activation in P. xylostella.
    June 16, 2016   doi: 10.1002/arch.21337   open full text
    Kai‐Yu Liu, Yu‐Qian Xia, Jing Zhou, Zu‐Wen Chen, Dandan Lu, Ning‐Zhao Zhang, Xu‐Sheng Liu, Hui Ai, Li‐Lin Zhou.
    Archives of Insect Biochemistry and Physiology. May 26, 2016
    Autophagy is not only involved in development, but also has been proved to attend immune response against invading pathogens. Autophagy protein 5 (ATG5) is an important autophagic protein, which plays a crucial role in autophagosome elongation. Although ATG5 has been well studied in mammal, yeast, and Drosophila, little is known about ATG5 in lepidopteran insects. We cloned putative SeAtg5 gene from Spodoptera exigua larvae by the rapid amplification of cDNA ends method, and its characteristics and the influences of multiple exogenous factors on its expression levels were then investigated. The results showed that the putative S. exigua SeATG5 protein is highly homologous to other insect ATG5 proteins, which has a conserved Pfm domain and multiple phosphorylation sites. Next, fluorescence microscope observation showed that mCherry‐SeATG5 was distributed in both nucleus and cytoplasm of Spodoptera litura Sl‐HP cells and partially co‐localized with BmATG6‐GFP, but it almost has no significant co‐localization with GFP‐HaATG8. Then, the Western blot analysis demonstrated that GFP‐SeATG5 conjugated with ATG12. Moreover, real‐time PCR revealed that its expression levels significantly increased at the initiation of pupation and the stage of adult. In addition, the expression levels of SeAtg5 can be enhanced by the starvation, UV radiation, and infection of baculovirus and bacterium. However, the expression levels of SeAtg5 decreased at 24 h post treatments in all these treatments except in starvation. These results suggested that SeATG5 might be involved in response of S. exigua under various stress conditions.
    May 26, 2016   doi: 10.1002/arch.21339   open full text
    André Fernando Ditondo Micas, Germano Aguiar Ferreira, Helen Julie Laure, José Cesar Rosa, Márcia Maria Gentile Bitondi.
    Archives of Insect Biochemistry and Physiology. May 10, 2016
    The integument of insects and other arthropods is composed of an inner basal lamina coated by the epidermis, which secretes the bulk of the outer integument layer, the cuticle. The genome sequencing of several insect species has allowed predicting classes of proteins integrating the cuticle. However, only a small proportion of them, as well as other proteins in the integumentary system, have been validated. Using two‐dimensional gel electrophoresis coupled with mass spectrometry, we identified 45 different proteins in a total of 112 selected gel spots derived from thoracic integument samples of developing honeybee workers, including 14 cuticular proteins (AmelCPR 3, AmelCPR 12, AmelCPR 16, AmelCPR 27, apidermin 2, apidermin 3, endocuticle structural glycoprotein SgAbd‐8‐like, LOC100577363, LOC408365, LOC413679, LOC725454, LOC100576916, LOC725838, and peritrophin 3‐C analogous). Gene ontology functional analysis revealed that the higher proportions of the identified proteins have molecular functions related to catalytic and structural molecule activities, are involved in metabolic biological processes, and pertain to the protein class of structural or cytoskeletal proteins and hydrolases. It is noteworthy that 26.7% of the identified proteins, including five cuticular proteins, were revealed as protein species resulting from allelic isoforms or derived from posttranslational modifications. Also, 66.7% of the identified cuticular proteins were expressed in more than one developmental phase, thus indicating that they are part of the larval, pupal, and adult cuticle. Our data provide experimental support for predicted honeybee gene products and new information on proteins expressed in the developing integument.
    May 10, 2016   doi: 10.1002/arch.21336   open full text
    Andres F. Sandoval‐Mojica, Michael E. Scharf.
    Archives of Insect Biochemistry and Physiology. April 18, 2016
    The peritrophic matrix (PM) is an acellular structure that lines the gut of most insects. It is an attractive target for pest management strategies because of its close involvement in digestive processes and role as a barrier against pathogens and toxins. The purpose of this study was to identify and characterize the genes that translate for principal components of the Reticulitermes flavipes PM. Genes encoding a gut chitin synthase (CHS), two proteins with peritrophin‐A domains, and a chitin deacetylase were identified from an R. flavipes symbiont‐free gut cDNA library, a pyrosequencing study of termite lignocellulose digestion, and a metatranscriptomic analysis of R. flavipes fed on agricultural biomass. Quantitative expression analysis of the identified genes, in the termite digestive tract, revealed that the transcripts coding for a CHS (RfCHSB) and the proteins with peritrophin‐A domains (RfPPAD1 and RfPPAD2) were predominantly expressed in the midgut, suggesting an association with the PM. The peritrophin identity of the RfPPAD2 gene was confirmed by immunodetection of its translated peptide in the midgut and PM. The discovery and characterization of PM components of R. flavipes provides a basis for further investigation of the viability of this structure as a target for candidate termiticides.
    April 18, 2016   doi: 10.1002/arch.21325   open full text
    Ting Li, Yan Liu, Dan‐Dan Wei, Feng Shang, Guy Smagghe, Wei Dou, Jin‐Jun Wang, Guy Smagghe.
    Archives of Insect Biochemistry and Physiology. April 18, 2016
    In this study, the cDNAs of five cytochromes P450 genes (named CYP345P1, CYP358B1, CYP4FD2, CYP4CD2, and CYP6JN1) contained open reading frames from 1,500 to 1,554 nucleotides that encoded 499 to 517 amino acids were cloned from the psocid Liposcelis entomophila. They are characterized by predicted molecular weights from 57.67 to 59.64 kDa and theoretical isoelectric points of 5.57–9.07. Quantitative real‐time PCR analysis showed these five genes were expressed at all tested developmental stages and higher expressions were observed in adults. CYP358B1 was expressed at higher levels in egg and adult compared to the larval stages. mRNA abundances of five genes were detected in both sexes and were relatively more abundant in adult females than in adult males. Synergism bioassay showed that the synergic ratio was 2.20 and 2.45 when insects were treated with the mixture of deltamethrin or malathion with the synergist piperonyl butoxide (PBO). Because PBO induces cytochrome P450s in some insects, this suggested to us that cytochromes P450 might participate in detoxification of these insecticides. The transcripts of the five cytochromes P450 genes in adult psocids could be induced to the highest level at 12 h after the exposure to malathion. After exposure to deltamethrin, CYP358B1 reached maximum expression at 24 h. The maximum expression of the other four genes occurred at 36 h. Treatments with the carbamate propoxur did not influence transcription of the cytochromes P450 gene. The induction profiles suggested that these five cytochrome P450 genes may be associated with deltamethrin and malathion metabolism in psocids.
    April 18, 2016   doi: 10.1002/arch.21333   open full text
  • Larval X‐Ray Irradiation Influences Protein Expression In Pupae Of The Oriental Fruit Fly, Bactrocera Dorsalis.
    Chiou Ling Chang, Cynthia L. Goodman, Joseph Ringbauer, Scott M. Geib, David Stanley.
    Archives of Insect Biochemistry and Physiology. April 15, 2016
    The sterile insect technique (SIT) was developed to eradicate the new world screwworm from the southern United States and Mexico, and became a component of many area‐wide integrated pest management programs, particularly useful in managing tephritid fruit flies. SIT is based on the idea of rearing and sterilizing male pests, originally by ionizing radiation, and then releasing into field, where they compete for and mate with wild females. Mating with sterile males leads to reduced fecundity to lower pest populations. There are concerns with the use and distribution of radioisotopes for SIT programs, which have led to developing X‐ray irradiation protocols to sterilize insects. We considered the possibility that X‐ray irradiation exerts sublethal impacts aside form sterilizing insects. Such effects may not be directly observable, which led us to the hypothesis that X‐ray irradiation in one life stage creates alterations in biological fitness and protein expression in the subsequent stage. We tested our hypothesis by irradiating larvae of Bactrocera dorsalis. There are two major points. One, exposing larvae to X‐ray treatments led to reduced adult emergence, fecundity, fertility, and flight capacity from the corresponding pupae and emerged adults. Two, the X‐ray treatments led to substantial expression changes in 27 pupal proteins. We assorted the 67 spots representing these proteins into three groups, metabolism, development, and structure. Our interpretation is these X‐ray induced changes in biological performance and protein expression indicate their adult counterparts may be disabled in their abilities to successfully compete for and mate wild females in native habitats.
    April 15, 2016   doi: 10.1002/arch.21330   open full text
    Kithalakshmi Vignesvaran, Zazali Alias.
    Archives of Insect Biochemistry and Physiology. April 14, 2016
    Drosophila melanogaster glutathione S‐transferase D3 (DmGSTD3) has a shorter amino acid sequence as compared to other GSTs known in the fruit flies. This is due to the 15 amino acid N‐terminal truncation in which normally active amino acid residue is located. The work has made use of homology modeling to visualize the arrangement of amino acid side chains in the glutathione (GSH) substrate cavity. The identified amino acids were then replaced with amino acids without functional groups in the side chains and the mutants were analyzed kinetically. Homology modeling revealed that the side chains of Y89 and Y97 were shown facing toward the substrate cavity proposing their possible role in catalyzing the conjugation. Y97A and Y89A GSH gave large changes in Km (twofold increase), Vmax (fivefold reduction), and Kcat/Km values for GSH suggesting their significant role in the conjugation reaction. The replacement at either positions has not affected the affinity of the enzyme toward 1‐chloro‐2,4‐dinitrobenzene as no significant change in values of Kmax was observed. The replacement, however, had significantly reduced the catalytic efficiency of both mutants with (Kcat/Km)GSH and (Kcat/Km)CDNB of eight‐ and twofold reduction. The recombinant DmGSTD3 has shown no activity toward 1,2‐dichloro‐4‐nitrobenzene, 2,4‐hexadienal, 2,4‐heptadienal, p‐nitrobenzyl chloride, ethacrynic acid, and sulfobromophthalein. Therefore, it was evident that DmGSTD3 has made use of distal amino acids Y97 and Y89 for GSH conjugation.
    April 14, 2016   doi: 10.1002/arch.21332   open full text
    Ji‐Feng Shi, Li‐Li Mu, Wen‐Chao Guo, Guo‐Qing Li.
    Archives of Insect Biochemistry and Physiology. March 31, 2016
    Chitin synthase (ChS) plays a critical role in chitin synthesis and excretion. In this study, two ChS genes (LdChSA and LdChSB) were identified in Leptinotarsa decemlineata. LdChSA contains two splicing variants, LdChSAa and LdChSAb. Within the first, second, and third larval instars, the mRNA levels of LdChSAa, LdChSAb, and LdChSB coincide with the peaks of circulating 20‐hydroxyecdysone (20E) and juvenile hormone (JH). In vitro culture of midguts and an in vivo bioassay revealed that 20E and an ecdysteroid agonist halofenozide stimulated the expression of the three LdChSs. Conversely, a reduction of 20E by RNA interference (RNAi) of an ecdysteroidogenesis gene LdSHD repressed the expression of these LdChSs, and ingestion of halofenozide by LdSHD RNAi larvae rescued the repression. Moreover, disruption of 20E signaling by RNAi of LdEcR, LdE75, LdHR3, and LdFTZ‐F1 reduced the expression levels of these genes. Similarly, in vitro culture and an in vivo bioassay showed that exogenous JH and a JH analog methoprene activated the expression of the three LdChSs, whereas a decrease in JH by RNAi of a JH biosynthesis gene LdJHAMT downregulated these LdChSs. It seems that JH upregulates LdChSs at the early stage of each instar, whereas a 20E pulse triggers the transcription of LdChSs during molting in L. decemlineata.
    March 31, 2016   doi: 10.1002/arch.21331   open full text
  • Involvement Of Peptidoglycan Recognition Protein L6 In Activation Of Immune Deficiency Pathway In The Immune Responsive Silkworm Cells.
    Hiromitsu Tanaka, Aki Sagisaka.
    Archives of Insect Biochemistry and Physiology. March 18, 2016
    The immune deficiency (Imd) signaling pathway is activated by Gram‐negative bacteria for producing antimicrobial peptides (AMPs). In Drosophila melanogaster, the activation of this pathway is initiated by the recognition of Gram‐negative bacteria by peptidoglycan (PGN) recognition proteins (PGRPs), PGRP‐LC and PGRP‐LE. In this study, we found that the Imd pathway is involved in enhancing the promoter activity of AMP gene in response to Gram‐negative bacteria or diaminopimelic (DAP) type PGNs derived from Gram‐negative bacteria in an immune responsive silkworm cell line, Bm‐NIAS‐aff3. Using gene knockdown experiments, we further demonstrated that silkworm PGRP L6 (BmPGRP‐L6) is involved in the activation of E. coli or E. coli‐PGN mediated AMP promoter activation. Domain analysis revealed that BmPGRP‐L6 contained a conserved PGRP domain, transmembrane domain, and RIP homotypic interaction motif like motif but lacked signal peptide sequences. BmPGRP‐L6 overexpression enhances AMP promoter activity through the Imd pathway. BmPGRP‐L6 binds to DAP‐type PGNs, although it also binds to lysine‐type PGNs that activate another immune signal pathway, the Toll pathway in Drosophila. These results indicate that BmPGRP‐L6 is a key PGRP for activating the Imd pathway in immune responsive silkworm cells.
    March 18, 2016   doi: 10.1002/arch.21326   open full text
    Xiaoqun Zhou, Dong Fan, Kuijun Zhao.
    Archives of Insect Biochemistry and Physiology. March 14, 2016
    Two cDNA sequences encoding a trypsin‐like and a chymotrypsin‐like serine protease (MsT and MsCT, GenBank accession Nos. KP730443 and KP730444, respectively) were cloned from midgut of oriental armyworm, Mythimna separata Walker. Multiple alignments revealed that the deduced amino acid sequences of MsT and MsCT contained a serine protease catalytic motif GDSGGPL and catalytic triads (His, Asp, and Ser). Analyses of tissue and developmental expression of MsT and MsCT showed that they were mainly expressed in midguts and could be detected in first to sixth instar larvae, prepupal and pupal stages. Expressions of both MsT and MsCT were downregulated after 24 h of starvation and upregulated by subsequent insect refeeding. MsT expression in response to 20‐hydroxyecdysone (20E) was dose dependent and upregulated after 24 h. However, MsCT expression in response to 20E was downregulated compared with controls. MsCT, but not MsT, transcripts were upregulated after 24 h of Cry1Ac protoxin exposure. These results suggested that MsT was most likely involved in food protein digestion and molting in M. separata whereas MsCT was most likely involved in food protein digestion and Bacillus thuringiensis (Bt) protoxin activation. RNA interference indicated that MsT and MsCT expression levels decreased 76.7 and 86.2% after treated with MsT and MsCT dsRNA, respectively. This study showed that M. separata expressed midgut proteases in line with known lepidopteran counterparts and contributed valuable sequence resource information regarding insect proteases.
    March 14, 2016   doi: 10.1002/arch.21324   open full text
    John E. Steele.
    Archives of Insect Biochemistry and Physiology. March 02, 2016
    Ecdysis in insects can be defined as shedding of the cuticle at the end of a larval stadium. This event can only occur after the peak titer of ecdysteroid in the hemolymph has returned to a low level. In the cockroach Periplaneta americana, ecdysis is strongly correlated with a rise in the concentration of trehalose and glucose in the hemolymph, leading to the idea that a causal relationship may exist between both events. The objective in this study was to determine if an increase in hemolymph sugar level would shorten the time to ecdysis in cockroach larvae with experimentally delayed ecdysis. The last larval stadium of P. americana averages 33.5 days but this increases significantly if the larva is injected with a small volume of saline. Injection of 10 μl of saline on day 20 and on four successive days lengthened the stadium by as much as 2 weeks. If, however, trehalose or glucose is incorporated into the saline, approximately 40% of the treated larvae undergo ecdysis at the same time as uninjected larvae. Injection of Peram‐AKH, the hypertrehalosemic hormone, also decreases the time for ecdysis to occur. This suggests that peak levels of ecdysteroid trigger the release of Peram‐AKH, which then leads to activation of trehalose synthesis. The results support the hypothesis that elevated hemolymph sugar is a contributing factor in the removal of ecdysteroid from the hemolymph.
    March 02, 2016   doi: 10.1002/arch.21323   open full text
    Colin S. Brent, Meixian Wang, Yun‐Gen Miao, J. Joe Hull.
    Archives of Insect Biochemistry and Physiology. February 26, 2016
    Vital physiological processes that drive the insect molt represent areas of interest for the development of alternative control strategies. The western tarnished plant bug (Lygus hesperus Knight) is a pest of numerous agronomic and horticultural crops but the development of novel control approaches is impeded by limited knowledge of the mechanisms regulating its molt. To address this deficiency, we examined the fundamental relationship underlying the hormonal and molecular components of ecdysis. At 27°C L. hesperus exhibits a temporally controlled nymph–adult molt that occurs about 4 days after the final nymph–nymph molt with ecdysteroid levels peaking 2 days prior to the final molt. Application of exogenous ecdysteroids when endogenous levels had decreased disrupted the nymphal–adult molt, with treated animals exhibiting an inability to escape the old exoskeleton and resulting in mortality compared to controls. Using accessible transcriptomic data, we identified 10 chitinase‐like sequences (LhCht), eight of which had protein motifs consistent with chitinases. Phylogenetic analyses revealed orthologous relationships to chitinases critical to molting in other insects. RT‐PCR based transcript profiling revealed that expression changes to four of the LhChts was coordinated with the molt period and ecdysteroid levels. Collectively, our results support a role for ecdysteroid regulation of the L. hesperus molt and suggest that cuticle clearance is mediated by LhCht orthologs of chitinases that are essential to the molt process. These results provide the initial hormonal and molecular basis for future studies to investigate the specific roles of these components in molting.
    February 26, 2016   doi: 10.1002/arch.21322   open full text
  • Wasp‐Associated Factors Act In Interspecies Competition During Multiparasitism.
    Peter M. Magdaraog, Toshiharu Tanaka, Jeffrey A. Harvey.
    Archives of Insect Biochemistry and Physiology. February 18, 2016
    Coexistence or displacement of parasitoids in hosts during intrinsic competitive interactions between different parasitoid species (multiparasitism) may depend on their life history traits and behavior. Intense competition for possession of hosts may lead to the elimination of the inferior competitor through physical attack and/or physiological suppression. However, the mechanisms of physiological suppression during multiparasitism remain unclear. Previous work has shown that first instar larvae of the solitary endoparasitoid Meteorus pulchricornis possess well‐developed mandibles that are used to kill competitors. Two gregarious endoparasitoids, Cotesia kariyai and C. rufricus, share host resources especially when the time gap of oviposition is short. Here, we investigated the physiological influence of wasp‐regulatory factors of the three endoparasitoids, M. pulchricornis, C. kariyai, and C. ruficrus, in their common host Mythimna separata. We found that MpVLP alone (or with venom) deleteriously affected the development of the two gregarious species. Similarly, CkPDV plus venom had toxic effect on M. pulchricornis eggs and immature larvae, although they were not harmful to immature stages of C. ruficrus. Cotesia kariyai and C. ruficrus were able to coexist mainly through the expression of regulatory factors and both could successfully emerge from a multiparasitized host. The injection of CkPDV plus venom after oviposition in L5 host larvae facilitated C. ruficrus development and increased the rate of successful parasitism from 9% to 62%. This suggests that the two gregarious parasitoid wasps exhibit strong phylogenetic affinity, favoring their coexistence and success in multiparasitized hosts.
    February 18, 2016   doi: 10.1002/arch.21321   open full text
    Franziska Wende, Martina Meyering‐Vos, Klaus H. Hoffmann.
    Archives of Insect Biochemistry and Physiology. October 29, 2015
    Allatostatins with the C‐terminal ending Tyr/Phe‐Xaa‐Phe‐Gly‐Leu/Ile‐amide (FGLa/ASTs) are widespread neuropeptides with multiple functions. The gene encoding the FGLa/AST polypeptide precursor was first isolated from cockroaches and since then could be identified in many insects and crustaceans. With its strictly conserved regions in combination with variable regions the gene seems to be a good candidate for phylogenetic analyses between closely and distantly related species. Here, the structure of the FGLa/AST gene of the most primitive termite, the giant northern termite Mastotermes darwiniensis Froggatt, was identified. The FGLa/AST gene of the woodroach Cryptocercus darwini was also determined. Precursor sequences of both species possess the general organization of dictyopteran FGLa/AST precursors containing 14 putative FGLa/AST peptides. In M. darwiniensis, only 11 out of the 14 FGLa/AST‐like peptides possess the C‐terminal conserved region Y/FXFGL/I/V/M and four of the putative peptide structures are not followed by a Gly residue that would lead to nonamidated peptides. Phylogenetic analyses show the high degree of similarity of dictyopteran FGLa/AST sequences. The position of termites, nested within the Blattaria, confirms that termites have evolved from primitive cockroaches.
    October 29, 2015   doi: 10.1002/arch.21310   open full text
    Yi‐Jun Zhou, Bin Xue, Yang‐Yang Li, Fan‐Chi Li, Min Ni, Wei‐De Shen, Zhi‐Ya Gu, Bing Li, Wei‐De Shen, Zhi‐Ya Gu, Bing Li.
    Archives of Insect Biochemistry and Physiology. October 16, 2015
    Silkworm is an important economic insect and the model species for Lepidoptera. The midgut of silkworm is an important physiological barrier, as its peritrophic membrane (PM) can resist pathogen invasion. In this study, a silkworm midgut cDNA library was constructed in order to identify silkworm PM genes. The capacity of the initial library was 6.92 × 106 pfu/ml, along with a recombination rate of 92.14% and a postamplification titer of 4.10 × 109 pfu/ml. Three silkworm PM protein genes were obtained by immunoscreening, two of which were chitin‐binding protein (CBP) genes and one of which was a chitin deacetylase (CDA) gene as revealed by sequence analysis. Three genes were named BmCBP02, BmCBP13, and BmCDA17, and their ORF sizes are 678, 1,029, and 645 bp, respectively; all of them contain sequences of chitin‐binding domains. Phylogenetic analysis indicated that BmCBP02 has the highest consensus with Mamestra configurata CBP at 61.0%; BmCBP13 has the highest consensus with Loxostege sticticalis PM CBP at 53.35%; BmCDA17 has the highest consensus with Helicoverpa armigera CDA5a at 70.83%. Tissue transcriptional analysis revealed that all three genes were specifically expressed in the midgut, and during the developmental process of fifth‐instar silkworms, the transcription of all the genes showed an upward trend. This study laid a foundation for further studies on the functions of silkworm PM genes.
    October 16, 2015   doi: 10.1002/arch.21305   open full text
    Oleh V. Lushchak, Dmytro V. Gospodaryov, Ihor S. Yurkevych, Kenneth B. Storey.
    Archives of Insect Biochemistry and Physiology. October 08, 2015
    Aging is often associated with accumulation of oxidative damage in proteins and lipids. However, some studies do not support this view, raising the question of whether high levels of oxidative damage are associated with lifespan. In the current investigation, Drosophila melanogaster flies were kept on diets with 2 or 10% of either glucose or fructose. The lifespan, fecundity, and feeding as well as amounts of protein carbonyls (PC) and lipid peroxides (LOOH), activities of superoxide dismutase (SOD), catalase, glutathione‐S‐transferase (GST), and glutathione reductase activity of thioredoxin reductase (TrxR) were measured in “young” (10‐day old) and “aged” (50‐day old) flies. Flies maintained on diets with 10% carbohydrate lived longer than those on the 2% diets. However, neither lifespan nor fecundity was affected by the type of carbohydrate. The amount of PC was unaffected by diet and age, whereas flies fed on diets with 10% carbohydrate had about fivefold higher amounts of LOOH compared to flies maintained on the 2% carbohydrate diets. Catalase activity was significantly lower in flies fed on diets with 10% carbohydrates compared to flies on 2% carbohydrate diets. The activities of SOD, GST, and TrxR were not affected by the diet or age of the flies. The higher levels of LOOH in flies maintained on 10% carbohydrate did not reduce their lifespan, from which we infer that oxidative damage to only one class of biomolecules, particularly lipids, is not sufficient to influence lifespan.
    October 08, 2015   doi: 10.1002/arch.21308   open full text
    Yan‐Ru Zhou, Lin‐Ying Li, Jun‐Min Li, Zong‐Tao Sun, Li Xie, Jian‐Ping Chen.
    Archives of Insect Biochemistry and Physiology. October 08, 2015
    Argonaute (AGO) proteins are essential catalytic components of the RNA‐induced silencing complex and play central roles in RNA interference. Using a combination of bioinformatics and rapid amplification of cDNA ends (RACE) methods, putative AGO subfamily members, ls‐AGO1 and ls‐AGO2, were cloned and characterized from the small brown planthopper, Laodelphax striatellus. The open reading frame (ORF) of ls‐AGO1 is 2,820 bp long, encoding a putative protein of 939 amino acid residues, and ls‐AGO2 contains an ORF of 2,490 bp, encoding 829 amino acid residues. The expected conserved PAZ and PIWI domains, and the conserved Asp–Asp–His (DDH) catalytic triad motif in the PIWI domain were observed in both ls‐AGO1 and ls‐AGO2. Reverse transcription‐qPCR (RT‐qPCR) results showed that both ls‐AGO1 and ls‐AGO2 were expressed in all developmental stages of L. striatellus with highest mRNA abundance in eggs. Expression of ls‐AGO1 and ls‐AGO2 was significantly decreased in adult insects in response to acquisition of rice black‐streaked dwarf virus by second instar nymphs. mRNA expression of ls‐AGO1 was significantly downregulated in response to low and high temperatures, but expression of ls‐AGO2 was only affected by low temperature. ls‐AGO1 and ls‐AGO2 were initially downregulated when insects were transferred from rice to maize and to the wild grass Brachypodium distachyon, but expression showed partial or complete recovery 7 days after transfer. These results document that AGO subfamily members of L. striatellus are ubiquitously expressed at different developmental stages and respond to various stresses. Thus, AGO subfamily may act in regulating the stress–response of L. striatellus by controlling related gene expression.
    October 08, 2015   doi: 10.1002/arch.21307   open full text
    Sandy Weidlich, Klaus H. Hoffmann, Joseph Woodring.
    Archives of Insect Biochemistry and Physiology. October 08, 2015
    Little is known concerning the sites and the ratios of the lipase secretions in insects, therefore we undertook an examination of the lipase secretion of fed and unfed adult female Gryllus bimaculatus. The ratio of triacylglyceride lipase, diacylglyceride lipase, and phosphatidylcholine lipase secreted by fed females in the caecum and ventriculus is 1:1.4:0.4. These activities decrease in the caecum by 30–40% in unfed females. The total lipase activity (TLA) in the caecum is about 10 times that in the ventriculus. Minimal lipase secretion occurs before and during the final moult, and remains at this level in unfed crickets, indicating a basal secretion rate. In 2‐day‐old fed females, about 10% of the TLA in the entire gut is found in the crop, about 70% in the caecum, 20% in the ventriculus, and 3% in the ileum. Lipases in the ventriculus are recycled back to the caecum and little is lost in the feces. Oleic acid stimulated in vitro lipase secretion, but lipids did not. Feeding stimulated lipase secretion, starvation reduced lipase secretion, but this does not prove a direct prandal regulation of secretion, because feeding also induced a size and volume increase of the caecum.
    October 08, 2015   doi: 10.1002/arch.21303   open full text
    Qingli Shang, Yiou Pan, Tianfei Peng, Shuang Yang, Xin Lu, Zhenying Wang, Jinghui Xi.
    Archives of Insect Biochemistry and Physiology. October 06, 2015
    Many insects in temperate regions overwinter in diapause. In these insects, one of the metabolic adaptations to cold stress is the synthesis of responsive proteins. Using proteomic analysis, an investigation aimed to a better understanding of the molecular adaptation mechanisms to cold stress was carried out in Ostrinia furnacalis larva. Proteins were extracted from the larval hemolymph collected from both control and overwintering larva. By polyethylene glycol precipitation, approximately 560 protein spots were separated and visualized on two‐dimensional (2D) gels after silver staining. Eighteen protein spots were found to be upregulated in overwinter larval plasma in different patterns. As an initial work, 13 of these proteins were identified using MALDI TOF/TOF MS. The differentially overexpressed proteins include heat shock 70 kDa cognate protein, small heat shock protein (sHSP), putative aliphatic nitrilase, arginine kinase, phosphoglyceromutase, triosephosphateisomerase, and glutathione transferase. Alterations in the levels of these proteins were further confirmed by qPCR. This study is the first analysis of differentially expressed plasma proteins in O. furnacalis diapause larvae under extremely low temperature conditions and gives new insights into the acclimation mechanisms responsive to cold stress. Our results also support the idea that energy metabolism, alanine and proline metabolism, and antioxidative reaction act in the cold acclimation of O. furnacalis diapause larvae.
    October 06, 2015   doi: 10.1002/arch.21302   open full text
    Dov Borovsky, Andeas Sterner, Charles A. Powell.
    Archives of Insect Biochemistry and Physiology. October 06, 2015
    The insect peptide hormone trypsin modulating oostatic factor (TMOF), a decapeptide that is synthesized by the mosquito ovary and controls the translation of the gut's trypsin mRNA was cloned and expressed in the marine alga Chlorella desiccata. To express Aedes aegypti TMOF gene (tmfA) in C. desiccata cells, two plasmids (pYES2/TMOF and pYDB4‐tmfA) were engineered with pKYLX71 DNA (5 Kb) carrying the cauliflower mosaic virus (CaMV) promoter 35S2 and the kanamycin resistant gene (neo), as well as, a 8 Kb nitrate reductase gene (nit) from Chlorella vulgaris. Transforming C. desiccata with pYES2/TMOF and pYDB4‐tmfA show that the engineered algal cells express TMOF (20 ± 4 μg ± SEM and 17 ± 3 μg ± SEM, respectively in 3 × 108 cells) and feeding the cells to mosquito larvae kill 75 and 60% of Ae. aegypti larvae in 4 days, respectively. Southern and Northern blots analyses show that tmfA integrated into the genome of C. desiccata by homologous recombination using the yeast 2 μ circle of replication and the nit in pYES2/TMOF and pYDB4‐tmfA, respectively, and the transformed algal cells express tmfA transcript. Using these algal cells it will be possible in the future to control mosquito larvae in the marsh.
    October 06, 2015   doi: 10.1002/arch.21306   open full text
  • Environmental Effects On Superoxide Dismutase And Catalase Activity And Expression In Honey Bee.
    Tatjana V. Nikolić, Jelena Purać, Snežana Orčić, Danijela Kojić, Dragana Vujanović, Zoran Stanimirović, Ivan Gržetić, Konstantin Ilijević, Branko Šikoparija, Duško P. Blagojević.
    Archives of Insect Biochemistry and Physiology. August 28, 2015
    Understanding the cellular stress response in honey bees will significantly contribute to their conservation. The aim of this study was to analyze the response of the antioxidative enzymes superoxide dismutase and catalase in honey bees related to the presence of toxic metals in different habitats. Three locations were selected: (i) Tunovo on the mountain Golija, as control area, without industry and large human impact, (ii) Belgrade as urban area, and (iii) Zajača, as mining and industrial zone. Our results showed that the concentrations of lead (Pb) in whole body of bees vary according to habitat, but there was very significant increase of Pb in bees from investigated industrial area. Bees from urban and industrial area had increased expression of both Sod1 and Cat genes, suggesting adaptation to increased oxidative stress. However, in spite increased gene expression, the enzyme activity of catalase was lower in bees from industrial area suggesting inhibitory effect of Pb on catalase.
    August 28, 2015   doi: 10.1002/arch.21253   open full text
    Kai‐Yun Fu, Feng‐Gong Lü, Wen‐Chao Guo, Guo‐Qing Li.
    Archives of Insect Biochemistry and Physiology. August 17, 2015
    Juvenile hormone diol kinase (JHDK) is an enzyme involved in JH degradation. In the present article, a putative JHDK cDNA (LdJHDK) was cloned from the Colorado potato beetle Leptinotarsa decemlineata. The cDNA consists of 814 bp, containing a 555 bp open reading frame encoding a 184 amino acid protein. LdJHDK reveals a high degree of identity to the previously reported insect JHDKs. It possesses three conserved purine nucleotide‐binding elements, and contains three EF‐hand motifs (helix‐loop‐helix structural domains). LdJHDK mRNA was mainly detected in hindgut and Malpighian tubules. Besides, a trace amount of LdJHDK mRNA was also found in thoracic muscles, brain–corpora cardiaca–corpora allata complex, foregut, midgut, ventral ganglia, fat body, epidermis, and hemocytes. Moreover, LdJHDK was expressed throughout all developmental stages. Within the first, second, and third larval instar, the expression levels of LdJHDK were higher just before and right after the molt, and were lower in the intermediate instar. In the fourth larval instar, the highest peak of LdJHDK occurred 56 h after ecdysis. Ingestion of double‐stranded RNA (dsRNA) against LdJHDK successfully knocked down the target gene, increased JH titer, and significantly upregulated LdKr‐h1 mRNA level. Knockdown of LdJHDK significantly impaired adult emergence. Thus, we provide a line of experimental evidence in L. decemlineata to support that LdJHDK encodes function protein involved in JH degradation.
    August 17, 2015   doi: 10.1002/arch.21251   open full text
    Wei‐Jen Lin, Ching‐Yi Chien, Cheng‐Lung Tsai, Mei‐Er Chen.
    Archives of Insect Biochemistry and Physiology. August 17, 2015
    The yolk protein precursor, vitellogenin (Vg), is absorbed into growing oocytes via receptor‐mediated endocytosis for embryonic development. In this study, a Vg receptor (VgR) cDNA of the oriental fruit fly (Bactrocera dorsalis Hendel) was cloned via RT‐PCR and RACE (GenBank accession no. KR535603) and its expression analyzed. The BdVgR cDNA has a length of 6,585 bp encoding 1,923 amino acids. It has a conserved motif arrangement with other insect VgRs, and showed high identity to the B. cucurbitae VgR (91.4%). The expression of BdVgR mRNA and proteins was shown in both ovary and fat body. This is the first report on a nonovary‐specific VgR from a nonsocial insect. In ovary, the expression of BdVgR mRNA and proteins was inconsistent, with the transcription, but not protein, level high on D0. In fat body, the expression levels of BdVgR mRNA and proteins were high on days 5 and 6. The function of BdVgR in the fat body is not clear. However, it may be involved in reuptake of yolk proteins from the hemolymph as an amino acid reservoir or as autocrine regulation of yolk protein expression.
    August 17, 2015   doi: 10.1002/arch.21252   open full text
    Yu Zhu, Qi Fang, Yang Liu, Ling‐Feng Gao, Zhi‐Chao Yan, Gong‐Yin Ye.
    Archives of Insect Biochemistry and Physiology. August 04, 2015
    The small cabbage butterfly, Pieris rapae, is an important pest of cruciferous corps, and Pteromalus puparum is a predominant pupal endoparasitoid wasp of this butterfly. For successful development of parasitoid offspring, female parasitoids usually introduce one or several kinds of maternal factors into the hemocoels during oviposition to suppress host immunity. To investigate the early changes in host immune‐related genes following parasitization, we analyzed transcriptomes of parasitized and unparasitized, control, host pupae. Approximately 17.7 and 19.3 million paired‐end reads were generated from nonparasitized and parasitized host pupae, and assembled de novo into 45,639 transcripts and 27,659 nonredundant unigenes. The average unigene length was 790 bp. A total 18,377 of 27,659 unigenes were annotated and we identified 557 differentially expressed unigenes in host pupae at 1 h after parasitization, of which 21 were immune‐related. Parasitization led to downregulation of most pattern recognition receptors and upregulation of all serine protease inhibitors. The transcirptomic profile of P. rapae is considerably affected by parasitization. This study provides valuable sources for future investigations of the molecular interaction between P. puparum and its host P. rapae.
    August 04, 2015   doi: 10.1002/arch.21250   open full text
    Lacey J. Jenson, Jeffrey R. Bloomquist.
    Archives of Insect Biochemistry and Physiology. July 16, 2015
    A neuronal morphological phenotype can be induced in cultured Spodoptera frugiperda insect cells (Sf21) by supplementing serum‐containing media with 20‐hydroxyecdysone (20‐HE) and/or insulin. In this study, the primary objectives were to determine any role of ion channels in mediating the morphological change in cells treated with 20‐HE and insulin, and whether serum was required to observe this effect. Results showed serum‐free media also induced growth of processes in Sf21 cells, but at a lower percentage than that found previously in cells bathed in serum‐containing media. Veratridine, a sodium channel activator, increased cell survival when applied in combination with 20‐HE to Sf21 cells, and the effect was blocked by tetrodotoxin (1 μM) a known sodium channel blocker. Cobalt, a calcium channel blocker, showed significant inhibition of cell process growth when applied in combination with both 20‐HE and 20‐HE plus veratridine. Cobalt also showed significant inhibition of cell process growth when applied in combination with insulin. Thus, some type of sodium channel, as well as a mechanism for transmembrane calcium ion movement, are apparently expressed in Sf21 cells and are involved in the differentiation process. These cell lines may be used in a wide variety of endeavors, including the screening of insecticides, as well as foster basic studies of neurodevelopment and ecdysone action.
    July 16, 2015   doi: 10.1002/arch.21249   open full text
    Natalia A. Kryukova, Ekaterina A. Chertkova, Alexandra D Semenova, Yuri I. Glazachev, Irina A. Slepneva, Victor V. Glupov.
    Archives of Insect Biochemistry and Physiology. June 19, 2015
    Ectoparasitoids inject venom into hemolymph during oviposition. We determined the influence of envenomation by the parasitoid, Habrobracon hebetor, on the hemocytes of its larval host, Galleria mellonella. An increase in both intracellular Са2+ content and phospholipase C activity of the host hemocytes was recorded during 2 days following envenomation by the parasitoid. The decreased hemocyte viability was detected 1, 2, and 24 h after the envenomation. Injecting of the crude venom (final protein concentration 3 μg/ml) into the G. mellonella larvae led to the reduced hemocyte adhesion. The larval envenomation caused a decrease in transmembrane potential of the hemocytes. These findings document the suppression of hemocytic immune effectors in the parasitized host larvae.
    June 19, 2015   doi: 10.1002/arch.21247   open full text
    Hatibe Ertürk Kara, Yusuf Turan, Aylin Er, Mesut Acar, Sabiha Tümay, Selma Sinan.
    Archives of Insect Biochemistry and Physiology. May 01, 2014
    The greater wax moth, Galleria mellonella, is one of the most ruinous pests of honeycomb in the world. Beta‐glucosidases are a type of digestive enzymes that hydrolytically catalyzes the beta‐glycosidic linkage of glycosides. Characterization of the beta‐glucosidase in G. mellonella could be a significant stage for a better comprehending of its role and establishing a safe and effective control procedure primarily against G. mellonella and also some other insect pests. Laboratory reared final instar stage larvae were randomly selected and homogenized for beta‐glucosidase activity assay and subsequent analysis. The enzyme was purified to apparent homogeneity by salting out with ammonium sulfate and using sepharose‐4B‐l‐tyrosine‐1‐naphthylamine hydrophobic interaction chromatography. The purification was 58‐fold with an overall enzyme yield of 29%. The molecular mass of the protein was estimated as ca. 42 kDa. The purified beta‐glucosidase was effectively active on para/ortho‐nitrophenyl‐beta‐d‐glucopyranosides (p‐/o‐NPG) with Km values of 0.37 and 1.9 mM and Vmax values of 625 and 189 U/mg, respectively. It also exhibits different levels of activity against para‐nitrophenyl‐β‐d‐fucopyranoside (p‐NPF), para/ortho‐nitrophenyl β‐d‐galactopyranosides (p‐/o‐NPGal) and p‐nitrophenyl 1‐thio‐β‐d‐glucopyranoside. The enzyme was competitively inhibited by beta‐gluconolactone and also was very tolerant to glucose against p‐NPG as substrate. The Ki and IC50 values of δ‐gluconolactone were determined as 0.021 and 0.08 mM while the enzyme was more tolerant to glucose inhibition with IC50 value of 213.13 mM for p‐NPG.
    May 01, 2014   doi: 10.1002/arch.21171   open full text
  • Contacting Is Essential For Oviposition Deterrence Of Rhodojaponin‐Iii In Spodoptera Litura.
    Xin Yi, Jinxiang Liu, Peidan Wang, Meiying Hu, Guohua Zhong.
    Archives of Insect Biochemistry and Physiology. April 29, 2014
    In Lepidoptera, choosing the right site for egg laying is particularly important, because the small larvae cannot forage for alternate host plants easily. Some secondary compounds of plants have the ability to deter oviposition behaviors of insects. Rhodojaponin‐III, a botanical compound, has been reported to have intense deterring‐oviposition activity against many insects, which have important implications for agricultural pest management. This study provided evidence for elucidating the perception mechanism underlying Rhodojaponin‐III as oviposition deterrent. In this study, the antennas of moths could not elicit notable electroantennogram responses to Rhodojaponin‐III, which suggested the Rhodojaponin‐III could not exert effects like those volatile compounds. The results of physiological experiments confirmed the Rhodojaponin‐III could produce the oviposition deterrence effect against moths without depending on antennas, while the physical contact was essential for perceiving the compound, which suggested that the sensilla on tarsus and ovipositor could be chemoreceptor for Rhodojaponin‐III. Therefore, these sensilla were investigated by scanning electron microscopy to explore their potential functions in detecting Rhodojaponin‐III. This study highlighted the contacting mechanism in deterring oviposition behaviors of moths by Rhodojaponin‐III and provided new insight for development of contact‐based pest management.
    April 29, 2014   doi: 10.1002/arch.21170   open full text
    Rui‐Rui Chen, Xiang‐Liang Ren, Zhao‐Jun Han, Li‐Li Mu, Guo‐Qing Li, Yan Ma, Jin‐Jie Cui.
    Archives of Insect Biochemistry and Physiology. April 24, 2014
    In S. exigua, ingestion of Cry1Ac reduces larval growth, shortens lifespan, and decreases copulation and oviposition of the adults. Cadherin‐like protein SeCad1b in S. exigua has recently been published. Here, we tested whether SeCad1b mediates the negative effects of Cry1Ac. We identified three potential Cry toxin binding regions in SeCad1b, i.e., 879EIAIQITDTNN889, 1357SLLTVTI1363, and 1436GVISLNFQ1443. We expressed and purified a truncated cadherin, rSeCad1bp, and its interspecific homologue, rHaBtRp, from H. armigera that contain the putative toxin binding regions. Using a toxin overlay assay, we found that rSeCad1bp specifically binds to biotinylated Cry1Ac in a dose‐dependent manner. We also discovered that an addition of rSeCad1bp and rHaBtRp enhances the suppression of larval growth by Cry1Ac, although rSeCad1bp is less suppressive than rHaBtRp. Finally, RNA interference‐mediated knockdown of SeCad1b reduced approximately 80% of the target gene and significantly alleviated the negative effect of CrylAc on larval growth. We infer that the  S. exigua SeCad1b is a functional receptor of Cry1Ac.
    April 24, 2014   doi: 10.1002/arch.21163   open full text
    Chiou Ling Chang, Scott Geib, Il Kyu Cho, Qing X. Li, David Stanley.
    Archives of Insect Biochemistry and Physiology. April 21, 2014
    Lufenuron (LFN), a chitin synthase inhibitor, impacts the fertility of Ceratitis capitata, Bactrocera dorsalis, B. cucurbitae, and B. latifrons. We posed the hypothesis that LFN curtails egg hatch in the solanaceous fruit fly, B. latifrons. In this study, newly emerged virgin adults were sexed and fed for 12 days with varying concentrations of LFN‐laced agar diets until sexual maturation. Eggs were collected from 12‐d‐old adults and the egg hatch was assessed. Egg hatch decreased in adults reared on LFN‐treated diets. LFN‐treated media did not influence fertility after one gender was reared on experimental and the other on control media before mating. Exposure to LFN‐treated medium after mating led to reduced egg hatch. We infer that LFN is not a permanent sterilant, and reduced egg hatch depends on continuous exposure to dietary LFN after mating. Proteomic analysis identified two differentially expressed proteins, a pheromone binding protein and a chitin binding protein, between adults maintained on LFN‐treated and control diets. Expression of two genes encoding chitin synthase 2, and chitin binding protein, was altered in adults exposed to dietary LFN. LFN treatments also led to increased expression of two odorant binding proteins one in females and one in males. We surmise these data support our hypothesis and provide insight into LFN actions.
    April 21, 2014   doi: 10.1002/arch.21169   open full text
    Xuehua Pan, Kai Lu, Shu Qi, Qiang Zhou, Qiang Zhou.
    Archives of Insect Biochemistry and Physiology. April 21, 2014
    Nitrogen availability from dietary protein has profound effects on the physiology and ecology of insect herbivores. The amount of amino acids consumed by Nilaparvata lugens impacts its phenotypic characteristics and reproduction. In this work, we hypothesized that amino acids deficiency leads to physiological trade‐offs between survival and reproduction. We investigated the effect of larval nutrition on larval period, wing dimorphism, egg production, ovarian development, lifespan, and stored nutrients. Larvae were reared on the standard medium and an amino acid deficient medium (AADM), adults were reared on the standard medium. Nymphs reared on AADM had shorter larval period (20.78 d/23.09 d), higher brachypterous forms (34.06%/16.52%), the adults females were fed back on standard medium after emergency, they featured extended preoviposition period (11.41/13.45 d), declining number of laid eggs (2.27/37.44), ovarian dysplasia, and shorter lifespan compared with control group. Adults from both dietary treatment groups had approximately the same proportion of total lipids and protein nutrients carried over from larvae feeding into adulthood. We infer that N. lugens makes a physiological trade‐off between survival and reproduction by suppressing ovarian development. This is probably a common strategy during times of nutritional deficiency in nature.
    April 21, 2014   doi: 10.1002/arch.21162   open full text
  • Triterpene Acids From Apple Peel Inhibit Lepidopteran Larval Midgut Lipases And Larval Growth.
    John T. Christeller, Tony K. McGhie, Joanne Poulton, Ngaire P. Markwick.
    Archives of Insect Biochemistry and Physiology. April 17, 2014
    Fruit extracts from apple, kiwifruit, feijoa, boysenberry, and blueberry were screened for the presence of lipase inhibitory compounds against lepidopteran larval midgut crude extracts. From 120 extracts, six showed significant inhibition with an extract from the peel of Malus × domestica cv. “Big Red” showing highest levels of inhibition. Because this sample was the only apple peel sample in the initial screen, a survey of peels from seven apple cultivars was undertaken and showed that, despite considerable variation, all had inhibitory activity. Successive solvent fractionation and LC‐MS of cv. “Big Red” apple peel extract identified triterpene acids as the most important inhibitory compounds, of which ursolic acid and oleanolic acid were the major components and oxo‐ and hydroxyl‐triterpene acids were minor components. When ursolic acid was incorporated into artificial diet and fed to Epiphyas postvittana Walker (Tortricidae: Lepidoptera) larvae at 0.16% w/v, a significant decrease in larval weight was observed after 21 days. This concentration of ursolic acid is less than half the concentration reported in the skin of some apple cultivars.
    April 17, 2014   doi: 10.1002/arch.21157   open full text
    Peng He, Jin Zhang, Zhao‐Qun Li, Ya‐Nan Zhang, Ke Yang, Shuang‐Lin Dong, Peng He.
    Archives of Insect Biochemistry and Physiology. April 17, 2014
    Odorant‐degrading esterases (ODEs) act in the fast deactivation of ester pheromone components and plant volatiles in insects. However, only few ODEs have been characterised to date. In this study, six full‐length putative ODE genes (designated SexiCXE4, 5, 17, 18, 20, and 31) were cloned from the male antennae of Spodoptera exigua. The deduced amino acid sequences possessed typical characteristics of a carboxylesterase (CXE) and shared high identities with reported insect CXEs. The tissue and temporal expression patterns were investigated by quantitative real time PCR. Although all six SexiCXEs are expressed in antennae of both sexes, SexiCXE4, 17 and 20 are antennae‐enriched; while SexiCXE5 and SexiCXE18 are dominantly expressed in wings, and SexiCXE31 is mainly expressed in proboscises, heads and legs. With the highly biased expression in antennae and proboscises, SexiCXE4 was selected for further functional assay. The recombinant SexiCXE4 were expressed in High‐five cells and purified by a Ni2+ affinity column. SexiCXE4 has much higher enzyme activity against plant volatiles (Z)‐3‐hexenyl acetate and hexyl acetate than to the sex pheromone components, suggesting that it may function mostly in the degradation of the plant volatiles.
    April 17, 2014   doi: 10.1002/arch.21164   open full text
    Yongan Tan, Liubin Xiao, Yang Sun, Jing Zhao, Lixin Bai, Yingfang Xiao.
    Archives of Insect Biochemistry and Physiology. April 16, 2014
    Trehalose, a major hemolymph sugar in insects, is hydrolyzed by trehalase. We identified a soluble and a membrane‐bound form of trehalase and isolated the corresponding mRNA, ALTre‐1, and ALTre‐2 in the cotton mirid bug, Apolygus lucorum. The deduced amino acid sequences of ALTre‐1 and ALTre‐2 revealed mature proteins with 643 and 617 amino acids, respectively. ALTre‐1 and ALTre‐2 contained trehalase signature motifs, and ALTre‐2 contained a putative transmembrane domain near the C‐terminus, suggesting that ALTre‐1 and ALTre‐2 encoded a soluble trehalase and a membrane‐bound trehalase, respectively. Comparison of trehalase activity at different developmental stages and in six tissues indicated that soluble trehalase activity accounted for the majority of total trehalase activity in A. lucorum. ALTre‐1 and ALTre‐2 were expressed in all tissues and stages, with the highest expression of both in the second instar nymphs, ALTre‐1 in the ovary and malpighian tubules, ALTre‐2 in the flight muscles and fat body. Following the exposure of second instar nymph to 20‐E, the soluble trehalase activity increased gradually while the membrane‐bound trehalase activity remained at its initial level. Similarly, 20‐E upregulated ALTre‐1 expression but had no effect on ALTre‐2 expression. These results suggest that an increase of this soluble trehalase activity was upregulated by ALTre‐1 gene.
    April 16, 2014   doi: 10.1002/arch.21166   open full text
    Meng‐Chen Tsai, Mei‐Er Chen, Cheng‐Lung Tsai.
    Archives of Insect Biochemistry and Physiology. April 16, 2014
    A Bactrocera dorsalis hexamerin (BdAr) cDNA was cloned (GenBank accession no. KF815528), and its transcriptional expression profiles were determined. The complete 2,530‐bp cDNA encodes a 780‐amino acid protein with a predicted molecular mass of 94.01 kDa. The proportions of phenylalanine (7.8%), tyrosine (11.2%), and methionine (2.6%) in BdAr as well as all other amino acids are reported. BdAr transcripts were detected in the brain, flight muscle, foregut, Malpighian tubules, and fat body. In the larval stage, BdAr transcripts were expressed in the early third instar and increased in the late third instar. In pupae, the highest expression of BdAr mRNA was present on day 1, then declined and persisted through day 2 to day 8. In adult females, the relative expression of BdAr was significantly higher on day 0 and day 1 compared to day 6 to day 10 while it was highest in newly eclosed adult males. The comparison of the BdAr expression between 8–10‐day‐old males and females showed a higher level in females. Our phylogenetic analysis results suggest to us that BdAr is similar to Drosophila larval serum protein 1γ.
    April 16, 2014   doi: 10.1002/arch.21167   open full text
    Khaleelulla Saheb Shaik, Yiwen Wang, L. Aravind, Bernard Moussian.
    Archives of Insect Biochemistry and Physiology. April 10, 2014
    The dopamine monoxygenase N‐terminal (DOMON) domain is found in extracellular proteins across several eukaryotic and prokaryotic taxa. It has been proposed that this domain binds to heme or sugar moieties. Here, we have analyzed the role of four highly conserved amino acids in the DOMON domain of the Drosophila melanogaster Knickkopf protein that is inserted into the apical plasma membrane and assists extracellular chitin organization. In principal, we generated Knickkopf versions with exchanged residues tryptophan299, methionine333, arginine401, or histidine437, and scored for the ability of the respective engineered protein to normalize the knickkopf mutant phenotype. Our results confirm the absolute necessity of tryptophan299, methionine333, and histidine437 for Knickkopf function and stability, the latter two being predicted to be critical for heme binding. In contrast, arginine401 is required for full efficiency of Knickkopf activity. Taken together, our genetic data support the prediction of these residues to mediate the function of Knickkopf during cuticle differentiation in insects. Hence, the DOMON domain is apparently an essential factor contributing to the construction of polysaccharide‐based extracellular matrices.
    April 10, 2014   doi: 10.1002/arch.21165   open full text
    Jinfeng Ni, Yan Wu, Chao Yun, Menglan Yu, Yulong Shen.
    Archives of Insect Biochemistry and Physiology. April 09, 2014
    Major β‐glucosidase (BG) and endo‐β‐1,4‐glucanase (EG) activities were localized to the midgut of the fungus‐growing termite Macrotermes barneyi. Previously, we obtained the endogenous BG gene (MbmgBG1) from the midgut of M. barneyi. Here, we report the cDNA cloning of another endogenous cellulase, the EG protein MbEG1. This cellulase was partially purified from crude extract of the midgut of worker termites using zymogram analysis. Based on the N‐terminal amino acid sequence and using rapid amplification of cDNA ends (RACE), a full‐length cDNA of 1,843 base pairs was obtained. This encoded 448 amino acids and the sequence was similar to that of the members of glycoside hydrolase family 9. The MbEG1 transcript was detected primarily in the midgut using quantitative real‐time polymerase chain reaction (PCR). To confirm functional activity of MbEG1, heterologous expression was conducted in both Escherichia coli and Pichia pastoris expression systems. Results indicated that MbEG1 could be functionally expressed in P. pastoris. This study provides the information that may facilitate understanding of cellulolytic systems in fungus‐growing termites.
    April 09, 2014   doi: 10.1002/arch.21158   open full text
    Jiqiao Fan, Pengfei Han, Xiurun Chen, Qionbo Hu, Mingqiang Ye.
    Archives of Insect Biochemistry and Physiology. April 09, 2014
    Destruxin A (DA), a cyclodepsipeptidic secondary metabolite of the entomopathogenic fungus, Metarhizium anisopliae, is an important anti‐immunity agent against insect hemocytes. To understand the mechanism of the molecular responses to DA, fifth‐instar larvae of the silkworm, Bombyx mori, were injected with 2 μg of DA. The proteomics of hemocytes were then investigated using two‐dimensional electrophoresis and mass spectrometry, and validated qPCR. As a result, a total of 47 differently expressed protein spots were detected and 22 proteins in 26 spots were identified. There are eight immunity‐related proteins, including three downregulated proteins (antitrypsin isoform 3, p50 protein, and calreticulin precursor) and five upregulated proteins (C‐type lectin 10 precursor, serine proteinase‐like protein, paralytic peptide, PPO‐1, and PPO‐2). Four resistance‐ and/or stress‐related proteins (arginine kinase, carboxylesterase clade H, member 1, aminoacylase, and thiol peroxiredoxin) were upregulated. Ten proteins with other or unknown functions were also recorded. Five selected proteins were verified with qPCR. These results provide new insights into the molecular mechanism of host immune response to DA challenge.
    April 09, 2014   doi: 10.1002/arch.21160   open full text
  • Influence Of Catalase Gene Silencing On The Survivability Of Sitobion Avenae.
    Fei Deng, Zhangwu Zhao.
    Archives of Insect Biochemistry and Physiology. April 09, 2014
    Reactive oxygen species (ROS), such as superoxide anions and hydrogen peroxide produced in cell metabolism, result in the disruption of cellular function and structure. Catalase (CAT), an enzyme which exists in almost all organisms including plants, invertebrates and vertebrates, acts in scavenging ROS. In this study, a sequence fragment encoding a CAT‐like protein from wheat aphids ( Sitobion avenae) was cloned. Amino acid sequence alignment showed this CAT shared relatively high conservation with CAT sequences from other insects. We detected cat mRNA levels at nymphs of different stages and adults and results showed that cat expression in adults was significantly higher compared to juvenile stages. At the third instar stage, ingestion of dsCAT significantly knocked down CAT expression. Continuous feeding of dsCAT mixed in an artificial diet led to reduced survival rate and ecdysis index. This study indicates that cat, a potential target gene for management of insect pests, is important for maintaining the survival of  S. avenae.
    April 09, 2014   doi: 10.1002/arch.21161   open full text
    Aneta Strachecka, Krzysztof Olszewski, Jerzy Paleolog, Grzegorz Borsuk, Milena Bajda, Magdalena Krauze, Malwina Merska, Jacek Chobotow.
    Archives of Insect Biochemistry and Physiology. March 21, 2014
    Natural bioactive preparations that will boost apian resistance, aid body detoxification, or fight crucial bee diseases are in demand. Therefore, we examined the influence of coenzyme Q10 (CoQ10, 2,3‐dimethoxy, 5‐methyl, 6‐decaprenyl benzoquinone) treatment on honeybee lifespan, Nosema resistance, the activity/concentration of antioxidants, proteases and protease inhibitors, and biomarkers. CoQ10 slows age‐related metabolic processes. Workers that consumed CoQ10 lived longer than untreated controls and were less infested with Nosema spp. Relative to controls, the CoQ10‐treated workers had higher protein concentrations that increased with age but then they decreased in older bees. CoQ10 treatments increased the activities of antioxidant enzymes (superoxide dismutase, GPx, catalase, glutathione S‐transferase), protease inhibitors, biomarkers (aspartate aminotransferase, alkaline phosphatase, alanine aminotransferase), the total antioxidant potential level, and concentrations of uric acid and creatinine. The activities of acidic, neutral, and alkaline proteases, and concentrations of albumin and urea were lower in the bees that were administered CoQ10. CoQ10 could be taken into consideration as a natural diet supplement in early spring before pollen sources become available in the temperate Central European climate. A response to CoQ10 administration that is similar to mammals supports our view that Apis mellifera is a model organism for biochemical gerontology.
    March 21, 2014   doi: 10.1002/arch.21159   open full text
    Jia Wang, Wen‐Bo He, Yun‐Lin Su, Xiao‐Li Bing, Shu‐Sheng Liu.
    Archives of Insect Biochemistry and Physiology. March 09, 2014
    Trehalases (Tres) have been demonstrated to be the key enzymes that are involved in various trehalose‐associated physiological processes in insects. However, little attention has been devoted to the Tres in the whitefly, Bemisia tabaci. In this study, a soluble Tre (BtTre‐1) and a membrane‐bound Tre (BtTre‐2) were cloned in the invasive cryptic species Middle East‐Asia Minor 1 (MEAM1) of the whitefly B. tabaci complex. Alignment of deduced amino acids sequences of both BtTres revealed that they share common consensus regions and residues with Tres of other insect species. Levels of BtTres expression in various stages and tissues of the whitefly suggested that BtTre‐2 may play a key role in trehalose catabolism during development of the whitefly, especially for oocyte development, while BtTre‐1 may prevent trehalose in salivary gland from leaking and entering into plants along with saliva. Potential roles of trehalose catabolism in response to direct and/or plant‐mediated indirect effects of Tomato Yellow Leaf Curl China Virus (TYLCCNV) were also detected. Whiteflies feeding on virus‐infected tobacco plants showed higher BtTres expressions and accordingly higher BtTres activity but lower trehalose content than those feeding on uninfected plants. The enhanced trehalose catabolism may be beneficial to oocyte development in ovary and attenuate plant defensive responses induced by trehalose in saliva. Viruliferous and nonviruliferous whiteflies feeding on cotton, a nonhost plant for TYLCCNV, differed significantly only in trehalose content. The higher trehalose content in viruliferous whiteflies may be conducive to resisting the stress inflicted by TYLCCNV.
    March 09, 2014   doi: 10.1002/arch.21155   open full text
    Mahboob Ghamari, Vahid Hosseininaveh, Ali Darvishzadeh, Nanasaheb P. Chougule.
    Archives of Insect Biochemistry and Physiology. March 07, 2014
    The spined soldier bug, Podisus maculiventris, is a generalist predator of insects and has been used in biological control. However, information on the digestion of food in this insect is lacking. Therefore, we have studied the digestive system in P. maculiventris, and further characterized carbohydrases in the digestive tract. The midgut of all developmental stages was composed of anterior, median, and posterior regions. The volumes of the anterior midgut decreased and the median midgut increased in older instars and adults, suggesting a more important role of the median midgut in food digestion. However, carbohydrase activities were predominant in the anterior midgut. In comparing the specific activity of carbohydrases, α‐amylase activity was more in the salivary glands (with two distinct activity bands in zymograms), and glucosidase and galactosidase activities were more in the midgut. Salivary α‐amylases were detected in the prey hemolymph, demonstrating the role of these enzymes in extra‐oral digestion. However, the catalytic efficiency of midgut α‐amylase activity was approximately twofold more than that of the salivary gland enzymes, and was more efficient in digesting soluble starch than glycogen. Midgut α‐amylases were developmentally regulated, as one isoform was found in first instar compared to three isoforms in fifth instar nymphs. Starvation significantly affected carbohydrase activities in the midgut, and acarbose inhibited α‐amylases from both the salivary glands and midgut in vitro and in vivo. The structural diversity and developmental regulation of carbohydrases in the digestive system of P. maculiventris demonstrate the importance of these enzymes in extra‐oral and intra‐tract digestion, and may explain the capability of the hemipteran to utilize diverse food sources.
    March 07, 2014   doi: 10.1002/arch.21153   open full text
    Qing‐Bo Tang, Ling‐Qiao Huang, Chen‐Zhu Wang, Qing‐Bo Tang, Huan Zhan, Joop J. A. Loon.
    Archives of Insect Biochemistry and Physiology. March 05, 2014
    The polyphagous cotton bollworm Helicoverpa armigera (Hübner) and the oligophagous oriental tobacco budworm Helicoverpa assulta (Guenée) (Lepidoptera: Noctuidae) display contrasting heritable feeding preferences for cotton and pepper leaves. In this study, electrophysiological response patterns to cotton and pepper leaf saps in gustatory sensilla styloconica on the maxillae of these two species, their reciprocal F1 hybrids, and backcrossed lines were investigated using the tip recording technique. The identity of the neurons responding to the two leaf saps has been established using action potential waveform analysis. The two plant leaf saps elicited neural activity in at least six of the eight taste neurons innervating the lateral and medial sensilla styloconica of the parental species and crosses. Discriminant analysis of this multineural input predicted that correct classification occurred in 87 – 92% of the cases. Differences in taste neuron responses between insect lines to the two plant saps were consistent with differences in feeding preference behaviors. Comparisons of taste neuron response patterns of parental species, F1 hybrids and backcrosses indicate that autosomal loci contributed to the difference in gustatory response patterns between the two Helicoverpa species with the H. armigera derived alleles being partly dominant to those carried by H. assulta. These findings contribute to the understanding of gustatory codes for preference and provide insight into taste evolution of lepidopteran insects.
    March 05, 2014   doi: 10.1002/arch.21154   open full text
    Jiyeong Park, Yonggyun Kim.
    Archives of Insect Biochemistry and Physiology. February 24, 2014
    Insect immunity is innate and highly efficient to defend against various pathogens. However, uncontrolled excessive immune responses would be highly detrimental and energy‐consuming processes. An insect cytokine, plasmatocyte‐spreading peptide (SePSP), induces hemocyte‐spreading behavior as well as activates phenoloxidase (PO) in the beet armyworm, Spodoptera exigua. A hemocyte transcriptome of S. exigua contains a partial sequence of a putative PSP‐binding protein (SePSP‐BP1). SePSP‐BP1 was expressed in most larval stages except in the last instar. However, a bacterial challenge induced SePSP‐BP1 expression in the last instar especially in hemocytes and fat body. Injecting a double‐stranded RNA specific to SePSP‐BP1 (dsPSP‐BP1) suppressed the induction of SePSP‐BP1 expression in response to bacterial challenge. The larvae treated with dsPSP‐BP1 suffered high mortality to infection of nonpathogenic bacteria due to uncontrolled high PO activity. SePSP significantly induced PO activity. The eicosanoid synthesis inhibitor, dexamethasone (DEX), inhibited SePSP‐mediated PO activation. However, treatment with prostaglandin E2 (PGE2) induced a transient increase of PO activity under DEX treatment. Treatment of dsPSP decreased the duration of PO activation induced by PGE2, while treatment of dsPSP‐BP1 increased the induced period. These results suggest that prostaglandin mediates PSP signals in both upregulation of PO activity and its subsequent downregulation via SePSP‐BP1.
    February 24, 2014   doi: 10.1002/arch.21156   open full text
  • Feeding On A Begomovirus‐Infected Plant Enhances Fecundity Via Increased Expression Of An Insulin‐Like Peptide In The Whitefly, Meam1.
    Jian‐Yang Guo, Lu Cheng, Gong‐Yin Ye, Qi Fang, Jian‐Yang Guo.
    Archives of Insect Biochemistry and Physiology. February 14, 2014
    The Middle East‐Minor 1 cryptic species (MEAM1), Bemisia tabaci (Gennadius) is a globally invasive pest. It spreads widely due to its high fecundity and mutualistic interactions with the virus they vector. Feeding on virus (tomato yellow leaf curl China virus, TYLCCNV)‐infected host plants improves their fecundity, however, the key factor regulating the signaling transduction in reproduction of whitefly remains to be identified. Here, we cloned a full length cDNA encoding an insulin‐like peptide in MEAM1 (BtILP1) and investigated its expression profile, functions, and the expression induced by feeding on virus‐infected tobacco plants. The full length cDNA of BtILP1 was 590 bps and encoded an open reading frame containing 149 amino acid residues. Multiple sequences alignment results showed BtILP1 contained the structural features typical of the insulin family. Expression dynamics associated with development showed the expression level of BtILP1 peaked at 5 days posteclosion (PE). During 1 to 3 days PE, BtILP1 was expressed highly in the head and abdomen of female adults and highly in the head during 5 to 7 days PE. Knockdown of the BtILP1 expression also impaired vitellogenin gene expression at both transcript and protein levels. Downregulating BtILP1 expression decreased fecundity of female adults and hatching rate of eggs. Feeding on virus‐infected tobacco increased BtILP1 expression in MEAM1 female adults. We infer feeding on begomovirus‐infected tobacco enhances the reproduction of MEAM1 by inducing BtILP1 expression. Our results give a new sight into the mutualistic interactions between virus and its insect vector.
    February 14, 2014   doi: 10.1002/arch.21151   open full text
    Lili Sun, Zhiying Wang, Chuanshan Zou, Chuanwang Cao.
    Archives of Insect Biochemistry and Physiology. February 01, 2014
    As the main group of detoxification enzymes, cytochrome P450 monoxygenases (P450s) catalyse an extremely diverse range of reactions that play an important role in the detoxification of foreign compounds. Transcription profiling of 12 Lymantria dispar P450 genes from the CYP6 subfamily believed to be involved in insecticide metabolism was performed in this study. Life‐stage transcription profiling of CYP6 genes revealed significant variations between eggs, larvae, pupae, and adult males and females. Exposure of larvae to sublethal doses of deltamethrin, omethoate, and carbaryl enhanced the transcription of most of the CYP6 P450 genes, with induction peaking between 24 and 72 h after exposure. Transcription profiles were dependent on the levels of insecticide exposure and the various developmental stages.
    February 01, 2014   doi: 10.1002/arch.21152   open full text
    Ariane A. Rocha, Carlos J. C. Pinto, Richard I. Samuels, Daniel Alexandre, Carlos P. Silva.
    Archives of Insect Biochemistry and Physiology. January 30, 2014
    The leaffooted bug, Leptoglossus zonatus (Hemiptera: Coreidae) is an emerging pest of several crops around the World and up to now very little is known of its digestive system. In this article, glycoside hydrolase (carbohydrase) activities in the adult midgut cells and in the luminal contents of L. zonatus adult females were studied. The results showed the distribution of digestive carbohydrases in adults of this heteropteran species in the different intestinal compartments. Determination of the spatial distribution of α‐glucosidase activity in L. zonatus midgut showed only one major molecular form, which was not equally distributed between soluble and membrane‐bound isoforms, being more abundant as a membrane‐bound enzyme. The majority of digestive carbohydrases were found in the soluble fractions. Activities against starch, maltose and the synthetic substrate NPαGlu were found to show the highest levels of activity, followed by enzymes active against galactosyl oligosaccharides. Based on ion‐exchange chromatography elution profiles and banding patterns in mildly denaturing electrophoresis, both midgut α‐amylases and α‐galactosidases showed at least two isoforms. The data suggested that the majority of carbohydrases involved in initial digestion were present in the midgut lumen, whereas final digestion of starch and of galactosyl oligosaccharides takes place partially within the lumen and partially at the cell surface. The complex of carbohydrases here described was qualitatively appropriate for the digestion of free oligosaccharides and oligomaltodextrins released by α‐amylases acting on maize seed starch granules.
    January 30, 2014   doi: 10.1002/arch.21149   open full text
    Guo Xia Liu, Ning Xuan, Dong Chu, Hong Yan Xie, Zhong Xue Fan, Yu Ping Bi, Jean‐François Picimbon, Yu Chuan Qin, Su Ting Zhong, Yao Fa Li, Zhan Lin Gao, Wen Liang Pan, Guo Ying Wang, Balaji Rajashekar.
    Archives of Insect Biochemistry and Physiology. January 29, 2014
    Chemosensory proteins (CSPs) are a group of small soluble proteins found so far exclusively in arthropod species. These proteins act in chemical communication and perception. In this study, a gene encoding the Type 1 CSP (BtabCSP1) from the agricultural pest Bemisia tabaci (whitefly) was analyzed to understand sequence variation and expression specificity in different biotypes. Sequence analysis of BtabCSP1 showed significant differences between the two genetically characterized biotypes, B and Q. The B‐biotype had a larger number of BtabCSP1 mutations than the Q‐biotype. Similar to most other CSPs, BtabCSP1 was more expressed in the head than in the rest of the body. One‐step RT‐PCR and qPCR analysis on total messenger RNA showed that biotype‐Q had higher BtabCSP1 expression levels than biotype‐B. Females from a mixed field‐population had high levels of BtabCSP1 expression. The interaction of BtabCSP1 with the insecticide thiamethoxam was investigated by analyzing the BtabCSP1 expression levels following exposure to the neonicotinoid, thiamethoxam, in a time/dose‐response study. Insecticide exposure increased BtabCSP1 expression (up to tenfold) at 4 and 24 h following 50 or 100 g/ml treatments.
    January 29, 2014   doi: 10.1002/arch.21148   open full text
    Zhiqian Li, Jianhao Jiang, Yazhou Chen, Lang You, Yongping Huang, Anjiang Tan, Zhiqian Li, Jianhao Jiang, Baolong Niu, Zhiqi Meng.
    Archives of Insect Biochemistry and Physiology. January 29, 2014
    The PAR‐domain protein 1 (PDP1) is essential for locomotor activity of insects. However, its functions in insect growth and development have not been studied extensively, which prompted our hypothesis that PDP1 acts in energy metabolism. Here we report identification of TcPDP1 in the red flour beetle, Tribolium castaneum, and its functional analysis by RNAi. Treating larvae with dsTcPDP1 induced pupae developmental arrestment, accompanied by accelerated fat body degradation. dsTcPDP1 treatments in adults resulted in reduced female fecundity. Disruption of TcPDP1 expression affected the transcription of genes involved in insulin signaling transduction and mechanistic target of rapamycin (mTOR) pathway. These results support our hypothesis that TcPDP1 acts in energy metabolism in T. castaneum.
    January 29, 2014   doi: 10.1002/arch.21146   open full text
    Lina Zhao, Ping Wei, Hongshuang Guo, Shigui Wang, Bin Tang.
    Archives of Insect Biochemistry and Physiology. January 26, 2014
    Forkhead (Fox) transcription factors display functional diversity and are involved in various metabolic and developmental processes. The Spodoptera exigua Fox (SeFox) encodes a protein of 353 amino acids with a theoretical molecular mass of approximately 38.99 kDa and an isoelectric point of 8.86. qPCR results revealed that SeFox was expressed mainly in the brain, fat body, epidermis, midgut, Malpighian tubules, and testis. SeFox was expressed, with some changes, throughout development in the fat body and whole body. Injection of dsSeFox (SeFox dsRNA) into larvae resulted in incidences of albino plus molting deformity (4.8%), molting deformity (26.2%), and albino phenotypes (69.1%). dsSeFox injection resulted in approximately 50% knockdown of transcript levels at 36 h. Compared with control groups, hexokinase (HK) expression was reduced to approximately 40% at 48 h postinjection. Chitin synthase A (CHSA) expression was reduced to two‐thirds at 24 h, but increased at 72 h. Compared with untreated control and green fluorescent protein‐treated groups, Chitin synthase B (CHSB) expression decreased to 33% following dsSeFox injection by 36 h. We infer from our results that forkhead transcription factors act in chitin synthesis in S. exigua.
    January 26, 2014   doi: 10.1002/arch.21145   open full text
    Ann Sandhya Micheal, Muthangi Veera Venkata Subramanyam.
    Archives of Insect Biochemistry and Physiology. November 12, 2013
    In this study, larvae of silkworm Bombyx mori were subjected to low temperature, hypoxia, and viral infection to evaluate stressor‐mediated oxidative stress (OS) and the induction of antioxidant enzymes (AOEs). Exposure to cold, hypoxia, and nuclear polyhedral virus for 24 h resulted in a significant increase in hydrogen peroxide generation with concomitant increase in lipid peroxidation (LPO) and protein carbonyl levels in midgut and hemocytes. AOEs such as superoxide dismutase and catalase also increased significantly in both the tissues and the increased AOEs reverted to control values during recovery. Ontogenic stages of the larvae showed a diminishing ability of the tissues to overcome OS induced by the stressors. A significant increase in AOE activity during short stress period indicated a possible transitory defense mechanism to avoid OS‐induced cell damage.
    November 12, 2013   doi: 10.1002/arch.21138   open full text
    Jianjun Mao, Changyan Liu, Fanrong Zeng.
    Archives of Insect Biochemistry and Physiology. November 12, 2013
    Aphid, a short germband insect, displays an embryogenesis different from that of long germband insect species. Furthermore, the development of its parthenogenetic and viviparous embryo is different from that of the embryo resulting from sexual reproduction. To better understand the genetic regulation of this type of embryogenesis, the functions of hunchback in asexual Acyrthosiphon pisum were investigated by parental RNAi. Microinjection of Aphb double‐stranded RNA yielded several defective phenotypes. Quantitative real‐time PCR analysis revealed that these defects resulted from reduction of Aphb mRNA level in injected aphids. All these results suggested that the hb gene in parthenogenetic and viviparous Acyrthosiphon pisum was involved in abdominal identity suppression and germband growth as its homologue does in sexual insects.
    November 12, 2013   doi: 10.1002/arch.21137   open full text
    Amit Sethi, Elena S. Kovaleva, Jeffrey M. Slack, Susan Brown, George W. Buchman, Michael E. Scharf.
    Archives of Insect Biochemistry and Physiology. November 01, 2013
    Termites and their gut microbial symbionts efficiently degrade lignocellulose into fermentable monosaccharides. This study examined three glycosyl hydrolase family 7 (GHF7) cellulases from protist symbionts of the termite Reticulitermes flavipes. We tested the hypotheses that three GHF7 cellulases (GHF7‐3, GHF7‐5, and GHF7‐6) can function synergistically with three host digestive enzymes and a fungal cellulase preparation. Full‐length cDNA sequences of the three GHF7s were assembled and their protist origins confirmed through a combination of quantitative PCR and cellobiohydrolase (CBH) activity assays. Recombinant versions of the three GHF7s were generated using a baculovirus‐insect expression system and their activity toward several model substrates compared with and without metallic cofactors. GHF7‐3 was the most active of the three cellulases; it exhibited a combination of CBH, endoglucanase (EGase), and β‐glucosidase activities that were optimal around pH 7 and 30°C, and enhanced by calcium chloride and zinc sulfate. Lignocellulose saccharification assays were then done using various combinations of the three GHF7s along with a host EGase (Cell‐1), beta‐glucosidase (β‐glu), and laccase (LacA). GHF7‐3 was the only GHF7 to enhance glucose release by Cell‐1 and β‐glu. Finally, GHF7‐3, Cell‐1, and β‐glu were individually tested with a commercial fungal cellulase preparation in lignocellulose saccharification assays, but only β‐glu appreciably enhanced glucose release. Our hypothesis that protist GHF7 cellulases are capable of synergistic interactions with host termite digestive enzymes is supported only in the case of GHF7‐3. These findings suggest that not all protist cellulases will enhance saccharification by cocktails of other termite or fungal lignocellulases.
    November 01, 2013   doi: 10.1002/arch.21135   open full text
    Xiaoyi Zhang, Kai Lu, Qiang Zhou.
    Archives of Insect Biochemistry and Physiology. October 16, 2013
    As a member of the RNase III nucleases family, Dicer1 (Dcr1) protein plays an essential role in the production of microRNAs (miRNAs) and oocyte development. Here, the full‐length cDNA of Nilaparvata lugens Dcr1 (NlDcr1) was firstly cloned and analyzed, and then the function of NlDcr1 gene was investigated by RNAi. The open reading frameof NlDcr1 cDNA was 6,720 bp in length (GenBank Accession no. JX644040), which encoded for a protein of 2,239 amino acids. The NlDcr1 transcripts were present in all developmental stages and tissues investigated. The lowest levels of NlDcr1 expression were found in the first and second instar stage, while the highest in 7‐ and 9 ‐day‐old female adults. The expression levels were relatively higher in fat body, ovary, and midgut. After injecting 100 ng dsRNA of NlDcr1 into female adult, mRNA level of NlDcr1 gene was depleted significantly, and 10 kinds of tested miRNAs levels were downregulated in both whole body and ovary. The oocytes of females treated with dsNlDcr1 were smaller and badly malformed, among which the follicular cell did not develop normally, with unclear boundary between cells. These results suggest that NlDcr1 was crucial for the regulation of oogenesis in telotrophic ovary.
    October 16, 2013   doi: 10.1002/arch.21136   open full text
    Oleksandr V. Lozinsky, Oleh V. Lushchak, Volodymyr I. Lushchak.
    Archives of Insect Biochemistry and Physiology. October 07, 2013
    The toxicity of potassium ferrocyanide (PFC) and protective effects of 2,4‐dinitrophenol (DNP) under PFC treatment were tested on the Drosophila melanogaster model system. Fly larvae were raised on food supplemented with PFC at concentrations of 1.0 mM and mixtures with DNP in concentrations of 0.50 and 1.25 mM, either alone or in combination with 1.0 mM PFC. Food supplementation with PFC decreased larvae viability or pupation height, whereas when larvae were fed by PFC and DNP combination the decrease was less pronounced. Larval exposure to PFC and mixtures of DNP and PFC lowered activities of aconitase. Larval treatment with PFC resulted in higher carbonyl protein, uric acid, and low molecular mass thiols content and higher activity of thioredoxin reductase in adult flies, while DNP in mixtures with PFC relieved these effects. Furthermore, treatment with PFC/DNP mixtures resulted in higher activities of superoxide dismutase and glutathione‐S‐transferase. It is proposed that PFC toxicity is mainly related to the cyanide and iron ions, released during its decomposition. The potential mechanisms of protective DNP effects against PFC toxicity are discussed.
    October 07, 2013   doi: 10.1002/arch.21134   open full text
    Xiaoqian Chu, Wenjing Lu, Yuanying Zhang, Xingqi Guo, Rujiang Sun, Baohua Xu.
    Archives of Insect Biochemistry and Physiology. October 02, 2013
    Cuticular proteins (CPs) are key components of insect cuticle, a structure that plays a pivotal role in insect development and defense. In this study, we cloned the full‐length cDNA of a CP gene from Apis cerana cerana (AccCPR24). An amino acid sequence alignment indicated that AccCPR24 contains the conserved Rebers and Riddiford consensus sequence and shares high similarity with the genes from other hymenopteran insects. We then isolated the genomic DNA and found that the first intron, which is present in other CP genes, is absent in AccCPR24. Real‐time quantitative polymerase chain reaction (qPCR) analysis revealed that AccCPR24 is highly expressed in the late pupal stage and midgut. Expression was inhibited by an exogenous ecdysteroid in vitro but was enhanced by this hormone in vivo; environmental stressors, such as heavy metals and pesticides, also influenced gene expression. In addition, a disc diffusion assay showed that AccCPR24 enhanced the ability of bacterial cells to resist multiple stresses. We infer from our results that AccCPR24 acts in honeybee development and in protecting these insects from abiotic stresses.
    October 02, 2013   doi: 10.1002/arch.21132   open full text
    Katia C. Gondim, James E. Pennington, José Roberto Meyer‐Fernandes, Michele Alves‐Bezerra, Michael A. Wells.
    Archives of Insect Biochemistry and Physiology. September 30, 2013
    Lipophorin (Lp) is a major insect lipoprotein and is responsible for lipid transport between organs. In this study, the effect of starvation on Lp properties was analyzed in larval Manduca sexta during the fifth instar. Lp hemolymph concentrations in larvae at days 1 and 2 were around 2–3 mg/ml and at day 3 it increased to 8 mg/ml. When larvae were starved for 24 h, they did not grow, but their body mass and hemolymph volume did not decrease significantly. Differences in Lp densities were observed. In fed larvae, from days 1 to 4, two major Lp populations were found with densities of 1.124 ± 0.002 (high density Lp‐larval1, HDLp‐L1) and 1.141 ± 0.002 g/ml (HDLp‐L2). When larvae were starved for 24 h, only one Lp population was present, with density 1.114 ± 0.001 g/ml (HDLp‐Ls). When larvae were abdominally ligated at day 1 or 2 of fifth instar, only HDLp‐Ls was found after 24 h, indicating that the formation of this HDLp population was not dependent on any factor released by head. On the other hand, larvae that were ligated at day 3 showed the same Lp populations as the fed ones. In 24‐h starved larvae, lipid load in Lp was higher as compared to the fed controls. In 24‐h ligated larvae Lp lipid content increased when ligation was performed on day 1 or 2, but not on day 3. So, different responses to starvation can be observed depending on the developmental phase of the same larval instar.
    September 30, 2013   doi: 10.1002/arch.21133   open full text
    Jie Cao, Lei Shi, Yongzhi Zhou, Xiao Gao, Houshuang Zhang, Haiyan Gong, Jinlin Zhou.
    Archives of Insect Biochemistry and Physiology. September 16, 2013
    A new Kunitz‐type serine protease inhibitor, Rhipilin‐2, was identified in the tick Rhipicephalus hemaphysaloides. The cDNA sequence of Rhipilin‐2 is 693 bp, and it encodes a deduced 195 amino acid protein with a size of 22 kDa. Bioinformatic analysis shows that Rhipilin‐2 belongs to the Kunitz‐type family of inhibitors, containing one Kunitz domain with homology to the tissue factor pathway inhibitor. Using Real time polymerase chain reaction (Real time‐PCR), Rhipilin‐2 mRNA transcripts were detected in tick salivary glands and midgut. Blood feeding induced transcript expression. The recombinant protein was expressed in insect Sf9 cells and confirmed by immunofluorescence test and Western blot analysis with an anti‐His antibody. The purified recombinant Rhipilin‐2 inhibited serine protease trypsin and elastase, but not thrombin. The anticoagulant activity of Rhipilin‐2 was shown by delaying normal clotting of rabbit plasma in the activated partial thromboplastin time tests. These results indicate that Rhipilin‐2 is a novel Kunitz‐type serine protease inhibitor involved in tick blood feeding.
    September 16, 2013   doi: 10.1002/arch.21118   open full text
    Xiaoguang Liu, Yifan Zhang, Zijing Zhou, Zhangwu Zhao, Xiaoguang Liu.
    Archives of Insect Biochemistry and Physiology. September 16, 2013
    Neuropeptide F (NPF), the invertebrate homolog of neuropeptide Y (NPY) in vertebrates, shares similarity of structure and function with NPY. However, a few NPYs were also found in some insect species. In this paper, two neuropeptide genes encoding a NPF and a NPY were cloned from a tobacco budworm Helicoverpa assulta cDNA library. The npf1 gene further produces two splicing variants of rnRNAs, i.e. npf1a (lacks the 120 bp segment) and npf1b (includes a 120 bp segment). These two splicing variants form two mature peptides, NPF1a and NPF1b by modification of transcripts. NPF and NPY co‐exist in H. assulta.
    September 16, 2013   doi: 10.1002/arch.21119   open full text
    Hua‐jun Yang, Hu‐hu Xin, Yan Lu, Zi‐zheng Cai, Mei‐xian Wang, Rui‐ting Chen, Shuang Liang, Chabungbam Orville Singh, Jong‐nam Kim, Yun‐gen Miao.
    Archives of Insect Biochemistry and Physiology. August 26, 2013
    Molting in insects is regulated by molting hormones (ecdysteroids), which are also crucial to insect growth, development, and reproduction etc. The decreased ecdysteroid in titre results from enhanced ecdysteroid inactivation reactions including the formation of 3‐epiecdyson under ecdysone oxidase and 3‐dehydroecdysone 3α‐reductase (3DE 3α‐reductase). In this paper, we cloned and characterized 3‐dehydroecdysone 3α‐reductase (3DE 3α‐reductase) in different tissues and developing stage of the silkworm, Bombyx mori L. The B. mori 3DE 3α‐reductase cDNA contains an ORF 783 bp and the deduced protein sequence containing 260 amino acid residues. Analysis showed the deduced 3DE 3α‐reductase belongs to SDR family, which has the NAD(P)‐binding domain. Using the Escherichia coli, a high level expression of a fusion polypeptide band of approx. 33 kDa was observed. High transcription of 3DE 3α‐reductase was mainly presented in the midgut and hemolymph in the third day of fifth instar larvae in silkworm. The expression of 3DE 3α‐reductase at different stages of larval showed that the activity in the early instar was high, and then reduced in late instar. This is parallel to the changes of molting hormone titer in larval. 3DE 3α‐reductase is key enzyme in inactivation path of ecdysteroid. The data elucidate the regulation of 3DE 3α‐reductase in ecdyteroid titer of its targeting organs and the relationship between the enzyme and metamorphosis.
    August 26, 2013   doi: 10.1002/arch.21115   open full text
    Raymond V. Barbehenn, Joseph Kochmanski, Brandon Menachem, Lisa M. Poirier.
    Archives of Insect Biochemistry and Physiology. August 26, 2013
    Sulfur amino acids [cysteine (Cys) and methionine (Met)] play two major roles during animal development: protein synthesis for growth and glutathione synthesis for defense. For caterpillars, the levels of sulfur amino acids found in foliar protein can be especially low relative to their nutritional needs. Previous work has measured concentrations of glutathione (GSH; containing Cys) in specific animal tissues, but has not examined whole‐body levels to ascertain the costliness of this defense in terms of Cys allocation. This study examined whether the production of GSH varies between species and within individuals in accordance with an insect's need for antioxidant defense. Secondly, we quantified the allocation of total Cys (peptide‐bound plus free Cys) to GSH in caterpillars as an estimate of its cost. Two contrasting species were compared: Lymantria dispar (Lymantriidae), a species that is highly defended, and Malacosoma disstria (Lasiocampidae), a species that is less defended. As expected, GSH levels were significantly higher in L. dispar than in M. disstria. Consistent with the function of the midgut as a first line of defense against ingested toxins, GSH levels were significantly higher in these tissues than in the whole bodies of both species. A major finding in this study was that a large fraction of total Cys is used to produce GSH: GSH in the midguts of L. dispar and M. disstria contained 23 and 21%, respectively, of the total Cys in these tissues, and the GSH in their remaining body tissues contained 19 and 17% of the total Cys in these tissues. Levels of total Cys in caterpillar tissues followed the same pattern of distribution as did GSH, producing a strong association between GSH and total Cys (R2 = 0.794). We conclude that GSH is a costly defense, especially in generalist tree‐feeding species such as L. dispar. These results further suggest that the large allocation of Cys to GSH in highly defended species might produce a tradeoff by limiting the amount of Cys available for rapid growth.
    August 26, 2013   doi: 10.1002/arch.21116   open full text
  • Characterization Of Atg8 In Lepidopteran Insect Cells.
    Zhongchao Gai, Xiaojuan Zhang, Mayira Islam, Xia Wang, Aiying Li, Yongbo Yang, Yi Li, Jianxin Peng, Huazhu Hong, Kaiyu Liu.
    Archives of Insect Biochemistry and Physiology. August 19, 2013
    Yeast Atg8 and mammalian microtubule‐associated protein light chain 3 (LC3) are landmark proteins essential for autophagy. Here the lepidopteran Atg8, a homolog of LC3, is characterized. Sequence analysis reveals that Atg8 proteins are highly conserved in lepidopteran species. The abundance of endogeous Atg8 and the ratios of Atg8 conjugation to phosphatidylethanolamine (Atg8‐PE)/Atg8 are different among several lepidopteran cell lines and different tissues of Helicoverpa armigera larvae. Both the density of fluorescent pre‐autophagosomal structures with GFP‐Ha Atg8 and the abundance of Atg6 are positively correlated with levels of Atg8‐PE in different cell lines. The mutant GFP‐Atg8G116A has lost the function in punctual formation, suggesting that G116 is important for autophagy. Exogenous factors have significant influences on the conversion of Atg8 in lepidopteran cells. Bacillus thuringiensis enhances the degradation of Atg8 in Spodoptera litura Sl‐HP cells. Atg8‐PE degrades gradually with extension of amino acid starvation, and bafilomycin A1 can block the decrease through the inhibition of autophagosome fusion with lysosome. Interestingly, high pH is more effective than amino acid starvation in Bombyx mori Bme cells to induce the conversion of BmAtg8 to BmAgt8‐PE. Change of the quality of fetal bovine serum in the culture medium results in alteration of the ratio of Atg8‐PE/Atg8 in some lepidopteran cell lines.
    August 19, 2013   doi: 10.1002/arch.21114   open full text
  • Use Of Primary Cultures Of Kenyon Cells From Bumblebee Brains To Assess Pesticide Side Effects.
    Daniel E. Wilson, Rodrigo A. Velarde, Susan E. Fahrbach, Veerle Mommaerts, Guy Smagghe.
    Archives of Insect Biochemistry and Physiology. August 06, 2013
    Bumblebees are important pollinators in natural and agricultural ecosystems. The latter results in the frequent exposure of bumblebees to pesticides. We report here on a new bioassay that uses primary cultures of neurons derived from adult bumblebee workers to evaluate possible side‐effects of the neonicotinoid pesticide imidacloprid. Mushroom bodies (MBs) from the brains of bumblebee workers were dissected and dissociated to produce cultures of Kenyon cells (KCs). Cultured KCs typically extend branched, dendrite‐like processes called neurites, with substantial growth evident 24–48 h after culture initiation. Exposure of cultured KCs obtained from newly eclosed adult workers to 2.5 parts per billion (ppb) imidacloprid, an environmentally relevant concentration of pesticide, did not have a detectable effect on neurite outgrowth. By contrast, in cultures prepared from newly eclosed adult bumblebees, inhibitory effects of imidacloprid were evident when the medium contained 25 ppb imidacloprid, and no growth was observed at 2,500 ppb. The KCs of older workers (13‐day‐old nurses and foragers) appeared to be more sensitive to imidacloprid than newly eclosed adults, as strong effects on KCs obtained from older nurses and foragers were also evident at 2.5 ppb imidacloprid. In conclusion, primary cultures using KCs of bumblebee worker brains offer a tool to assess sublethal effects of neurotoxic pesticides in vitro. Such studies also have the potential to contribute to the understanding of mechanisms of plasticity in the adult bumblebee brain.
    August 06, 2013   doi: 10.1002/arch.21112   open full text
    Hongbiao Weng, Weifeng Shen, Yan Liu, Lihua He, Baolong Niu, Zhiqi Meng, Jianjun Mu.
    Archives of Insect Biochemistry and Physiology. August 06, 2013
    The ecdysone receptor (EcR) is the hormonal receptor of ecdysteroids, which regulates insect growth and development. In this study, we cloned and characterized two isoforms of EcR in Monochamus alternates named MaEcR A and MaEcR B. The cDNAs of MaEcR A and MaEcR B have open repeating frames of 1,695 and 1,392 bp, respectively. The deduced proteins have the same C‐terminal sequence and varied in N‐terminal, and are consistent with reports on other insect species, particularly with the receptor of another coleopteran, Tribolium castaneum. The isoform‐specific developmental expression profile of EcR in the epidermis and the midgut were analyzed with quantitative real‐time reverse‐transcriptase polymerase chain reaction in the pupal stage. RNA interference (RNAi) with common or isoform‐specific regions induced developmental stagnation. When treated in the later larval stage, RNAi with either the common sequence or an EcR A specific sequence caused more severe effects and most larvae died prior to adulthood. The EcR B specific sequence caused less severe effects and about half of the treated larvae became adults, but some showed developmental defects. RNAi with both isoforms at early pupal stage attenuated the expression of 20E‐regulated genes E74, E75, and HR3. The study demonstrates the role of EcR in the transduction of ecdysteroid response in Monochamus alternatus.
    August 06, 2013   doi: 10.1002/arch.21111   open full text
    Hongxia Liu, Wenmei Zhao, Meihong Yang, Jinlong Liu, Jintong Zhang.
    Archives of Insect Biochemistry and Physiology. August 06, 2013
    The adult behavior and sex pheromone titers of Isoceras sibirica Alpheraky (Lepidoptera, Cossidae) were investigated to determine the diel periodicity of pheromone production during one scotophase and the effect of age on pheromone production. The results showed that females began to call on the first night after eclosion and called mainly during the second half of scotophase. The percentage of females calling was highest in 1‐ to 3‐day‐old females and lowest in 4‐ to 5‐day‐old females. The onset of scotophase calling occurred earlier as females aged. The responses to the pheromone source of males aged 1–5 days were monitored in a wind tunnel. Peak activity was observed in 3‐day‐old males, 4 h after the onset of the scotophase. The mating of all 1‐ to 3‐day‐old moths began after 6 h in scotophase and some 4‐ to 5‐day‐old moths began during the fourth hour. The average duration of copulation was 34.2 ± 18.2 min (N = 45) and ranged from 17.0 to 56.3 min. Gas chromatography–mass spectrometry (GC–MS) analysis of hexane extracts of pheromone glands revealed that the titers of the three sex pheromone components, (Z)‐9‐tetradecenyl acetate (Z9–14:Ac), (Z)‐7‐tetradecenyl acetate, and (Z)‐9‐hexadecadecenyl acetate were very low on the first night after eclosion, increased and peaked on the second night, then decreased with age. During the first 4 h of the scotophase, titers remained invariant, whereas from 4 to 6 h, pheromone titers increased sharply and peaked, with the greatest peak observed in the primary component, Z9–14:Ac. After the peak, all recorded titers declined until they reached a minimum between the ninth and tenth hours of the dark cycle. In field tests, most of the males were captured in traps during 00:00–02:00 h (13 ± 0.48), and females aged 2 days attracted more males than females of other ages. We infer that the I. sibirica mating system is organized around circadian control of mate calling and mating.
    August 06, 2013   doi: 10.1002/arch.21109   open full text
    Salvador Hernández‐Martínez, Didier Barradas‐Bautista, Mario H. Rodríguez.
    Archives of Insect Biochemistry and Physiology. June 24, 2013
    The induction of DNA synthesis in various tissues of Anopheles albimanus, in response to challenge with Saccharomyces cerevisiae, Micrococcus luteus, and Serratia marcescens, was analyzed by 5‐bromo‐2‐deoxy‐uridine (BrdU) incorporation. Microorganism‐inoculated mosquitoes were fed with a sucrose solution containing BrdU and maintained alive for 5 days. Alternatively, abdominal carcasses of microorganisms‐inoculated mosquitoes were cultivated in Roswell Park Memorial Institute (RPMI) medium supplemented with BrdU for 5 days. Control groups were inoculated with RPMI alone. In both experiments, DNA synthesis, evidenced by epifluorescence with an anti‐BrdU fluorescein‐labeled antibody, occurred in fat body, epithelial cells of pleural membranes, dorsal vessel, and the oviducts. Relative quantification of DNA synthesis, evaluated by ELISA using an anti‐BrdU peroxidase‐labeled antibody, was higher in abdomen tissues of microorganisms‐inoculated mosquitoes than controls in in vitro and in vivo experiments. The intensity of DNA synthesis varied among the different microorganism challenges, but was higher in in vivo experiments, compared to cultured samples. These differences in DNA synthesis suggest a compartmentalization of the immune response, probably mediated by different signaling pathways.
    June 24, 2013   doi: 10.1002/arch.21108   open full text
  • Hormonal and nutritional regulation of insect fat body development and function.
    Ying Liu, Hanhan Liu, Shumin Liu, Sheng Wang, Rong‐Jing Jiang, Sheng Li.
    Archives of Insect Biochemistry and Physiology. February 03, 2009
    The insect fat body is an organ analogue to vertebrate adipose tissue and liver and functions as a major organ for nutrient storage and energy metabolism. Similar to other larval organs, fat body undergoes a developmental “remodeling” process during the period of insect metamorphosis, with the massive destruction of obsolete larval tissues by programmed cell death and the simultaneous growth and differentiation of adult tissues from small clusters of progenitor cells. Genetic ablation of Drosophila fat body cells during larval‐pupal transition results in lethality at the late pupal stage and changes sizes of other larval organs indicating that fat body is the center for pupal development and adult formation. Fat body development and function are largely regulated by several hormonal (i.e. insulin and ecdysteroids) and nutritional signals, including oncogenes and tumor suppressors in these pathways. Combining silkworm physiology with fruitfly genetics might provide a valuable system to understand the mystery of hormonal regulation of insect fat body development and function. © 2009 Wiley Periodicals, Inc.
    February 03, 2009   doi: 10.1002/arch.20291   open full text