1
|
You S, Yao S, Chen X, Hou Q, Liu Z, Lei G, Xie X, Liang Z, Yuchi Z, You M, Liu Y, Xiong L. CRISPR/Cas9-Mediated Knockout of the PxJHBP Gene Resulted in Increased Susceptibility to Bt Cry1Ac Protoxin and Reduced Lifespan and Spawning Rates in Plutella xylostella. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:8180-8188. [PMID: 38556749 DOI: 10.1021/acs.jafc.3c08721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/02/2024]
Abstract
Juvenile hormone binding protein (JHBP) is a key regulator of JH signaling, and crosstalk between JH and 20-hydroxyecdysone (20E) can activate and fine-tune the mitogen-activated protein kinase cascade, leading to resistance to insecticidal proteins from Bacillis thuringiensis (Bt). However, the involvement of JHBP in the Bt Cry1Ac resistance of Plutella xylostella remains unclear. Here, we cloned a full-length cDNA encoding JHBP, and quantitative real-time PCR (qPCR) analysis showed that the expression of the PxJHBP gene in the midgut of the Cry1Ac-susceptible strain was significantly higher than that of the Cry1Ac-resistant strain. Furthermore, CRISPR/Cas9-mediated knockout of the PxJHBP gene significantly increased Cry1Ac susceptibility, resulting in a significantly shorter lifespan and reduced fertility. These results demonstrate that PxJHBP plays a critical role in the resistance to Cry1Ac protoxin and in the regulation of physiological metabolic processes associated with reproduction in adult females, providing valuable insights to improve management strategies of P. xylostella.
Collapse
Affiliation(s)
- Shijun You
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Joint International Research Laboratory of Ecological Pest Control, Ministry of Education, Fuzhou 350002, China
| | - Shuyuan Yao
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Joint International Research Laboratory of Ecological Pest Control, Ministry of Education, Fuzhou 350002, China
| | - Xuanhao Chen
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Joint International Research Laboratory of Ecological Pest Control, Ministry of Education, Fuzhou 350002, China
| | - Qing Hou
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Joint International Research Laboratory of Ecological Pest Control, Ministry of Education, Fuzhou 350002, China
| | - Zhaoxia Liu
- College of Oceanology and Food Science, Quanzhou Normal University, Quanzhou 362000, China
| | - Gaoke Lei
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Joint International Research Laboratory of Ecological Pest Control, Ministry of Education, Fuzhou 350002, China
| | | | | | - Zhiguang Yuchi
- School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, China
| | - Minsheng You
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Ministerial and Provincial Joint Innovation Centre for Safety Production of Cross-Strait Crops, Fujian Agriculture and Forestry University, Fuzhou 350002, China
- Joint International Research Laboratory of Ecological Pest Control, Ministry of Education, Fuzhou 350002, China
| | - Yuanyuan Liu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Haixia Institute of Science and Technology, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Lei Xiong
- Institute of Plant Protection, Jiangxi Academy of Agricultural Sciences, State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops and College of Life Science, Institute of Applied Ecology, Fujian Agriculture and Forestry University, Nanchang 3302002, China
| |
Collapse
|
2
|
Lu JW, Jin L, Li MG, Yu BQ, Wen YF, Gu YQ, Lin Y, Yu XQ. A possible mechanism of Cry7Ab4 protein in delaying pupation of Plutella xylostella larvae. Front Immunol 2022; 13:849620. [PMID: 36159828 PMCID: PMC9491089 DOI: 10.3389/fimmu.2022.849620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 08/15/2022] [Indexed: 11/13/2022] Open
Abstract
Cry toxins produced by Bacillus thuringiensis (Bt) are well known for their insecticidal activities against Lepidopteran, Dipteran, and Coleopteran species. In our previous work, we showed that trypsin-digested full-length Cry7Ab4 protoxin did not have insecticidal activity against Plutella xylostella larvae but strongly inhibited their growth. In this paper, we expressed and purified recombinant active Cry7Ab4 toxic core from Escherichia coli for bioassay and identified its binding proteins. Interestingly, Cry7Ab4 toxic core exhibited activity to delay the pupation of P. xylostella larvae. Using protein pull-down assay, several proteins, including basic juvenile hormone-suppressible protein 1-like (BJSP-1), were identified from the midgut juice of P. xylostella larvae as putative Cry7Ab4-binding proteins. We showed that feeding P. xylostella larval Cry7Ab4 toxic core upregulated the level of BJSP-1 mRNA in the hemocytes and fat body and decreased the free juvenile hormone (JH) level in larvae. BJSP-1 interacted with Cry7Ab4 and bound to free JH in vitro. A possible mechanism of Cry7Ab4 in delaying the pupation of P. xylostella larvae was proposed.
Collapse
Affiliation(s)
- Jing-Wen Lu
- Fujian Provincial Key Laboratory of Biochemical Technology, Department of Bioengineering and Biotechnology, College of Chemical Engineering, Huaqiao University, Xiamen, China
| | - Liang Jin
- Fujian Provincial Key Laboratory of Biochemical Technology, Department of Bioengineering and Biotechnology, College of Chemical Engineering, Huaqiao University, Xiamen, China
| | - Meng-Ge Li
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
| | - Bryan Q. Yu
- International Department, The Affiliated High School of South China Normal University, Guangzhou, China
| | - Yang-Fan Wen
- Fujian Provincial Key Laboratory of Biochemical Technology, Department of Bioengineering and Biotechnology, College of Chemical Engineering, Huaqiao University, Xiamen, China
| | - Yu-Qing Gu
- Fujian Provincial Key Laboratory of Biochemical Technology, Department of Bioengineering and Biotechnology, College of Chemical Engineering, Huaqiao University, Xiamen, China
| | - Yi Lin
- Fujian Provincial Key Laboratory of Biochemical Technology, Department of Bioengineering and Biotechnology, College of Chemical Engineering, Huaqiao University, Xiamen, China
- *Correspondence: Yi Lin, ; Xiao-Qiang Yu,
| | - Xiao-Qiang Yu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Guangzhou Key Laboratory of Insect Development Regulation and Application Research, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China
- *Correspondence: Yi Lin, ; Xiao-Qiang Yu,
| |
Collapse
|
3
|
Foquet B, Castellanos AA, Song H. Comparative analysis of phenotypic plasticity sheds light on the evolution and molecular underpinnings of locust phase polyphenism. Sci Rep 2021; 11:11925. [PMID: 34099755 PMCID: PMC8184943 DOI: 10.1038/s41598-021-91317-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 05/24/2021] [Indexed: 02/05/2023] Open
Abstract
Locusts exhibit one of nature's most spectacular examples of complex phenotypic plasticity, in which changes in density cause solitary and cryptic individuals to transform into gregarious and conspicuous locusts forming large migrating swarms. We investigated how these coordinated alternative phenotypes might have evolved by studying the Central American locust and three closely related non-swarming grasshoppers in a comparative framework. By experimentally isolating and crowding during nymphal development, we induced density-dependent phenotypic plasticity and quantified the resulting behavioural, morphological, and molecular reaction norms. All four species exhibited clear plasticity, but the individual reaction norms varied among species and showed different magnitudes. Transcriptomic responses were species-specific, but density-responsive genes were functionally similar across species. There were modules of co-expressed genes that were highly correlated with plastic reaction norms, revealing a potential molecular basis of density-dependent phenotypic plasticity. These findings collectively highlight the importance of studying multiple reaction norms from a comparative perspective.
Collapse
Affiliation(s)
- Bert Foquet
- Department of Entomology, Texas A&M University, College Station, TX, USA.
- School of Biological Sciences, Illinois State University, Campus Box 4120, Normal, IL, 61790, USA.
| | - Adrian A Castellanos
- Department of Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX, USA
- Cary Institute of Ecosystem Studies, Millbrook, NY, USA
| | - Hojun Song
- Department of Entomology, Texas A&M University, College Station, TX, USA.
| |
Collapse
|
4
|
Short CA, Hatle JD, Hahn DA. Protein Stores Regulate When Reproductive Displays Begin in the Male Caribbean Fruit Fly. Front Physiol 2020; 11:991. [PMID: 32848894 PMCID: PMC7424033 DOI: 10.3389/fphys.2020.00991] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 07/20/2020] [Indexed: 11/13/2022] Open
Abstract
Many animals exhibit reproductive behavior that requires expenditure of valuable nutrients. In males of many species, competitive energetically demanding displays and the development of sexual ornaments require prior accumulation of nutrient stores. Males must coordinate nutrient stores with ornament development and reproductive displays or they risk depleting their resources mid-development or mid-display, reducing their chance of mating. Males may use nutrient stores to regulate their reproductive behavior. Amino acid reserves may be important for reproduction, but the roles of amino acid stores in initiating maturation and reproductive behavior are less studied than fat stores. Insects store amino acids as hexamerin storage proteins. Many fly species use a specific hexamerin, larval serum protein 2 (LSP-2), as both a juvenile storage medium and to store protein consumed after adult eclosion. Protein stored as LSP-2 has previously been suggested to regulate reproduction in females, but no role has been proposed for LSP-2 in regulating male maturation. We use males of the Caribbean fruit fly, Anastrepha suspensa, a species with nutrient-intensive male sexual displays to test whether LSP-2 stores regulate male reproductive displays. We fed adult A. suspensa males a diet with or without protein, then assayed these males for lsp-2 transcript abundance via qRT-PCR, LSP-2 protein abundance via Western blot, and reproductive display behavior via observation. We found that adult males with ad libitum dietary protein had greater lsp-2 transcript and protein abundance, earlier sexual display behavior, and were more likely to exhibit sexual display behavior than protein-deprived adult males. We show that lsp-2 knockdown via RNAi decreases the proportion of males exhibiting reproductive displays, particularly early in the onset of reproductive behavior. Our results suggest circulating LSP-2 protein stores regulate reproductive behavior in A. suspensa males, consistent with protein stores modulating reproduction in males with expensive reproductive strategies. Our results are consistent with hexamerin storage proteins performing dual roles of protein storage and protein signaling. Our work also has substantial practical applications because tephritid flies are a pest group and the timing and expression of male reproductive displays in this group are important for control efforts using the sterile insect technique.
Collapse
Affiliation(s)
- Clancy A. Short
- Department of Entomology and Nematology, The University of Florida, Gainesville, FL, United States
| | - John D. Hatle
- Department of Biology, The University of North Florida, Jacksonville, FL, United States
| | - Daniel A. Hahn
- Department of Entomology and Nematology, The University of Florida, Gainesville, FL, United States
| |
Collapse
|
5
|
Sagri E, Reczko M, Gregoriou ME, Tsoumani KT, Zygouridis NE, Salpea KD, Zalom FG, Ragoussis J, Mathiopoulos KD. Olive fly transcriptomics analysis implicates energy metabolism genes in spinosad resistance. BMC Genomics 2014; 15:714. [PMID: 25156405 PMCID: PMC4168201 DOI: 10.1186/1471-2164-15-714] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2014] [Accepted: 07/31/2014] [Indexed: 11/10/2022] Open
Abstract
Background The olive fly, Bactrocera oleae, is the most devastating pest of cultivated olives. Its control has been traditionally based on insecticides, mainly organophosphates and pyrethroids. In recent years, the naturalyte spinosad is used against the olive fly. As with other insecticides, spinosad is subject to selection pressures that have led to resistance development. Mutations in the α6 subunit of the nicotinic acetylcholine receptor (nAChR) have been implicated in spinosad resistance in several species (e.g., Drosophila melanogaster) but excluded in others (e.g., Musca domestica). Yet, additional mechanisms involving enhanced metabolism of detoxification enzymes (such as P450 monooxygenases or mixed function oxidases) have also been reported. In order to clarify the spinosad resistance mechanisms in the olive fly, we searched for mutations in the α6-subunit of the nAChR and for up-regulated genes in the entire transcriptome of spinosad resistant olive flies. Results The olive fly α6-subunit of the nAChR was cloned from the laboratory sensitive strain and a spinosad selected resistant line. The differences reflected silent nucleotide substitutions or conserved amino acid changes. Additionally, whole transcriptome analysis was performed in the two strains in order to reveal any underlying resistance mechanisms. Comparison of over 13,000 genes showed that in spinosad resistant flies nine genes were significantly over-expressed, whereas ~40 were under-expressed. Further functional analyses of the nine over-expressed and eleven under-expressed loci were performed. Four of these loci (Yolk protein 2, ATP Synthase FO subunit 6, Low affinity cationic amino acid transporter 2 and Serine protease 6) showed consistently higher expression both in the spinosad resistant strain and in wild flies from a resistant California population. On the other side, two storage protein genes (HexL1 and Lsp1) and two heat-shock protein genes (Hsp70 and Hsp23) were unfailingly under-expressed in resistant flies. Conclusion The observed nucleotide differences in the nAChR-α6 subunit between the sensitive and spinosad resistant olive fly strains did not advocate for the involvement of receptor mutations in spinosad resistance. Instead, the transcriptome comparison between the two strains indicated that several immune system loci as well as elevated energy requirements of the resistant flies might be necessary to lever the detoxification process. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-714) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Kostas D Mathiopoulos
- Department of Biochemistry and Biotechnology, University of Thessaly, Ploutonos 26, Larissa, Greece.
| |
Collapse
|
6
|
Gregorc A, Evans JD, Scharf M, Ellis JD. Gene expression in honey bee (Apis mellifera) larvae exposed to pesticides and Varroa mites (Varroa destructor). JOURNAL OF INSECT PHYSIOLOGY 2012; 58:1042-1049. [PMID: 22497859 DOI: 10.1016/j.jinsphys.2012.03.015] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Revised: 03/26/2012] [Accepted: 03/27/2012] [Indexed: 05/31/2023]
Abstract
Honey bee (Apis mellifera) larvae reared in vitro were exposed to one of nine pesticides and/or were challenged with the parasitic mite, Varroa destructor. Total RNA was extracted from individual larvae and first strand cDNAs were generated. Gene-expression changes in larvae were measured using quantitative PCR (qPCR) targeting transcripts for pathogens and genes involved in physiological processes, bee health, immunity, and/or xenobiotic detoxification. Transcript levels for Peptidoglycan Recognition Protein (PGRPSC), a pathogen recognition gene, increased in larvae exposed to Varroa mites (P<0.001) and were not changed in pesticide treated larvae. As expected, Varroa-parasitized brood had higher transcripts of Deformed Wing Virus than did control larvae (P<0.001). Varroa parasitism, arguably coupled with virus infection, resulted in significantly higher transcript abundances for the antimicrobial peptides abaecin, hymenoptaecin, and defensin1. Transcript levels for Prophenoloxidase-activating enzyme (PPOact), an immune end product, were elevated in larvae treated with myclobutanil and chlorothalonil (both are fungicides) (P<0.001). Transcript levels for Hexameric storage protein (Hsp70) were significantly upregulated in imidacloprid, fluvalinate, coumaphos, myclobutanil, and amitraz treated larvae. Definitive impacts of pesticides and Varroa parasitism on honey bee larval gene expression were demonstrated. Interactions between larval treatments and gene expression for the targeted genes are discussed.
Collapse
Affiliation(s)
- Aleš Gregorc
- Honey Bee Research and Extension Laboratory, Department of Entomology and Nematology, University of Florida, Natural Area Drive, Gainesville, FL 32611, USA.
| | | | | | | |
Collapse
|
7
|
Analysis of genes expression of Spodoptera exigua larvae upon AcMNPV infection. PLoS One 2012; 7:e42462. [PMID: 22860129 PMCID: PMC3409162 DOI: 10.1371/journal.pone.0042462] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Accepted: 07/09/2012] [Indexed: 02/07/2023] Open
Abstract
Background The impact of Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) infection on host gene expression in Spodoptera exigua 4th instar larvae was investigated through the use of 454 sequencing-based RNA-seq of cDNA libraries developed from insects challenged with active AcMNPV or heat-inactivated AcMNPV. Methodology/Principal Findings By comparing the two cDNA libraries, we show that 201 host genes are significantly up-regulated and 234 genes are significantly down-regulated by active AcMNPV infection. Down-regulated host genes included genes encoding antimicrobial peptides, namely three gloverin isoforms and an attacin, indicating that the viral infection actively repressed the expression of a portion of the host immune gene repertoire. Another interesting group of down-regulated host genes included genes encoding two juvenile hormone binding proteins and a hexamerin, all of which are involved in juvenile hormone regulation. The expression of these genes was enhanced by the topical application of Juvenile Hormone III (JHIII) in the insects challenged with heat-inactivated AcMNPV. However, infection with the active virus strongly suppresses the expression of these three genes, regardless of the absence or presence of JHIII. Conclusions/Significance Using RNA-seq, we have identified groups of immune-regulated and juvenile hormone-regulated genes that are suppressed by infection with active AcMNPV. This information and further studies on the regulation of host gene expression by AcMNPV will provide the tools needed to enhance the utility of the virus as an effective protein expression system and as an insecticide.
Collapse
|
8
|
Two storage hexamerins from the beet armyworm Spodoptera exigua: cloning, characterization and the effect of gene silencing on survival. BMC Mol Biol 2010; 11:65. [PMID: 20807423 PMCID: PMC2939506 DOI: 10.1186/1471-2199-11-65] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Accepted: 08/31/2010] [Indexed: 11/16/2022] Open
Abstract
Background In insects, hemocyanin superfamily proteins accumulate apparently to serve as sources of amino acids during metamorphosis, reproduction and development. Storage hexamerins are important members of the hemocyanin superfamily. Although insects possess storage hexamerins, very little is known about the character and specific functions of hexamerin 1 and storage protein 1 in insect development. Results To gain insight into the function of storage proteins in insects, cDNAs for two storage proteins were cloned from the fat body of Spodoptera exigua. S. exigua hexamerin 1 (SeHex) cDNA contained an open reading frame of 2124 nucleotides encoding a protein of 707 amino acids with a predicted molecular weight of 82.12 kDa. S. exigua storage protein 1 (SeSP1) cDNA contained an open reading frame of 2256 bp encoding a protein of 751 amino acids with a predicted molecular weight of ~88.84 kDa. Northern blotting analyses revealed that SeHex mRNA is expressed in the fat body, cuticle, midgut and Malpighian tubules and SeSP1 in fat body, Malpighian tubules and tracheae. SeHex and SeSP1 mRNAs were expressed in fat body at different levels from first instar larvae to pupae, with expression was much lower from first instar larvae to first-day fifth instar larvae. SeHex transcript expression was high in fat body of wandering larvae (pre-pupae) and steadily decreased to the seventh pupal day. SeSP1 transcript expression was high in fat body of wandering larvae, 2-day-old fifth instar larvae and 2-, 4- and 7-day-old pupae. SeHex and SeSP1 mRNAs levels were expressed lower than control on the condition of starvation at 12 h. Of insects injected with SeHex and SeSP1 dsRNA, 38.7% and 24.3% survived to 204 h after treatment, respectively. This was significantly lower than in the controls groups. Conclusions These findings provide new data on the tissue distribution, expression patterns and the function in starvation of storage proteins. RNA interference results revealed that storage protein genes are key in metamorphosis, reproduction and insect development. The results for SeHex and SeSP1 interference reveal that a potential method to control this pest is to disrupt the regulation of storage proteins.
Collapse
|
9
|
Martins JR, Nunes FMF, Cristino AS, Simões ZLP, Bitondi MMG. The four hexamerin genes in the honey bee: structure, molecular evolution and function deduced from expression patterns in queens, workers and drones. BMC Mol Biol 2010; 11:23. [PMID: 20346164 PMCID: PMC2861669 DOI: 10.1186/1471-2199-11-23] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Accepted: 03/26/2010] [Indexed: 11/26/2022] Open
Abstract
Background Hexamerins are hemocyanin-derived proteins that have lost the ability to bind copper ions and transport oxygen; instead, they became storage proteins. The current study aimed to broaden our knowledge on the hexamerin genes found in the honey bee genome by exploring their structural characteristics, expression profiles, evolution, and functions in the life cycle of workers, drones and queens. Results The hexamerin genes of the honey bee (hex 70a, hex 70b, hex 70c and hex 110) diverge considerably in structure, so that the overall amino acid identity shared among their deduced protein subunits varies from 30 to 42%. Bioinformatics search for motifs in the respective upstream control regions (UCRs) revealed six overrepresented motifs including a potential binding site for Ultraspiracle (Usp), a target of juvenile hormone (JH). The expression of these genes was induced by topical application of JH on worker larvae. The four genes are highly transcribed by the larval fat body, although with significant differences in transcript levels, but only hex 110 and hex 70a are re-induced in the adult fat body in a caste- and sex-specific fashion, workers showing the highest expression. Transcripts for hex 110, hex 70a and hex70b were detected in developing ovaries and testes, and hex 110 was highly transcribed in the ovaries of egg-laying queens. A phylogenetic analysis revealed that HEX 110 is located at the most basal position among the holometabola hexamerins, and like HEX 70a and HEX 70c, it shares potential orthology relationship with hexamerins from other hymenopteran species. Conclusions Striking differences were found in the structure and developmental expression of the four hexamerin genes in the honey bee. The presence of a potential binding site for Usp in the respective 5' UCRs, and the results of experiments on JH level manipulation in vivo support the hypothesis of regulation by JH. Transcript levels and patterns in the fat body and gonads suggest that, in addition to their primary role in supplying amino acids for metamorphosis, hexamerins serve as storage proteins for gonad development, egg production, and to support foraging activity. A phylogenetic analysis including the four deduced hexamerins and related proteins revealed a complex pattern of evolution, with independent radiation in insect orders.
Collapse
Affiliation(s)
- Juliana R Martins
- Faculdade de Medicina de Ribeirão Preto, Departamento de Genética, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | | | | | | | | |
Collapse
|
10
|
Age-dependent cyclic locomotor activity in the cricket, Gryllus bimaculatus, and the effect of adipokinetic hormone on locomotion and excitability. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2010; 196:271-83. [DOI: 10.1007/s00359-010-0513-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 02/13/2010] [Accepted: 02/18/2010] [Indexed: 02/02/2023]
|
11
|
Cristino AS, Nunes FMF, Barchuk AR, Aguiar-Coelho VM, Simões ZLP, Bitondi MMG. Organization, evolution and transcriptional profile of hexamerin genes of the parasitic wasp Nasonia vitripennis (Hymenoptera: Pteromalidae). INSECT MOLECULAR BIOLOGY 2010; 19 Suppl 1:137-146. [PMID: 20167024 DOI: 10.1111/j.1365-2583.2009.00970.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Hexamerins and prophenoloxidases (PPOs) proteins are members of the arthropod-haemocyanin superfamily. In contrast to haemocyanin and PPO, hexamerins do not bind oxygen, but mainly play a role as storage proteins that supply amino acids for insect metamorphosis. We identified seven genes encoding hexamerins, three encoding PPOs, and one hexamerin pseudogene in the genome of the parasitoid wasp Nasonia vitripennis. A phylogenetic analysis of hexamerins and PPOs from this wasp and related proteins from other insect orders suggests an essentially order-specific radiation of hexamerins. Temporal and spatial transcriptional profiles of N. vitripennis hexamerins suggest that they have physiological functions other than metamorphosis, which are arguably coupled with its lifestyle.
Collapse
Affiliation(s)
- A S Cristino
- The Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia.
| | | | | | | | | | | |
Collapse
|
12
|
Wolschin F, Gadau J. Deciphering proteomic signatures of early diapause in Nasonia. PLoS One 2009; 4:e6394. [PMID: 19636376 PMCID: PMC2712079 DOI: 10.1371/journal.pone.0006394] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2009] [Accepted: 05/26/2009] [Indexed: 11/18/2022] Open
Abstract
Insect diapause is an alternative life-history strategy used to increase longevity and survival in harsh environmental conditions. Even though some aspects of diapause are well investigated, broader scale studies that elucidate the global metabolic adjustments required for this remarkable trait, are rare. In order to better understand the metabolic changes during early insect diapause, we used a shotgun proteomics approach on early diapausing and non-diapausing larvae of the recently sequenced hymenopteran model organism Nasonia vitripennis. Our results deliver insights into the molecular underpinnings of diapause in Nasonia and corroborate previously reported diapause-associated features for invertebrates, such as a diapause-dependent abundance change for heat shock and storage proteins. Furthermore, we observed a diapause-dependent switch in enzymes involved in glycerol synthesis and a vastly changed capacity for protein synthesis and degradation. The abundance of structural proteins and proteins involved in protein synthesis decreased with increasing diapause duration, while the abundance of proteins likely involved in diapause maintenance (e.g. ferritins) increased. Only few potentially diapause-specific proteins were identified suggesting that diapause in Nasonia relies to a large extent on a modulation of pre-existing pathways. Studying a diapause syndrome on a proteomic level rather than isolated pathways or physiological networks, has proven to be an efficient and successful avenue to understand molecular mechanisms involved in diapause.
Collapse
Affiliation(s)
- Florian Wolschin
- School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America.
| | | |
Collapse
|
13
|
Korb J, Hartfelder K. Life history and development--a framework for understanding developmental plasticity in lower termites. Biol Rev Camb Philos Soc 2008; 83:295-313. [PMID: 18979593 DOI: 10.1111/j.1469-185x.2008.00044.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Termites (Isoptera) are the phylogenetically oldest social insects, but in scientific research they have always stood in the shadow of the social Hymenoptera. Both groups of social insects evolved complex societies independently and hence, their different ancestry provided them with different life-history preadaptations for social evolution. Termites, the 'social cockroaches', have a hemimetabolous mode of development and both sexes are diploid, while the social Hymenoptera belong to the holometabolous insects and have a haplodiploid mode of sex determination. Despite this apparent disparity it is interesting to ask whether termites and social Hymenoptera share common principles in their individual and social ontogenies and how these are related to the evolution of their respective social life histories. Such a comparison has, however, been much hampered by the developmental complexity of the termite caste system, as well as by an idiosyncratic terminology, which makes it difficult for non-termitologists to access the literature. Here, we provide a conceptual guide to termite terminology based on the highly flexible caste system of the "lower termites". We summarise what is known about ultimate causes and underlying proximate mechanisms in the evolution and maintenance of termite sociality, and we try to embed the results and their discussion into general evolutionary theory and developmental biology. Finally, we speculate about fundamental factors that might have facilitated the unique evolution of complex societies in a diploid hemimetabolous insect taxon. This review also aims at a better integration of termites into general discussions on evolutionary and developmental biology, and it shows that the ecology of termites and their astounding phenotypic plasticity have a large yet still little explored potential to provide insights into elementary evo-devo questions.
Collapse
Affiliation(s)
- Judith Korb
- Biologie I, Universität Regensburg D-93040 Regensburg, Germany.
| | | |
Collapse
|
14
|
Anand AN, Lorenz MW. Age-dependent changes of fat body stores and the regulation of fat body lipid synthesis and mobilisation by adipokinetic hormone in the last larval instar of the cricket, Gryllus bimaculatus. JOURNAL OF INSECT PHYSIOLOGY 2008; 54:1404-1412. [PMID: 18761344 DOI: 10.1016/j.jinsphys.2008.08.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2008] [Revised: 07/30/2008] [Accepted: 08/04/2008] [Indexed: 05/26/2023]
Abstract
Data on the hormonal regulation of the formation and mobilisation of fat body stores are presented and discussed in relation to general parameters of last instar larval development such as growth, food intake, and moulting. Crickets feed voraciously during the first half of the last larval stage. With the onset of feeding, fat body lipid synthesis increases, leading to increasing lipid stores in the fat body with a maximum reached on day 5. Lipid (42% of fat body fresh mass) is the main constituent of the fat body stores, followed by protein (6%) and glycogen (2%). During the second half of the last larval stage, feeding activity dramatically decreases, the glycogen reserves are depleted but lipid and protein reserves in the fat body remain at a high level except for the last day of the last larval stage when lipid and protein in the fat body are also largely depleted. The process of moulting consumes almost three quarters of the caloric equivalents that were acquired during the last larval stage. Adipokinetic hormone (AKH) inhibits effectively the synthesis of lipids in the larval fat body. Furthermore, AKH stimulates lipid mobilisation by activating fat body triacylglycerol lipase (TGL) in last larval and adult crickets. Both effects of AKH are weaker in larvae than in adults. This is the first report on the age-dependent basal activity of TGL in larval and adult insects. In addition, for the first time, an activation of TGL by AKH in a larval insect is shown.
Collapse
Affiliation(s)
- Anurag N Anand
- Department of Animal Ecology 1, University of Bayreuth, 95440 Bayreuth, Germany
| | | |
Collapse
|
15
|
Nijhout HF, Reed MC. A mathematical model for the regulation of juvenile hormone titers. JOURNAL OF INSECT PHYSIOLOGY 2008; 54:255-264. [PMID: 18022634 DOI: 10.1016/j.jinsphys.2007.09.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2007] [Accepted: 09/27/2007] [Indexed: 05/25/2023]
Abstract
The titer of juvenile hormone (JH) is determined by three factors: its rate of synthesis, its rate of degradation, and the degree to which JH is protected from degradation by binding to a diversity of JH-binding proteins. All three of these factors vary throughout the life history of an insect and contribute to variation in the JH titer. The relative importance of each of these factors in determining variation in the JH titer is not known and can, presumably, differ in different life stages and different species. Here we develop a mathematical model for JH synthesis, degradation, and sequestration that allows us to describe quantitatively how each of these contribute to the titer of total JH and free JH in the hemolymph. Our model allows for a diversity of JH-binding proteins with different dissociation constants, and also for a number of different modes of degradation and inactivation. The model can be used to analyze whether data on synthesis and degradation are compatible with the observed titer data. We use the model to analyze two data sets, from Manduca and Gryllus, and show that in both cases, the known data on synthesis and degradation cannot account for the observed JH titers because the role of JH sequestration by binding proteins is greatly underestimated, and/or the in vivo rate of JH degradation is greatly overestimated. These analyses suggest that there is a critical need to develop a better understanding of the in vivo role of synthesis, sequestration and degradation in JH titer regulation.
Collapse
|
16
|
Scharf ME, Buckspan CE, Grzymala TL, Zhou X. Regulation of polyphenic caste differentiation in the termite Reticulitermes flavipes by interaction of intrinsic and extrinsic factors. J Exp Biol 2007; 210:4390-8. [DOI: 10.1242/jeb.010876] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Polyphenism is a key strategy used by solitary insects to adapt to changing environmental conditions and by eusocial insects for existing collaboratively in a social environment. In social insects, the morphogenetic juvenile hormone(JH) is often involved in directing the differentiation of polyphenic behavioral castes. The present study examines the effects of JH, environment and feeding on caste polyphenism in a eusocial insect, the termite Reticulitermes flavipes (Kollar). Our approach included a combination of model JH bioassays, SDS-PAGE and western blotting. Our findings revealed significant temperature-dependent effects on (1) JH-induced soldier caste differentiation, (2) abundance of soldier-inhibitory hexamerin proteins and(3) JH-sequestration by hexamerin proteins. Additionally, although it appears to be dependent on a complex interaction of factors, feeding apparently plays a significant upstream role in enhancing hexamerin accumulation under normal colony conditions. These findings offer important new information on termite eusocial polyphenism by providing the first mechanistic evidence linking an intrinsic caste regulatory factor (hexamerin proteins) to an upstream extrinsic factor (environment) and a downstream response (caste differentiation). These observations are consistent with the hypothesis that the hexamerins serve as an environmentally and nutritionally responsive switching mechanism that regulates termite caste polyphenism.
Collapse
Affiliation(s)
- Michael E. Scharf
- Entomology and Nematology Department, University of Florida,Gainesville, FL 32611-0620, USA
| | - Caitlin E. Buckspan
- Entomology and Nematology Department, University of Florida,Gainesville, FL 32611-0620, USA
| | - Traci L. Grzymala
- Entomology and Nematology Department, University of Florida,Gainesville, FL 32611-0620, USA
| | - Xuguo Zhou
- Entomology and Nematology Department, University of Florida,Gainesville, FL 32611-0620, USA
| |
Collapse
|
17
|
Spiliotopoulos A, Gkouvitsas T, Fantinou A, Kourti A. Expression of a cDNA encoding a member of the hexamerin storage proteins from the moth Sesamia nonagrioides (Lef.) during diapause. Comp Biochem Physiol B Biochem Mol Biol 2007; 148:44-54. [PMID: 17537657 DOI: 10.1016/j.cbpb.2007.04.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2007] [Revised: 04/19/2007] [Accepted: 04/19/2007] [Indexed: 11/19/2022]
Abstract
We isolated and sequenced a cDNA clone corresponding to a storage protein (SnoSP1) from the corn stalk borer Sesamia nonagrioides (Lef.). The cDNA for SnoSP1 (2403 bp) codes for a 751 residue protein with predicted molecular mass of 88.3 kDa and calculated isoelectric point pI=8.72. A signal peptide of 16 amino acids is present at the N-terminus and the protein contained conserved insect larval storage protein signature sequence patterns. Multiple alignment analysis of the amino acid sequence revealed that SnoSP1 is most similar to the basic juvenile hormone-suppressible protein 2 precursor (TniSP2) from Trichoplusia ni (71% identity) and other moderately methionine-rich hexamers. According to both phylogenetic analyses and the criteria of amino acid composition, SnoSP1 belongs to the subfamily of moderately methionine-rich storage proteins (3.7% methionine, 11% aromatic amino acid). Treatment with the juvenile hormone analog, methroprene, after head ligation of larvae, is found to suppress the level of SnoSP1 gene, indicating hormonal effects at the transcriptional level. We also examined developmental profiles of SnoSP1 expression in fat body from diapausing and non-diapausing larvae by semi-quantitative and Real-Time PCR assays. In non diapause conditions the abundance of SnoSP1 was found in high levels during the last larval stage and decreased gradually during the pupal stage. Very low levels of this mRNA were detected in larvae that were preparing to enter diapause, but mRNA dramatically increased in those that were in diapause as well as in those that terminate diapause.
Collapse
Affiliation(s)
- Anastasios Spiliotopoulos
- Department of Agricultural Biotechnology, Agricultural University of Athens, Iera Odos 75, Athens 11855, Greece
| | | | | | | |
Collapse
|
18
|
Zhou X, Tarver MR, Scharf ME. Hexamerin-based regulation of juvenile hormone-dependent gene expression underlies phenotypic plasticity in a social insect. Development 2007; 134:601-10. [PMID: 17215309 DOI: 10.1242/dev.02755] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Worker termites of the genus Reticulitermes are temporally-arrested juvenile forms that can terminally differentiate into adultsoldier- or reproductive-caste phenotypes. Soldier-caste differentiation is a developmental transition that is induced by high juvenile hormone (JH) titers. Recently, a status quo hexamerin mechanism was identified, which reduces JH efficacy and maximizes colony fitness via the maintenance of high worker-caste proportions. Our goal in these studies was to investigate more thoroughly the influences of the hexamerins on JH-dependent gene expression in termite workers. Our approach involved RNA interference (RNAi), bioassays and quantification of gene expression. We first investigated the expression of 17 morphogenesis-associated genes in response to RNAi-based hexamerin silencing. Hexamerin silencing resulted in significant downstream impacts on 15 out of the 17 genes, suggesting that these genes are members of a JH-responsive genomic network. Next, we compared gene-expression profiles in workers after RNAi-based hexamerin silencing to that of (i) untreated workers that were held away from the colony; and (ii) workers that were also held away from the colony, but with ectopic JH. Here, although there was no correlation between hexamerin silencing and colony-release effects, we observed a significant correlation between hexamerin silencing and JH-treatment effects. These findings provide further evidence supporting the hypothesis that the hexamerins modulate JH availability, thus limiting the impacts of JH on termite caste polyphenism. Results are discussed in a context relative to outstanding questions on termite developmental biology, particularly on regulatory gene networks that respond to JH-, colony- and environmental-cues.
Collapse
Affiliation(s)
- Xuguo Zhou
- Entomology and Nematology Department, University of Florida, Gainesville, FL 32611-0620, USA
| | | | | |
Collapse
|
19
|
Zhou X, Tarver MR, Bennett GW, Oi FM, Scharf ME. Two hexamerin genes from the termite Reticulitermes flavipes: Sequence, expression, and proposed functions in caste regulation. Gene 2006; 376:47-58. [PMID: 16580793 DOI: 10.1016/j.gene.2006.02.002] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2005] [Revised: 02/01/2006] [Accepted: 02/02/2006] [Indexed: 11/19/2022]
Abstract
Previous molecular studies on the termite Reticulitermes flavipes have revealed that two hexamerin proteins serve an important status quo role in the regulation of juvenile hormone (JH)-dependent caste differentiation. Here, we report sequence data and other experimental evidence suggesting how these two hexamerins function in achieving caste regulation. The two hexamerin genes, named Hex-1 and Hex-2, encode highly unique sequence features relative to the 100+ other known insect hexamerins. These features include a long hydrophobic tail and prenylation motif in Hex-1, and a long hydrophilic insertion plus several putative protease cleavage sites in Hex-2. Both hexamerin genes are primarily expressed in fat body tissue, but only Hex-2 expression is substantially induced by JH. SDS-PAGE showed that the hexamerin proteins constitute a major proportion of total soluble termite protein. Also, although each protein occurs in both the membrane and soluble protein fractions, Hex-2 has stronger membrane affinity. Anti-JH antiserum specifically recognizes hemolymph-soluble Hex-1 protein, supporting that the unique prenylation site in Hex-1 facilitates covalent JH binding to the primary amino acid chain. Finally, increased ratios of Hex-2 to Hex-1 transcription occur in caste phenotypes and developmental stages that differentiate in response to rising JH titers. Two main conclusions can be taken from these studies. First, elevated ratios of Hex-2 to Hex-1 expression are associated with caste phenotypes that differentiate in response to rising JH titers (i.e., workers, presoldiers and soldiers). Second, due to their unique structural features and other observed characteristics, our findings support the hypothesis that the two hexamerins participate in the regulation of caste-differentiation by modulating JH availability.
Collapse
Affiliation(s)
- X Zhou
- Toxicology Laboratory, Entomology and Nematology Department, University of Florida, Bldg. 970-Natural Area Dr., PO Box 110620, Gainesville, FL 32611-0620, USA
| | | | | | | | | |
Collapse
|