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Lv Z, Yu S, Zhao Y, Yang Z. Silence of Aminopeptidase N 2 gene reveals the trade-offs for acquiring Cry1Ac resistance in Plutella xylostella. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2024; 116:e22131. [PMID: 39016064 DOI: 10.1002/arch.22131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Revised: 06/12/2024] [Accepted: 06/29/2024] [Indexed: 07/18/2024]
Abstract
Bacillus thuringiensis (Bt) is widely used as a biopesticide worldwide. To date, at least eight pest species have been found to be resistant to Bt in the field. As the first pest that was reported having resistance to Bt in the field, considerable research has been done on the mechanisms of Bt resistance in Plutella xylostella. However, whether the acquisition of Bt resistance by P. xylostella comes at a fitness cost is also a valuable question. In this study, Aminopeptidase-N 2 (APN2), a Cry toxin receptor gene of P. xylostella, was knocked down by RNA interference, resulting in improved resistance to Cry1Ac. It was also found that larval mortality of APN2 knockdown P. xylostella was significantly higher than that of the control, while the pupation rate, pupal weight, eclosion rate, fecundity (egg/female), hatchability, and female adult longevity were significantly lower in APN2 knockdown P. xylostella than in the control. These results illustrate that if Cry1Ac resistance was obtained only through the reduction of APN2 expression, P. xylostella would need to incur some fitness costs for it.
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Affiliation(s)
- Zhuohong Lv
- Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, College of Plant Protection, Hunan Agricultural University, Changsha, China
- Yuelushan Laboratory, Changsha, China
| | - Shuwen Yu
- Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, College of Plant Protection, Hunan Agricultural University, Changsha, China
| | - Yafei Zhao
- Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, College of Plant Protection, Hunan Agricultural University, Changsha, China
| | - Zhongxia Yang
- Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, College of Plant Protection, Hunan Agricultural University, Changsha, China
- Yuelushan Laboratory, Changsha, China
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Zhu S, Chen X, Xia S, Li Q, Ye Z, Zhao S, Liu K, Liu F. Hexamerin and allergen are required for female reproduction in the American cockroach, Periplaneta americana. INSECT SCIENCE 2024; 31:186-200. [PMID: 37327125 DOI: 10.1111/1744-7917.13218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 04/10/2023] [Accepted: 05/04/2023] [Indexed: 06/18/2023]
Abstract
Reproduction is of great importance for the continuation of the species. In insects, the fat body is the major tissue for nutrient storage and involved in vitellogenesis, which is essential for female reproduction. Here, 2 proteins, hexamerin and allergen, were separated from the fat bodies of adult female American cockroaches (Periplaneta americana) and identified as storage proteins, encoding for 733 amino acids with molecular weight of 87.88 kDa and 686 amino acids with molecular weight of 82.18 kDa, respectively. The encoding genes of these 2 storage proteins are mainly expressed in the fat body. RNA interference-mediated knockdown of Hexamerin and Allergen in the early stage of the first reproductive cycle in females suppressed vitellogenesis and ovarian maturation, indicating that these storage proteins are involved in controlling reproduction. Importantly, the expression of Hexamerin and Allergen was repressed by knockdown of the juvenile hormone (JH) receptor gene Met and the primary response gene Kr-h1, and was induced by methoprene, a JH analog, in both in vivo and in vitro experiments. Altogether, we have determined that hexamerin and allergen are identified as storage proteins and play an important role in promoting female reproduction in the American cockroach. The expression of their encoding genes is induced by JH signaling. Our data reveal a novel mechanism by which hexamerin and allergen are necessary for JH-stimulated female reproduction.
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Affiliation(s)
- Shiming Zhu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, China
- Guangmeiyuan R&D Center, Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, South China Normal University, Meizhou, Guangdong Province, China
- Guangdong Laboratory for Lingnan Modern Agriculture, South China Agricultural University, Guangzhou, China
| | - Xiaoyi Chen
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, China
| | - Sishi Xia
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, China
| | - Qin Li
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, China
| | - Ziqi Ye
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, China
| | - Shaoting Zhao
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, China
| | - Kexin Liu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, China
| | - Fangfang Liu
- Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, Institute of Insect Science and Technology & School of Life Sciences, South China Normal University, Guangzhou, China
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Kahilainen A, Oostra V, Somervuo P, Minard G, Saastamoinen M. Alternative developmental and transcriptomic responses to host plant water limitation in a butterfly metapopulation. Mol Ecol 2022; 31:5666-5683. [PMID: 34516691 DOI: 10.1111/mec.16178] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 08/06/2021] [Accepted: 09/02/2021] [Indexed: 01/13/2023]
Abstract
Predicting how climate change affects biotic interactions poses a challenge. Plant-insect herbivore interactions are particularly sensitive to climate change, as climate-induced changes in plant quality cascade into the performance of insect herbivores. Whereas the immediate survival of herbivore individuals depends on plastic responses to climate change-induced nutritional stress, long-term population persistence via evolutionary adaptation requires genetic variation for these responses. To assess the prospects for population persistence under climate change, it is therefore crucial to characterize response mechanisms to climate change-induced stressors, and quantify their variability in natural populations. Here, we test developmental and transcriptomic responses to water limitation-induced host plant quality change in a Glanville fritillary butterfly (Melitaea cinxia) metapopulation. We combine nuclear magnetic resonance spectroscopy on the plant metabolome, larval developmental assays and an RNA sequencing analysis of the larval transcriptome. We observed that responses to feeding on water-limited plants, in which amino acids and aromatic compounds are enriched, showed marked variation within the metapopulation, with individuals of some families performing better on control and others on water-limited plants. The transcriptomic responses were concordant with the developmental responses: families exhibiting opposite developmental responses also produced opposite transcriptomic responses (e.g. in growth-associated transcripts). The divergent responses in both larval development and transcriptome are associated with differences between families in amino acid catabolism and storage protein production. The results reveal intrapopulation variability in plasticity, suggesting that the Finnish M. cinxia metapopulation harbours potential for buffering against drought-induced changes in host plant quality.
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Affiliation(s)
- Aapo Kahilainen
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, P.O. Box 65, Helsinki, FIN-00014, Finland
| | - Vicencio Oostra
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, P.O. Box 65, Helsinki, FIN-00014, Finland.,Department of Evolution, Ecology and Behaviour, University of Liverpool, Crown Street, Liverpool, L69 7ZB, United Kingdom
| | - Panu Somervuo
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, P.O. Box 65, Helsinki, FIN-00014, Finland
| | - Guillaume Minard
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, INRAe, VetAgro Sup, UMR Ecologie Microbienne, Villeurbanne, France
| | - Marjo Saastamoinen
- Organismal and Evolutionary Biology Research Programme, University of Helsinki, P.O. Box 65, Helsinki, FIN-00014, Finland.,Helsinki Institute of Life Science, University of Helsinki, Finland
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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.
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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,
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Metarhizium Anisopliae Challenges Immunity and Demography of Plutella xylostella. INSECTS 2020; 11:insects11100694. [PMID: 33065996 PMCID: PMC7600445 DOI: 10.3390/insects11100694] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 10/05/2020] [Accepted: 10/09/2020] [Indexed: 12/18/2022]
Abstract
Simple Summary The diamondback moth, Plutella xylostella, is a destructive pest of cruciferous crops worldwide. Integrated pest management (IPM) strategies, largely involve the use chemical pesticides which are harmful for the environment and human health. In this study, the virulence of three species of entomopathogenic fungi were tested. Metarhizium anisopliae proved to be the most effective by killing more than 90% of the population. Based on which the fungus was selected to study the host-pathogen immune interactions. More precisely, after infection, superoxide dismutase (SOD) and phenoloxidase (PO), two major enzymes involved in immune response, were studied at different time points. The fungus gradually weakened the enzyme activities as the time progressed, indicating that physiological attributes of host were adversely affected. The expression of immune-related genes (Defensin, Spaetzle, Cecropin, Lysozyme, and Hemolin) varied on different time points. Moreover, the fungus negatively impacted the development of the host by reducing the life span and egg laying ability. Thus, M. anisopliae can become a potent prospect for the control of this pest. This information will also reinforce the development of policies for biocontrol-based pest management. Abstract Entomopathogenic fungi are naturally existing microbes, that can serve as a key regulator of insect pests in integrated pest management strategies. Besides having no hazardous effects on the environment, these entomopathogens are alternatives to synthetic insecticides that can control notorious insect-like Plutella xylostella, a destructive pest of cruciferous crops. Three different species of entomopathogenic fungi were evaluated before the selection (high larval mortality and least LC50) of Metarhizum anisopliae. The study was designed to investigate the mortality, development, and immune responses of P. xylostella when challenged with M. anisopliae, a naturally existing soil-borne entomopathogenic fungus. M. anisopliae resulted in high pest mortality by killing 93% of larvae. However, no statistically significant effect on hemocyte concentration was observed. The activity of enzymes (Phenoloxidase and Superoxide dismutase) and immune genes (Defensin, Spaetzle, Cecropin, Lysozyme, and Hemolin) did vary at different time points (24, 48, 72 and 96 h) after exposure to M. anisopliae. Disturbance in the biological cycles of P. xylostella was also detected, significantly shorter adult life span (8.11:6.87, M:F) and reduced fecundity (101 eggs/female) were observed along with disturbed larval and pupal duration. Results suggest that M. anisopliae can efficiently hinder the P. xylostella defense and developmental system, resulting in mortality and disturbed demography.
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Wang C, Jin F, De Mandal S, Zeng L, Zhang Y, Hua Y, Hong Y, Zhao C, Li J, Li D, Xu X. Insights into the venom protein components of the egg parasitoid Anastatus japonicus (Hymenoptera: Eupelmidae). PEST MANAGEMENT SCIENCE 2020; 76:2113-2126. [PMID: 31951096 DOI: 10.1002/ps.5750] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 01/08/2020] [Accepted: 01/17/2020] [Indexed: 06/10/2023]
Abstract
BACKGROUND Parasitoid venom is composed of a complex mixture of various active substances with different biological functions and is injected in the host during the parasitoid oviposition. Anastatus japonicus (Hymenoptera: Eupelmidae) is an egg parasite of Tessaratoma papillosa (Hemiptera: Tessaratomidae). Although the venom of this egg parasitoid plays an important role in the parasitic process, relatively little work has been done to address the mechanism. RESULTS In the present study, proteomic analysis was performed to identify the proteins that play an important role in the parasitic process of A. japonicus. A total of 2084 proteins were identified, including 81 putative venom proteins, most of which were identified as Hexamerin, Chitinase 2, Calreticulin, Heat shock protein 83-like, Serine protease, Arginine kinase, Phosphoserine aminotransferase and Actin protein. Together the before (Be) and after (Af) parasitization venom contains 1628 proteins, including 212 DEPs with 181 and 31 significantly up-regulated and down-regulated respectively. In addition, 10 differentially expressed proteins (DEPs) with fold change ≥8.71 were subjected to RT-qPCR to validate the proteomic data. The differential expression analysis revealed that nine proteins were specifically present in the pre-parasitic venom, whereas 26 proteins were specific to the post-parasitic treatments. Results of RT-qPCR analysis showed high expression of the selected DEPs which further validated our proteomics data. CONCLUSION These new proteomic data greatly enrich our current knowledge about key venom proteins associated with parasitic process in A. japonicus and contribute to better understanding of the parasitic mechanisms leading to the development of new biological control strategies. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Chengxing Wang
- Laboratory of Bio-Pesticide Creation and Application of Guangdong Province, Department of Entomology, College of Agriculture, South China Agricultural University, Guangzhou, China
- Plant Protection Research Institute, , Guangdong Academy of Agricultural Sciences/Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou 510640, China
| | - Fengliang Jin
- Laboratory of Bio-Pesticide Creation and Application of Guangdong Province, Department of Entomology, College of Agriculture, South China Agricultural University, Guangzhou, China
| | - Surajit De Mandal
- Laboratory of Bio-Pesticide Creation and Application of Guangdong Province, Department of Entomology, College of Agriculture, South China Agricultural University, Guangzhou, China
| | - Lu Zeng
- Laboratory of Bio-Pesticide Creation and Application of Guangdong Province, Department of Entomology, College of Agriculture, South China Agricultural University, Guangzhou, China
| | - Yuxin Zhang
- Laboratory of Bio-Pesticide Creation and Application of Guangdong Province, Department of Entomology, College of Agriculture, South China Agricultural University, Guangzhou, China
| | - Yanyan Hua
- Laboratory of Bio-Pesticide Creation and Application of Guangdong Province, Department of Entomology, College of Agriculture, South China Agricultural University, Guangzhou, China
| | - Yingying Hong
- Laboratory of Bio-Pesticide Creation and Application of Guangdong Province, Department of Entomology, College of Agriculture, South China Agricultural University, Guangzhou, China
| | - Can Zhao
- Plant Protection Research Institute, , Guangdong Academy of Agricultural Sciences/Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou 510640, China
| | - Junzhai Li
- Laboratory of Bio-Pesticide Creation and Application of Guangdong Province, Department of Entomology, College of Agriculture, South China Agricultural University, Guangzhou, China
- Plant Protection Research Institute, , Guangdong Academy of Agricultural Sciences/Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou 510640, China
| | - Dunsong Li
- Plant Protection Research Institute, , Guangdong Academy of Agricultural Sciences/Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou 510640, China
| | - Xiaoxia Xu
- Laboratory of Bio-Pesticide Creation and Application of Guangdong Province, Department of Entomology, College of Agriculture, South China Agricultural University, Guangzhou, China
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Liu C, Zhu J, Ma J, Zhang J, Wang X, Zhang R. A novel hexamerin with an unexpected contribution to the prophenoloxidase activation system of the Chinese oak silkworm, Antheraea pernyi. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2020; 103:e21648. [PMID: 31808198 DOI: 10.1002/arch.21648] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/12/2019] [Accepted: 11/14/2019] [Indexed: 06/10/2023]
Abstract
Hexamerin was originally identified as a storage protein but later confirmed to be involved in many physiological processes. In the present study, we cloned and characterized a novel hexamerin complementary DNA sequence from the Chinese oak silkworm, Antheraea pernyi (Ap-hexamerin), which shows high homology with reported insect methionine-rich hexamerins. The tissue distribution and time course of expression demonstrated that Ap-hexamerin was predominantly synthesized in the fat body and the expression level was significantly increased in response to the microbial challenge, suggesting the relevance of Ap-hexamerin to immune responses. In further immune functional studies, Ap-hexamerin was confirmed to take part in the upregulation of prophenoloxidase (PPO) activation in A. pernyi haemolymph triggered by pathogen-associated molecular patterns (PAMPs). Additional molecular interaction analysis revealed that Ap-hexamerin is capable of binding the PAMPs used in the phenoloxidase assay, suggesting hexamerin in A. pernyi may positively regulate haemolymph PPO activation, acting as a pattern recognition protein.
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Affiliation(s)
- Chengbao Liu
- Department of Biopharmaceutics, School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning, China
| | - Jinye Zhu
- Department of Biopharmaceutics, School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning, China
| | - Jingjing Ma
- Department of Biopharmaceutics, School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning, China
| | - Jinghai Zhang
- Department of Biomedical Engineering, School of Medical Devices, Shenyang Pharmaceutical University, Shenyang, Liaoning, China
| | - Xialu Wang
- Department of Biomedical Engineering, School of Medical Devices, Shenyang Pharmaceutical University, Shenyang, Liaoning, China
| | - Rong Zhang
- Department of Biopharmaceutics, School of Life Science and Bio-Pharmaceutics, Shenyang Pharmaceutical University, Shenyang, Liaoning, China
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Vilcinskas A, Vogel H. Seasonal phenotype-specific transcriptional reprogramming during metamorphosis in the European map butterfly Araschnia levana. Ecol Evol 2016; 6:3476-3485. [PMID: 27127610 PMCID: PMC4842023 DOI: 10.1002/ece3.2120] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 03/12/2016] [Accepted: 03/21/2016] [Indexed: 11/14/2022] Open
Abstract
The European map butterfly (Araschnia levana) is a classic example of seasonal polyphenism because the spring and summer imagoes display two distinct morphological phenotypes. The light regime and temperature during larval and prepupal development determine whether or not the pupae commit to diapause and overwintering and thus whether spring or summer imagoes emerge. We used suppression subtractive hybridization to experimentally screen for genes that are differentially expressed in prepupae committed either to accelerated metamorphosis and egg production or diapause and overwintering. The range and ontology of the differentially expressed genes in prepupae developing from larvae exposed either to long‐day (LD) or short‐day (SD) conditions revealed fundamental differences. The SD prepupae preferentially expressed genes related to cuticle formation and immunity, reflecting the formation of a robust pupal exoskeleton and the upregulation of antimicrobial peptides as preparations for overwintering. One protein preferentially expressed in SD prepupae has a counterpart in Bombyx mori that functions as a diapause duration clock. The differentially expressed genes in LD prepupae included several members of the dusky and osiris families. We also observed the strong induction of different yellow‐like genes under SD and LD conditions which suggest a role in the developmental choice between seasonal phenotypes. Our transcriptomic data will facilitate the more detailed analysis of molecular mechanisms underlying seasonal polyphenism.
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Affiliation(s)
- Andreas Vilcinskas
- Institute for Insect Biotechnology Justus Liebig University Heinrich Buff Ring 26-32 35392 Giessen Germany
| | - Heiko Vogel
- Max-Planck Institute for Chemical Ecology Hans Knoell Strasse 8 07749 Jena Germany
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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.
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