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Jin J, Chen W, Xu C, Pooe OJ, Xie Y, Shen C, Meng M, Zhu Q, Zhang X, Liu X, Liu Y. Rational design and application of broad-spectrum antibodies for Bt Cry toxins determination. Anal Biochem 2024; 693:115584. [PMID: 38843975 DOI: 10.1016/j.ab.2024.115584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2024] [Revised: 05/25/2024] [Accepted: 06/03/2024] [Indexed: 06/18/2024]
Abstract
Using the amino acid sequences and analysis of selected known structures of Bt Cry toxins, Cry1Ab, Cry1Ac, Cry1Ah, Cry1B, Cry1C and Cry1F we specifically designed immunogens. After antibodies selection, broad-spectrum polyclonal antibodies (pAbs) and monoclonal antibody (namely 1A0-mAb) were obtained from rabbit and mouse, respectively. The produced pAbs displayed broad spectrum activity by recognizing Cry1 toxin, Cry2Aa, Cry2Ab and Cry3Aa with half maximal inhibitory concentration (IC50) values of 0.12-9.86 μg/mL. Similarly, 1A0-mAb showed broad spectrum activity, recognizing all of the above Cry protein (IC50 values of 4.66-20.46 μg/mL) with the exception of Cry2Aa. Using optimizations studies, 1A10-mAb was used as a capture antibody and pAbs as detection antibody. Double antibody sandwich enzyme-linked immunosorbent assays (DAS-ELISAs) were established for Cry1 toxin, Cry2Ab and Cry3Aa with the limit of detection (LOD) values of 2.36-36.37 ng/mL, respectively. The present DAS-ELISAs had good accuracy and precisions for the determination of Cry toxin spiked tap water, corn, rice, soybeans and soil samples. In conclusion, the present study has successfully obtained broad-spectrum pAbs and mAb. Furthermore, the generated pAbs- and mAb-based DAS-ELISAs protocol can potentially be used for the broad-spectrum monitoring of eight common subtypes of Bt Cry toxins residues in food and environmental samples.
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Affiliation(s)
- Jiafeng Jin
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, China; College of Plant Protection, Nanjing Agricultural University, Nanjing, 210023, China
| | - Wei Chen
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Chongxin Xu
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, China.
| | - Ofentse Jacob Pooe
- School of Life Sciences, University of KwaZulu-Natal, Durban, 4000, South Africa
| | - Yajing Xie
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Cheng Shen
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; College of Plant Protection, Nanjing Agricultural University, Nanjing, 210023, China
| | - Meng Meng
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; School of Life Sciences, Jiangsu University, Zhenjiang, 212013, China
| | - Qin Zhu
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Xiao Zhang
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Xianjin Liu
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Yuan Liu
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, China.
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Guo Z, Zhu L, Cheng Z, Dong L, Guo L, Bai Y, Wu Q, Wang S, Yang X, Xie W, Crickmore N, Zhou X, Lafont R, Zhang Y. A midgut transcriptional regulatory loop favors an insect host to withstand a bacterial pathogen. Innovation (N Y) 2024; 5:100675. [PMID: 39170942 PMCID: PMC11338098 DOI: 10.1016/j.xinn.2024.100675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Accepted: 07/09/2024] [Indexed: 08/23/2024] Open
Abstract
Mounting evidence suggests that insect hormones associated with growth and development also participate in pathogen defense. We have discovered a previously undescribed midgut transcriptional control pathway that modulates the availability of 20-hydroxyecdysone (20E) in a worldwide insect pest (Plutella xylostella), allowing it to defeat the major virulence factor of an insect pathogen Bacillus thuringiensis (Bt). A reduction of the transcriptional inhibitor (PxDfd) increases the expression of a midgut microRNA (miR-8545), which in turn represses the expression of a newly identified ecdysteroid-degrading glucose dehydrogenase (PxGLD). Downregulation of PxGLD reduces 20E degradation to increase 20E titer and concurrently triggers a transcriptional negative feedback loop to mitigate 20E overproduction. The moderately elevated 20E titer in the midgut activates a MAPK signaling pathway to increase Bt tolerance/resistance. These findings deepen our understanding of the functions attributed to these classical insect hormones and help inform potential future strategies that can be employed to control insect pests.
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Affiliation(s)
- Zhaojiang Guo
- State Key Laboratory of Vegetable Biobreeding, Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Liuhong Zhu
- State Key Laboratory of Vegetable Biobreeding, Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Zhouqiang Cheng
- State Key Laboratory of Vegetable Biobreeding, Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Lina Dong
- State Key Laboratory of Vegetable Biobreeding, Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Le Guo
- State Key Laboratory of Vegetable Biobreeding, Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yang Bai
- State Key Laboratory of Vegetable Biobreeding, Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Qingjun Wu
- State Key Laboratory of Vegetable Biobreeding, Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Shaoli Wang
- State Key Laboratory of Vegetable Biobreeding, Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Xin Yang
- State Key Laboratory of Vegetable Biobreeding, Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Wen Xie
- State Key Laboratory of Vegetable Biobreeding, Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Neil Crickmore
- School of Life Sciences, University of Sussex, Brighton BN1 9QE, UK
| | - Xuguo Zhou
- Department of Entomology, School of Integrative Biology, College of Liberal Arts & Sciences, University of Illinois Urbana-Champaign, Urbana, IL 61801-3795, USA
| | - René Lafont
- Sorbonne Université, CNRS - IBPS (BIOSIPE), 75005 Paris, France
| | - Youjun Zhang
- State Key Laboratory of Vegetable Biobreeding, Department of Plant Protection, Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
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Duan Y, Yao X, Li P, Zhao Y, Zhang B, An S, Wei J, Li X. Death-Associated LIM-Only Protein Reduces Cry1Ac Toxicity by Sequestration of Cry1Ac Protoxin and Activated Toxin in Helicoverpa armigera. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:18708-18719. [PMID: 39106049 DOI: 10.1021/acs.jafc.4c04657] [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: 08/07/2024]
Abstract
The extensive use of Bacillus thuringiensis (Bt) in pest management has driven the evolution of pest resistance to Bt toxins, particularly Cry1Ac. Effective management of Bt resistance necessitates a good understanding of which pest proteins interact with Bt toxins. In this study, we screened a Helicoverpa armigera larval midgut cDNA library and captured 208 potential Cry1Ac-interacting proteins. Among these, we further examined the interaction between Cry1Ac and a previously unknown Cry1Ac-interacting protein, HaDALP (H. armigera death-associated LIM-only protein), as well as its role in toxicology. The results revealed that HaDALP specifically binds to both the Cry1Ac protoxin and activated toxin, significantly enhancing cell and larval tolerance to Cry1Ac. Additionally, HaDALP was overexpressed in a Cry1Ac-resistant H. armigera strain. These findings reveal a greater number of Cry1Ac-interacting proteins than previously known and demonstrate, for the first time, that HaDALP reduces Cry1Ac toxicity by sequestering both the protoxin and activated toxin.
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Affiliation(s)
- Yunpeng Duan
- Henan International Laboratory for Green Pest Control/College of Plant Protection, Henan Agricultural University, Zhengzhou 450046, China
| | - Xue Yao
- Henan International Laboratory for Green Pest Control/College of Plant Protection, Henan Agricultural University, Zhengzhou 450046, China
| | - Pin Li
- Henan International Laboratory for Green Pest Control/College of Plant Protection, Henan Agricultural University, Zhengzhou 450046, China
| | - Yuge Zhao
- Henan International Laboratory for Green Pest Control/College of Plant Protection, Henan Agricultural University, Zhengzhou 450046, China
| | - Bo Zhang
- Henan International Laboratory for Green Pest Control/College of Plant Protection, Henan Agricultural University, Zhengzhou 450046, China
| | - Shiheng An
- Henan International Laboratory for Green Pest Control/College of Plant Protection, Henan Agricultural University, Zhengzhou 450046, China
| | - Jizhen Wei
- Henan International Laboratory for Green Pest Control/College of Plant Protection, Henan Agricultural University, Zhengzhou 450046, China
| | - Xianchun Li
- Department of Entomology and BIO5 Institute, University of Arizona, Tucson, Arizona 85721, United States
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Wu W, Ali A, Shen J, Ren M, Cai Y, He L. Cell Penetrating Peptide Enhances the Aphidicidal Activity of Spider Venom-Derived Neurotoxin. Toxins (Basel) 2024; 16:358. [PMID: 39195768 PMCID: PMC11360749 DOI: 10.3390/toxins16080358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2024] [Revised: 08/08/2024] [Accepted: 08/12/2024] [Indexed: 08/29/2024] Open
Abstract
HxTx-Hv1h, a neurotoxic peptide derived from spider venom, has been developed for use in commercial biopesticide formulations. Cell Penetrating Peptides (CPPs) are short peptides that facilitate the translocation of various biomolecules across cellular membranes. Here, we evaluated the aphidicidal efficacy of a conjugated peptide, HxTx-Hv1h/CPP-1838, created by fusing HxTx-Hv1h with CPP-1838. Additionally, we aimed to establish a robust recombinant expression system for HxTx-Hv1h/CPP-1838. We successfully achieved the secretory production of HxTx-Hv1h, its fusion with Galanthus nivalis agglutinin (GNA) forming HxTx-Hv1h/GNA and HxTx-Hv1h/CPP-1838 in yeast. Purified HxTx-Hv1h exhibited contact toxicity against Megoura crassicauda, with a 48 h median lethal concentration (LC50) of 860.5 μg/mL. Fusion with GNA or CPP-1838 significantly enhanced its aphidicidal potency, reducing the LC50 to 683.5 μg/mL and 465.2 μg/mL, respectively. The aphidicidal efficacy was further improved with the addition of surfactant, decreasing the LC50 of HxTx-Hv1h/CPP-1838 to 66.7 μg/mL-over four times lower compared to HxTx-Hv1h alone. Furthermore, we engineered HxTx-Hv1h/CPP-1838 multi-copy expression vectors utilizing the BglBrick assembly method and achieved high-level recombinant production in laboratory-scale fermentation. This study is the first to document a CPP fusion strategy that enhances the transdermal aphidicidal activity of a natural toxin like HxTx-Hv1h and opens up the possibility of exploring the recombinant production of HxTx-Hv1h/CPP-1838 for potential applications.
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Affiliation(s)
- Wenxian Wu
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu Agricultural Science and Technology Center, Chengdu 610000, China; (W.W.); (M.R.)
| | - Abid Ali
- Department of Entomology, University of Agriculture Faisalabad, Faisalabad 38040, Pakistan;
- College of Life Science, Shenyang Normal University, Shenyang 110034, China
| | - Jinbo Shen
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou 310000, China;
| | - Maozhi Ren
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu Agricultural Science and Technology Center, Chengdu 610000, China; (W.W.); (M.R.)
| | - Yi Cai
- College of Life Science, Sichuan Agricultural University, Ya’an 625000, China
| | - Limei He
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu Agricultural Science and Technology Center, Chengdu 610000, China; (W.W.); (M.R.)
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Lázaro-Berenguer M, Ferré J, Hernández-Martínez P. Receptor interactions of protoxin and activated Vip3Aa structural conformations in Spodoptera exigua. PEST MANAGEMENT SCIENCE 2024. [PMID: 39123331 DOI: 10.1002/ps.8341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2024] [Revised: 07/12/2024] [Accepted: 07/16/2024] [Indexed: 08/12/2024]
Abstract
BACKGROUND The Vip3Aa insecticidal protein, produced by Bacillus thuringiensis, has been effectively used in commercial Bt-crops to manage lepidopteran pests. Upon ingestion by larvae, the protoxin is processed by midgut proteases into the activated protein and binds specifically to its receptors in the midgut, leading to insect mortality. Cryo-EM resolution of the trypsin-processed Vip3Aa protein unveiled structural remodelling of the N-terminal region during the transition from protoxin to activated protein. This conformational change has been demonstrated to be crucial for toxicity against Spodoptera exigua larvae, a major global lepidopteran pest. In this study, we investigated the relevance of the structural remodelling for the specific binding to midgut receptors. RESULTS We conducted in vitro binding assays with radiolabelled proteins and brush border membrane vesicles (BBMV) from S. exigua, employing structural mutants that lock the protein in either its protoxin or its activated conformation. Our results indicate that both structural stages of the protein share binding sites in the midgut epithelium. Moreover, in vivo competition assays revealed that Vip3Aa is able to bind to functional receptors in S. exigua larvae both as protoxin and as activated protein. CONCLUSION Altogether, our findings point to both structural conformations contributing to receptor binding. In vivo, either spontaneous structural shift upon proteolytic cleavage or receptor-mediated remodelling could be occurring. However, the timing and context in which the conformational change occurs could influence membrane insertion and toxicity. Our results show the complex interplay between proteolytic processing, protein structure and receptor interactions in Vip3Aa's toxicity. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Maria Lázaro-Berenguer
- Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, Burjassot, Spain
| | - Juan Ferré
- Institute of Biotechnology and Biomedicine (BIOTECMED), Universitat de València, Burjassot, Spain
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6
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Jiang K, Gao X. Current advances on Vip3 highlight the promising potential of bacterial insecticidal proteins. Trends Microbiol 2024; 32:732-735. [PMID: 38902178 DOI: 10.1016/j.tim.2024.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 06/03/2024] [Accepted: 06/04/2024] [Indexed: 06/22/2024]
Abstract
Biological control, based on microbial insecticidal proteins, has become an important strategy for sustainable pest management. This forum discusses recent advancements and research strategies of the bacterial insecticidal protein vegetative insecticidal protein 3 (Vip3), aiming to provide valuable insights for future investigations on Vip3 and other insecticidal proteins.
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Affiliation(s)
- Kun Jiang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China.
| | - Xiang Gao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China.
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7
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Babar TK, Glare TR, Hampton JG, Hurst MRH, Narciso J. Biochemical characterisation and production kinetics of high molecular-weight (HMW) putative antibacterial proteins of insect pathogenic Brevibacillus laterosporus isolates. BMC Microbiol 2024; 24:259. [PMID: 38997685 PMCID: PMC11245835 DOI: 10.1186/s12866-024-03340-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 05/16/2024] [Indexed: 07/14/2024] Open
Abstract
BACKGROUND Bacterial genomes often encode structures similar to phage capsids (encapsulins) and phage tails which can be induced spontaneously or using genotoxic compounds such as mitomycin C. These high molecular-weight (HMW) putative antibacterial proteins (ABPs) are used against the competitive strains under natural environment. Previously, it was unknown whether these HMW putative ABPs originating from the insect pathogenic Gram-positive, spore-forming bacterium Brevibacillus laterosporus (Bl) isolates (1821L, 1951) are spontaneously induced during the growth and pose a detrimental effect on their own survival. Furthermore, no prior work has been undertaken to determine their biochemical characteristics. RESULTS Using a soft agar overlay method with polyethylene glycol precipitation, a narrow spectrum of bioactivity was found from the precipitated lysate of Bl 1951. Electron micrographs of mitomycin C- induced filtrates showed structures similar to phage capsids and contractile tails. Bioactivity assays of cell free supernatants (CFS) extracted during the growth of Bl 1821L and Bl 1951 suggested spontaneous induction of these HMW putative ABPs with an autocidal activity. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis of spontaneously induced putative ABPs showed appearance of ~ 30 kDa and ~ 48 kDa bands of varying intensity across all the time intervals during the bacterial growth except in the initial hours. Statistically, spontaneously induced HMW putative ABPs of Bl 1951 exhibited a significant decrease in the number of viable cells of its producer strain after 18 h of growth in liquid. In addition, a significant change in pH and prominent bioactivity of the CFS of this particular time period was noted. Biochemically, the filtered supernatant derived from either Bl 1821L or Bl 1951 maintained bioactivity over a wide range of pH and temperature. CONCLUSION This study reports the spontaneous induction of HMW putative ABPs (bacteriocins) of Bl 1821L and Bl 1951 isolates during the course of growth with potential autocidal activity which is critically important during production as a potential biopesticide. A narrow spectrum of putative antibacterial activity of Bl 1951 precipitate was found. The stability of HMW putative ABPs of Bl 1821L and Bl 1951 over a wide range of pH and temperature can be useful in expanding the potential of this useful bacterium beyond the insecticidal value.
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Affiliation(s)
- Tauseef K Babar
- Bioprotection Research Centre, Lincoln University, Lincoln, Canterbury, 7647, New Zealand.
- Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, 60000, Pakistan.
| | - Travis R Glare
- Bioprotection Research Centre, Lincoln University, Lincoln, Canterbury, 7647, New Zealand
- Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln, Canterbury, 7647, New Zealand
| | - John G Hampton
- Bioprotection Research Centre, Lincoln University, Lincoln, Canterbury, 7647, New Zealand
- Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln, Canterbury, 7647, New Zealand
| | - Mark R H Hurst
- Resilient agriculture, AgResearch, Lincoln Research Centre, Christchurch, New Zealand
| | - Josefina Narciso
- Bioprotection Research Centre, Lincoln University, Lincoln, Canterbury, 7647, New Zealand
- Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln, Canterbury, 7647, New Zealand
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Xiao H, Ma C, Peng R, Xie M. Insights into the role of non-coding RNAs in the development of insecticide resistance in insects. Front Genet 2024; 15:1429411. [PMID: 39036703 PMCID: PMC11257933 DOI: 10.3389/fgene.2024.1429411] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Accepted: 06/10/2024] [Indexed: 07/23/2024] Open
Abstract
Pest control heavily relies on chemical pesticides has been going on for decades. However, the indiscriminate use of chemical pesticides often results in the development of resistance in pests. Almost all pests have developed some degree of resistance to pesticides. Research showed that the mechanisms of insecticide resistance in insects encompass metabolic resistance, behavioral resistance, penetration resistance and target-site resistance. Research on the these mechanisms has been mainly focused on the cis-regulatory or trans-regulatory for the insecticide resistance-related genes, with less attention paid to non-coding RNAs (ncRNAs), such as microRNA (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA). There has been increased studies focus on understanding how these ncRNAs are involved in post-transcriptional regulation of insecticide resistance-related genes. Besides, the formatted endogenous RNA (ceRNA) regulatory networks (lncRNA/circRNA-miRNA-mRNA) has been identified as a key player in governing insect resistance formation. This review delves into the functions and underlying mechanisms of miRNA, lncRNA, and circRNA in regulating insect resistance. ncRNAs orchestrate insect resistance by modulating the expression of detoxification enzyme genes, insecticide target genes, as well as receptor genes, effectively regulating both target-site, metabolic and penetration resistance in insects. It also explores the regulatory mechanisms of ceRNA networks in the development of resistance. By enhancing our understanding of the mechanisms of ncRNAs in insecticide resistance, it will not only provide valuable insights into the new mechanisms of insecticide resistance but also help to enrich new directions in ncRNAs gene regulation research.
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Affiliation(s)
- Huamei Xiao
- Key Laboratory of Crop Growth and Development Regulation of Jiangxi Province, College of Life Sciences and Resource Environment, Yichun University, Yichun, China
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Wang L, Xu M, He L, Wei W, Xu D, Cong S, Liu K, Wan P. Mutation in PgABCC2 confers low-level resistance to Cry1Ac in pink bollworm. PEST MANAGEMENT SCIENCE 2024; 80:3326-3333. [PMID: 38380740 DOI: 10.1002/ps.8036] [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: 12/15/2023] [Revised: 02/16/2024] [Accepted: 02/19/2024] [Indexed: 02/22/2024]
Abstract
BACKGROUND With the increasing incidence of pest resistance to transgenic crops producing Bacillus thuringiensis (Bt) proteins in the field, elucidating the molecular basis of resistance is important for monitoring, delaying and countering pest resistance. Previous work revealed that mutation or down-regulated expression of the cadherin gene (PgCad1) is associated with pink bollworm (Pectinophora gossypiella) resistance to Cry1Ac, and 20 mutant PgCad1 alleles (r1-r20) were characterized. Here, we tested the hypothesis that the ABC transporter PgABCC2 is a functional receptor for the Bt toxin Cry1Ac and that a mutation is associated with resistance. RESULTS We identified and characterized the first resistance allele (rC2) of PgABCC2 in the laboratory-selected Cry1Ac-resistant strain AQ-C2 of pink bollworm. The rC2 allele had a one-base deletion in exon20, resulting in a frameshift and the introduction of a premature stop codon. This resulting PgABCC2 protein had a truncated C-terminus, including the loss of the NBD2 domain. AQ-C2 exhibited 20.2-fold greater resistance to Cry1Ac than the susceptible strain, and its inheritance of Cry1Ac resistance was recessive and genetically linked to PgABCC2. When produced in cultured insect cells, recombinant wild-type and rC2 mutant PgABCC2 proteins localized within the cell plasma membrane, although substantial cytoplasmic retention was also observed for the mutant protein, while the mutant PgABCC2 caused a 13.9-fold decrease in Cry1Ac toxicity versus the wild-type PgABCC2. CONCLUSIONS PgABCC2 is a functional receptor of Cry1Ac and the loss of its carboxyl terminus (including its NBD2 domain) confers low-level resistance to Cry1Ac in both larvae and in cultured cells. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Ling Wang
- Key Laboratory of Integrated Pest Management on Crops in Central China, Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Crop Disease, Insect Pests and Weeds Control, Institute of Plant Protection and Soil Science, Hubei Academy of Agricultural Sciences, Wuhan, China
| | - Min Xu
- School of Life Sciences, Central China Normal University, Wuhan, China
| | - Lu He
- School of Life Sciences, Central China Normal University, Wuhan, China
| | - Wei Wei
- Applied Biotechnology Center, Wuhan University of Bioengineering, Wuhan, China
| | - Dong Xu
- Key Laboratory of Integrated Pest Management on Crops in Central China, Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Crop Disease, Insect Pests and Weeds Control, Institute of Plant Protection and Soil Science, Hubei Academy of Agricultural Sciences, Wuhan, China
| | - Shengbo Cong
- Key Laboratory of Integrated Pest Management on Crops in Central China, Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Crop Disease, Insect Pests and Weeds Control, Institute of Plant Protection and Soil Science, Hubei Academy of Agricultural Sciences, Wuhan, China
| | - Kaiyu Liu
- School of Life Sciences, Central China Normal University, Wuhan, China
| | - Peng Wan
- Key Laboratory of Integrated Pest Management on Crops in Central China, Ministry of Agriculture and Rural Affairs, Hubei Key Laboratory of Crop Disease, Insect Pests and Weeds Control, Institute of Plant Protection and Soil Science, Hubei Academy of Agricultural Sciences, Wuhan, China
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10
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Berini F, Montali A, Liguori R, Venturini G, Bonelli M, Shaltiel-Harpaz L, Reguzzoni M, Siti M, Marinelli F, Casartelli M, Tettamanti G. Production and characterization of Trichoderma asperellum chitinases and their use in synergy with Bacillus thuringiensis for lepidopteran control. PEST MANAGEMENT SCIENCE 2024; 80:3401-3411. [PMID: 38407453 DOI: 10.1002/ps.8045] [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: 09/06/2023] [Revised: 02/19/2024] [Accepted: 02/21/2024] [Indexed: 02/27/2024]
Abstract
BACKGROUND Despite their known negative effects on ecosystems and human health, synthetic pesticides are still largely used to control crop insect pests. Currently, the biopesticide market for insect biocontrol mainly relies on the entomopathogenic bacterium Bacillus thuringiensis (Bt). New biocontrol tools for crop protection might derive from fungi, in particular from Trichoderma spp., which are known producers of chitinases and other bioactive compounds able to negatively affect insect survival. RESULTS In this study, we first developed an environmentally sustainable production process for obtaining chitinases from Trichoderma asperellum ICC012. Then, we investigated the biological effects of this chitinase preparation - alone or in combination with a Bt-based product - when orally administered to two lepidopteran species. Our results demonstrate that T. asperellum efficiently produces a multi-enzymatic cocktail able to alter the chitin microfibril network of the insect peritrophic matrix, resulting in delayed development and larval death. The co-administration of T. asperellum chitinases and sublethal concentrations of Bt toxins increased larval mortality. This synergistic effect was likely due to the higher amount of Bt toxins that passed the damaged peritrophic matrix and reached the target receptors on the midgut cells of chitinase-treated insects. CONCLUSION Our findings may contribute to the development of an integrated pest management technology based on fungal chitinases that increase the efficacy of Bt-based products, mitigating the risk of Bt-resistance development. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Francesca Berini
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
- Interuniversity Centre for Studies on Bioinspired Agro-Environmental Technology (BAT Centre), University of Naples Federico II, Portici, Italy
| | - Aurora Montali
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
| | - Riccardo Liguori
- Isagro Research Centre affiliated to Gowan Crop Protection Ltd, Novara, Italy
| | - Giovanni Venturini
- Isagro Research Centre affiliated to Gowan Crop Protection Ltd, Novara, Italy
| | - Marco Bonelli
- Department of Biosciences, University of Milan, Milan, Italy
| | - Liora Shaltiel-Harpaz
- Integrated Pest Management Laboratory Northern R&D, MIGAL - Galilee Research Institute, Kiryat Shmona, Israel
- Environmental Sciences Department, Faculty of Sciences and Technology, Tel Hai College, Kiryat Shmona, Israel
| | - Marcella Reguzzoni
- Department of Medicine and Technological Innovation, University of Insubria, Varese, Italy
| | - Moran Siti
- Luxembourg Industries Ltd, Tel-Aviv, Israel
| | - Flavia Marinelli
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
- Interuniversity Centre for Studies on Bioinspired Agro-Environmental Technology (BAT Centre), University of Naples Federico II, Portici, Italy
| | - Morena Casartelli
- Interuniversity Centre for Studies on Bioinspired Agro-Environmental Technology (BAT Centre), University of Naples Federico II, Portici, Italy
- Department of Biosciences, University of Milan, Milan, Italy
| | - Gianluca Tettamanti
- Department of Biotechnology and Life Sciences, University of Insubria, Varese, Italy
- Interuniversity Centre for Studies on Bioinspired Agro-Environmental Technology (BAT Centre), University of Naples Federico II, Portici, Italy
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11
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Liu Z, Liao C, Zou L, Jin M, Shan Y, Quan Y, Yao H, Zhang L, Wang P, Liu Z, Wang N, Li A, Liu K, Tabashnik BE, Heckel DG, Wu K, Xiao Y. Retrotransposon-mediated disruption of a chitin synthase gene confers insect resistance to Bacillus thuringiensis Vip3Aa toxin. PLoS Biol 2024; 22:e3002704. [PMID: 38954724 PMCID: PMC11249258 DOI: 10.1371/journal.pbio.3002704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 07/15/2024] [Accepted: 06/07/2024] [Indexed: 07/04/2024] Open
Abstract
The vegetative insecticidal protein Vip3Aa from Bacillus thuringiensis (Bt) has been produced by transgenic crops to counter pest resistance to the widely used crystalline (Cry) insecticidal proteins from Bt. To proactively manage pest resistance, there is an urgent need to better understand the genetic basis of resistance to Vip3Aa, which has been largely unknown. We discovered that retrotransposon-mediated alternative splicing of a midgut-specific chitin synthase gene was associated with 5,560-fold resistance to Vip3Aa in a laboratory-selected strain of the fall armyworm, a globally important crop pest. The same mutation in this gene was also detected in a field population. Knockout of this gene via CRISPR/Cas9 caused high levels of resistance to Vip3Aa in fall armyworm and 2 other lepidopteran pests. The insights provided by these results could help to advance monitoring and management of pest resistance to Vip3Aa.
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Affiliation(s)
- Zhenxing Liu
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Chongyu Liao
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Luming Zou
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Minghui Jin
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Yinxue Shan
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Yudong Quan
- The State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, West Yuanmingyuan Road, Beijing, China
| | - Hui Yao
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Lei Zhang
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Peng Wang
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Zhuangzhuang Liu
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Na Wang
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Anjing Li
- Institute of Entomology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Kaiyu Liu
- Institute of Entomology, School of Life Sciences, Central China Normal University, Wuhan, China
| | - Bruce E. Tabashnik
- Department of Entomology, University of Arizona, Tucson, Arizona, United States of America
| | - David G. Heckel
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
- Department of Entomology, Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Kongming Wu
- The State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, West Yuanmingyuan Road, Beijing, China
| | - Yutao Xiao
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
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12
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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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13
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Jiménez J, Mishra R, Wang X, Magee CM, Bonning BC. Composition and abundance of midgut plasma membrane proteins in two major hemipteran vectors of plant viruses, Bemisia tabaci and Myzus persicae. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2024; 116:e22133. [PMID: 39054788 DOI: 10.1002/arch.22133] [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: 04/25/2024] [Revised: 06/13/2024] [Accepted: 06/29/2024] [Indexed: 07/27/2024]
Abstract
Multiple species within the order Hemiptera cause severe agricultural losses on a global scale. Aphids and whiteflies are of particular importance due to their role as vectors for hundreds of plant viruses, many of which enter the insect via the gut. To facilitate the identification of novel targets for disruption of plant virus transmission, we compared the relative abundance and composition of the gut plasma membrane proteomes of adult Bemisia tabaci (Hemiptera: Aleyrodidae) and Myzus persicae (Hemiptera: Aphididae), representing the first study comparing the gut plasma membrane proteomes of two different insect species. Brush border membrane vesicles were prepared from dissected guts, and proteins extracted, identified and quantified from triplicate samples via timsTOF mass spectrometry. A total of 1699 B. tabaci and 1175 M. persicae proteins were identified. Following bioinformatics analysis and manual curation, 151 B. tabaci and 115 M. persicae proteins were predicted to localize to the plasma membrane of the gut microvilli. These proteins were further categorized based on molecular function and biological process according to Gene Ontology terms. The most abundant gut plasma membrane proteins were identified. The ten plasma membrane proteins that differed in abundance between the two insect species were associated with the terms "protein binding" and "viral processes." In addition to providing insight into the gut physiology of hemipteran insects, these gut plasma membrane proteomes provide context for appropriate identification of plant virus receptors based on a combination of bioinformatic prediction and protein localization on the surface of the insect gut.
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Affiliation(s)
- Jaime Jiménez
- Department of Entomology and Nematology, University of Florida, Gainesville, Florida, USA
| | - Ruchir Mishra
- Department of Entomology and Nematology, University of Florida, Gainesville, Florida, USA
| | - Xinyue Wang
- Department of Entomology and Nematology, University of Florida, Gainesville, Florida, USA
| | - Ciara M Magee
- Department of Entomology and Nematology, University of Florida, Gainesville, Florida, USA
| | - Bryony C Bonning
- Department of Entomology and Nematology, University of Florida, Gainesville, Florida, USA
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14
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Wang C, Zhang Y, Guan F, He YZ, Wu Y. Genome-wide identification and phylogenetic analysis of the tetraspanin gene family in lepidopteran insects and expression profiling analysis in Helicoverpa armigera. INSECT SCIENCE 2024. [PMID: 38880966 DOI: 10.1111/1744-7917.13402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 05/01/2024] [Accepted: 05/16/2024] [Indexed: 06/18/2024]
Abstract
The tetraspanin gene family encodes cell-surface proteins that span the membrane 4 times and play critical roles in a wide range of biological processes across numerous organisms. Recent findings highlight the involvement of a tetraspanin of the lepidopteran pest Helicoverpa armigera in resistance to Bacillus thuringiensis Cry insecticidal proteins, which are extensively used in transgenic crops. Thus, a better understanding of lepidopteran tetraspanins is urgently needed. In the current study, genome scanning in 10 lepidopteran species identified a total of 283 sequences encoding potential tetraspanins. Based on conserved cysteine patterns in the large extracellular loop and their phylogenetic relationships, these tetraspanins were classified into 8 subfamilies (TspA to TspH). Six ancestral introns were identified within lepidopteran tetraspanin genes. Tetraspanins in TspA, TspB, TspC, and TspD subfamilies exhibit highly similar gene organization, while tetraspanins in the remaining 4 subfamilies exhibited variation in intron loss and/or gain during evolution. Analysis of chromosomal distribution revealed a lepidopteran-specific cluster of 10 to 11 tetraspanins, likely formed by tandem duplication events. Selective pressure analysis indicated negative selection across all orthologous groups, with ω values ranging between 0.004 and 0.362. However, positive selection was identified at 18 sites within TspB5, TspC5, TspE3, and TspF10. Furthermore, spatiotemporal expression analysis of H. armigera tetraspanins demonstrated variable expression levels across different developmental stages and tissues, suggesting diverse functions of tetraspanin members in this globally important insect pest. Our findings establish a solid foundation for subsequent functional investigations of tetraspanins in lepidopteran species.
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Affiliation(s)
- Chenyang Wang
- College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yinuo Zhang
- College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Fang Guan
- College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Ya-Zhou He
- College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yidong Wu
- College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
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15
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De Bortoli CP, Polanczyk RA, Crickmore N. Throwing Brazilian strains into the melting pot of P. xylostella resistance to Bacillus thuringiensis. J Invertebr Pathol 2024; 204:108101. [PMID: 38574951 DOI: 10.1016/j.jip.2024.108101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 03/25/2024] [Accepted: 04/01/2024] [Indexed: 04/06/2024]
Abstract
The resistance of pest insects to biopesticides based on the bacterium Bacillus thuringiensis (Bt) is normally associated with changes to the receptors involved in the mechanism of action of the pesticidal proteins produced by Bt. In some strains of Plutella xylostella (the diamondback moth) resistance has evolved through a signalling mechanism in which the genes encoding the receptor proteins are downregulated whereas in others it has been linked to structural changes in the receptors themselves. One such well characterized mutation is in the ABCC2 gene indicating that changes to this protein can result in resistance. However other studies have found that knocking out this protein does not result in a significant level of resistance. In this study we wanted to test the hypothesis that constitutive receptor downregulation is the major cause of Bt resistance in P. xylostella and that mutations in the now poorly expressed receptor genes may not contribute significantly to the phenotype. To that end we investigated the expression of a receptor (ABCC2) and the major regulator of the signalling pathway (MAP4K4) in two resistant and four susceptible strains. No correlation was found between expression levels and susceptibility; however, a frameshift mutation was identified in the ABCC2 receptor in a newly characterized resistant strain.
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Affiliation(s)
- Caroline Placidi De Bortoli
- School of Life Sciences, University of Sussex, Brighton, UK; Faculty of Agricultural and Veterinary Sciences, Paulista State University "Júlio de Mesquita Filho", Jaboticabal Campus, SP, Brazil
| | - Ricardo Antonio Polanczyk
- Faculty of Agricultural and Veterinary Sciences, Paulista State University "Júlio de Mesquita Filho", Jaboticabal Campus, SP, Brazil
| | - Neil Crickmore
- School of Life Sciences, University of Sussex, Brighton, UK.
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16
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Amezian D, Nauen R, Van Leeuwen T. The role of ATP-binding cassette transporters in arthropod pesticide toxicity and resistance. CURRENT OPINION IN INSECT SCIENCE 2024; 63:101200. [PMID: 38641174 DOI: 10.1016/j.cois.2024.101200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 03/10/2024] [Accepted: 04/07/2024] [Indexed: 04/21/2024]
Abstract
Pesticide resistance in arthropods threatens agricultural productivity and the control of vector-borne diseases. The ATP-binding cassette (ABC) transporters have emerged as important factors in the toxicity of synthetic pesticides, as well as for Bacillus thuringiensis insecticidal Cry protein binding. Depending on the localization of expression, both higher and lower expression of ABCs have been linked with pesticide resistance. The recent development of genetic-based approaches such as RNAi and CRISPR/Cas9 gene editing in nonmodel species, has greatly contributed to unveil their functional importance in pesticide toxicity and resistance. Using these tools, we are now poised to further unravel the molecular genetic mechanisms of gene regulation uncovering more elusive regulatory resistance genes.
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Affiliation(s)
- Dries Amezian
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Ralf Nauen
- Bayer AG, Crop Science Division, R&D, Alfred Nobel-Strasse 50, 40789 Monheim, Germany
| | - Thomas Van Leeuwen
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium.
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17
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Niu X, Jiang J, Sun Y, Hull JJ, Ma W, Hua H, Lin Y. Knockdown of MAPK p38-linked genes increases the susceptibility of Chilo suppressalis larvae to various transgenic Bt rice lines. Int J Biol Macromol 2024; 266:130815. [PMID: 38537847 DOI: 10.1016/j.ijbiomac.2024.130815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/11/2024] [Accepted: 03/10/2024] [Indexed: 04/01/2024]
Abstract
Bacillus thuringiensis (Bt) toxins have provided exceptional control of agricultural insect pests, however, over reliance on the proteins would potentially contribute to the development of field tolerance. Developing new sustainable insect pest control methods that target the mechanisms underlying Bt tolerance can potentially support the Bt control paradigm while also providing insights into basic insect physiology. The MAPK p38 pathway is strongly associated with Bt tolerance in Chilo suppressalis, a major pest of rice. To gain insights into how this pathway impacts tolerance, high-throughput screening of C. suppressalis larval midguts initially identified eight novel target genes. Increased larval sensitivity to the transgenic cry1Ca rice strain T1C-19 was observed following RNA interference-mediated knockdown of four of the genes, Cscnc, Csgcp, Cszfp26 and CsZMYM1. Similar enhanced sensitivity to the TT51 (expressing Cry1Ab/1Ac) and T2A-1 (expressing Cry2Aa) transgenic rice lines occurred when Cszfp26 and CsZMYM1 were knocked down. All four target genes are downstream of the MAPK p38 pathway but do not participate in negative feedback loop of the pathway. These results implicate Cscnc, Csgcp, Cszfp and CsZMYM1 in the C. suppressalis transgenic cry1Ca rice tolerance mechanism regulated by MAPK p38. These findings further enhance our understanding of the MAPK p38-dependent molecular mechanisms underlying Bt tolerance in C. suppressalis and open new avenues of tolerance management to develop.
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Affiliation(s)
- Xurong Niu
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Hubei Hongshan Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China; Pest Management and Biocontrol Research Unit, US Arid Land Agricultural Research Center, USDA Agricultural Research Services, Maricopa, AZ 85138, United States
| | - Jialiang Jiang
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Hubei Hongshan Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China; Pest Management and Biocontrol Research Unit, US Arid Land Agricultural Research Center, USDA Agricultural Research Services, Maricopa, AZ 85138, United States
| | - Yajie Sun
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Hubei Hongshan Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China; Pest Management and Biocontrol Research Unit, US Arid Land Agricultural Research Center, USDA Agricultural Research Services, Maricopa, AZ 85138, United States
| | - J Joe Hull
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Hubei Hongshan Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China; Pest Management and Biocontrol Research Unit, US Arid Land Agricultural Research Center, USDA Agricultural Research Services, Maricopa, AZ 85138, United States
| | - Weihua Ma
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Hubei Hongshan Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China; Pest Management and Biocontrol Research Unit, US Arid Land Agricultural Research Center, USDA Agricultural Research Services, Maricopa, AZ 85138, United States
| | - Hongxia Hua
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Hubei Hongshan Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China; Pest Management and Biocontrol Research Unit, US Arid Land Agricultural Research Center, USDA Agricultural Research Services, Maricopa, AZ 85138, United States
| | - Yongjun Lin
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Hubei Hongshan Laboratory, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China; Pest Management and Biocontrol Research Unit, US Arid Land Agricultural Research Center, USDA Agricultural Research Services, Maricopa, AZ 85138, United States
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18
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Liu L, He W, Xu P, Wei W, Wang J, Liu K. Contribution of the transcription factor SfGATAe to Bt Cry toxin resistance in Spodoptera frugiperda through reduction of ABCC2 expression. Int J Biol Macromol 2024; 267:131459. [PMID: 38593893 DOI: 10.1016/j.ijbiomac.2024.131459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 03/27/2024] [Accepted: 04/06/2024] [Indexed: 04/11/2024]
Abstract
Insect resistance evolution poses a significant threat to the advantages of biopesticides and transgenic crops utilizing insecticidal Cry-toxins from Bacillus thuringiensis (Bt). However, there is limited research on the relationship between transcriptional regulation of specific toxin receptors in lepidopteran insects and their resistance to Bt toxins. Here, we report the positive regulatory role of the SfGATAe transcription factor on the expression of the ABCC2 gene in Spodoptera frugiperda. DNA regions in the SfABCC2 promoter that are vital for regulation by SfGATAe, utilizing DAP-seq technology and promoter deletion mapping. Through yeast one-hybrid assays, DNA pull-down experiments, and site-directed mutagenesis, we confirmed that the transcription factor SfGATAe regulates the core control site PBS2 in the ABCC2 target gene. Tissue-specific expression analysis has revealed that SfGATAe is involved in the regulation and expression of midgut cells in the fall armyworm. Silencing SfGATAe in fall armyworm larvae resulted in reduced expression of SfABCC2 and decreased sensitivity to Cry1Ac toxin. Overall, this study elucidated the regulatory mechanism of the transcription factor SfGATAe on the expression of the toxin receptor gene SfABCC2 and this transcriptional control mechanism impacts the resistance of the fall armyworm to Bt toxins.
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Affiliation(s)
- Leilei Liu
- Center of Applied Biotechnology, School of Life Sciences and Technology, Wuhan University of Bioengineering, Wuhan, Hubei, China.
| | - Wenfeng He
- Center of Applied Biotechnology, School of Life Sciences and Technology, Wuhan University of Bioengineering, Wuhan, Hubei, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Peiwen Xu
- Center of Applied Biotechnology, School of Life Sciences and Technology, Wuhan University of Bioengineering, Wuhan, Hubei, China; College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Wei Wei
- Center of Applied Biotechnology, School of Life Sciences and Technology, Wuhan University of Bioengineering, Wuhan, Hubei, China
| | - Jintao Wang
- Center of Applied Biotechnology, School of Life Sciences and Technology, Wuhan University of Bioengineering, Wuhan, Hubei, China
| | - Kaiyu Liu
- School of Life Sciences, Central China Normal University, Wuhan, Hubei, China
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19
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Pan X, Cao F, Guo X, Wang Y, Cui Z, Huang T, Hou Y, Guan X. Development of a Safe and Effective Bacillus thuringiensis-Based Nanobiopesticide for Controlling Tea Pests. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:7807-7817. [PMID: 38514390 DOI: 10.1021/acs.jafc.4c00833] [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: 03/23/2024]
Abstract
Mg(OH)2 was used as the nanocarrier of the Bacillus thuringiensis (Bt) Cry1Ac protein, and the synthesized Cry1Ac-Mg(OH)2 composites were regular and uniform nanosheets. Nano-Mg(OH)2 could effectively improve the insecticidal effect of the Cry1Ac protein toward Ectropis obliqua. It could enhance the damage degree of the Cry1Ac protein to intestinal epithelial cells and microvilli, induce and enrich the production of reactive oxygen species (ROS) in the midgut, and enhance the degradation of the Cry1Ac protein into active fragments. Furthermore, an anti-rinsing assay showed that the Cry1Ac-Mg(OH)2 composites were bound to the notch structure of the tea leaf surface. The retention of the Cry1Ac protein increased by 11.45%, and sprayed nano-Mg(OH)2 was rapidly absorbed by different tissues of tea plants. Moreover, nano-Mg(OH)2 and composites did not significantly affect non-target organisms. These results show that nano-Mg(OH)2 can serve as a safe and effective biopesticide carrier, which provides a new approach for stable and efficient Bt preparation.
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Affiliation(s)
- Xiaohong Pan
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection & Key Laboratory of Biopesticide and Chemical Biology, Ministry of Education & Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, People's Republic of China
| | - Fang Cao
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection & Key Laboratory of Biopesticide and Chemical Biology, Ministry of Education & Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, People's Republic of China
| | - Xueping Guo
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection & Key Laboratory of Biopesticide and Chemical Biology, Ministry of Education & Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, People's Republic of China
| | - Yilin Wang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection & Key Laboratory of Biopesticide and Chemical Biology, Ministry of Education & Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, People's Republic of China
| | - Ziqi Cui
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection & Key Laboratory of Biopesticide and Chemical Biology, Ministry of Education & Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, People's Republic of China
| | - Tianpei Huang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection & Key Laboratory of Biopesticide and Chemical Biology, Ministry of Education & Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, People's Republic of China
| | - Youming Hou
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection & Key Laboratory of Biopesticide and Chemical Biology, Ministry of Education & Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, People's Republic of China
| | - Xiong Guan
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Plant Protection & Key Laboratory of Biopesticide and Chemical Biology, Ministry of Education & Fujian-Taiwan Joint Center for Ecological Control of Crop Pests, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, People's Republic of China
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20
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Wang Y, Yao Y, Zhang Y, Qian X, Guo D, Coates BS. A chromosome-level genome assembly of the soybean pod borer: insights into larval transcriptional response to transgenic soybean expressing the pesticidal Cry1Ac protein. BMC Genomics 2024; 25:355. [PMID: 38594617 PMCID: PMC11005160 DOI: 10.1186/s12864-024-10216-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 03/12/2024] [Indexed: 04/11/2024] Open
Abstract
BACKGROUND Genetically modified (GM) crop plants with transgenic expression of Bacillus thuringiensis (Bt) pesticidal proteins are used to manage feeding damage by pest insects. The durability of this technology is threatened by the selection for resistance in pest populations. The molecular mechanism(s) involved in insect physiological response or evolution of resistance to Bt is not fully understood. RESULTS To investigate the response of a susceptible target insect to Bt, the soybean pod borer, Leguminivora glycinivorella (Lepidoptera: Tortricidae), was exposed to soybean, Glycine max, expressing Cry1Ac pesticidal protein or the non-transgenic parental cultivar. Assessment of larval changes in gene expression was facilitated by a third-generation sequenced and scaffolded chromosome-level assembly of the L. glycinivorella genome (657.4 Mb; 27 autosomes + Z chromosome), and subsequent structural annotation of 18,197 RefSeq gene models encoding 23,735 putative mRNA transcripts. Exposure of L. glycinivorella larvae to transgenic Cry1Ac G. max resulted in prediction of significant differential gene expression for 204 gene models (64 up- and 140 down-regulated) and differential splicing among isoforms for 10 genes compared to unexposed cohorts. Differentially expressed genes (DEGs) included putative peritrophic membrane constituents, orthologs of Bt receptor-encoding genes previously linked or associated with Bt resistance, and those involved in stress responses. Putative functional Gene Ontology (GO) annotations assigned to DEGs were significantly enriched for 36 categories at GO level 2, respectively. Most significantly enriched cellular component (CC), biological process (BP), and molecular function (MF) categories corresponded to vacuolar and microbody, transport and metabolic processes, and binding and reductase activities. The DEGs in enriched GO categories were biased for those that were down-regulated (≥ 0.783), with only MF categories GTPase and iron binding activities were bias for up-regulation genes. CONCLUSIONS This study provides insights into pathways and processes involved larval response to Bt intoxication, which may inform future unbiased investigations into mechanisms of resistance that show no evidence of alteration in midgut receptors.
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Affiliation(s)
- Yangzhou Wang
- Jilin Academy of Agricultural Sciences, Changchun, 130033, China
| | - Yao Yao
- Jilin Academy of Agricultural Sciences, Changchun, 130033, China
| | - Yunyue Zhang
- Jilin Academy of Agricultural Sciences, Changchun, 130033, China
| | - Xueyan Qian
- Jilin Academy of Agricultural Sciences, Changchun, 130033, China
| | - Dongquan Guo
- Jilin Academy of Agricultural Sciences, Changchun, 130033, China.
| | - Brad S Coates
- United States Department of Agriculture, Agricultural Research Service, Corn Insects & Crop Genetics Research Unit, 532 Science II, 2310 Pammel Dr., Ames, IA, 50011, USA.
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21
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Pezzini D, Taylor KL, Reisig DD, Fritz ML. Cross-pollination in seed-blended refuge and selection for Vip3A resistance in a lepidopteran pest as detected by genomic monitoring. Proc Natl Acad Sci U S A 2024; 121:e2319838121. [PMID: 38513093 PMCID: PMC10990109 DOI: 10.1073/pnas.2319838121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Accepted: 12/13/2023] [Indexed: 03/23/2024] Open
Abstract
The evolution of pest resistance to management tools reduces productivity and results in economic losses in agricultural systems. To slow its emergence and spread, monitoring and prevention practices are implemented in resistance management programs. Recent work suggests that genomic approaches can identify signs of emerging resistance to aid in resistance management. Here, we empirically examined the sensitivity of genomic monitoring for resistance management in transgenic Bt crops, a globally important agricultural innovation. Whole genome resequencing of wild North American Helicoverpa zea collected from non-expressing refuge and plants expressing Cry1Ab confirmed that resistance-associated signatures of selection were detectable after a single generation of exposure. Upon demonstrating its sensitivity, we applied genomic monitoring to wild H. zea that survived Vip3A exposure resulting from cross-pollination of refuge plants in seed-blended plots. Refuge seed interplanted with transgenic seed exposed H. zea to sublethal doses of Vip3A protein in corn ears and was associated with allele frequency divergence across the genome. Some of the greatest allele frequency divergence occurred in genomic regions adjacent to a previously described candidate gene for Vip3A resistance. Our work highlights the power of genomic monitoring to sensitively detect heritable changes associated with field exposure to Bt toxins and suggests that seed-blended refuge will likely hasten the evolution of resistance to Vip3A in lepidopteran pests.
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Affiliation(s)
- Daniela Pezzini
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC27513
| | - Katherine L. Taylor
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC27513
- Department of Entomology, University of Maryland, College Park, MD20742
| | - Dominic D. Reisig
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC27513
| | - Megan L. Fritz
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC27513
- Department of Entomology, University of Maryland, College Park, MD20742
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22
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Miranda MP, Fitches EC, Sukiran NA, Eduardo WI, Garcia RB, Jaciani FJ, Readshaw JJ, Bell J, Peña L. Spider venom neurotoxin based bioinsecticides: A novel bioactive for the control of the Asian citrus psyllid Diaphorina citri (Hemiptera). Toxicon 2024; 239:107616. [PMID: 38218384 DOI: 10.1016/j.toxicon.2024.107616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 01/10/2024] [Accepted: 01/10/2024] [Indexed: 01/15/2024]
Abstract
The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is a key vector of the phloem-limited bacteria Candidatus Liberibacter asiaticus (CLas) associated with huanglongbing (HLB), the most serious and currently incurable disease of citrus worldwide. Here we report the first investigation into the potential use of a spider venom-derived recombinant neurotoxin, ω/κ-HxTx-Hv1h (hereafter HxTx-Hv1h) when delivered alone or when fused to snowdrop lectin (Galanthus nivalis agglutinin; GNA) to control D. citri. Proteins, including GNA alone, were purified from fermented transformed yeast Pichia pastoris cultures. Recombinant HxTx-Hv1h, HxTx-Hv1h/GNA and GNA were all orally toxic to D. citri, with Day 5 median lethal concentrations (LC50) derived from dose-response artificial diet assays of 27, 20 and 52 μM, respectively. Western analysis of whole insect protein extracts confirmed that psyllid mortality was attributable to protein ingestion and that the fusion protein was stable to cleavage by D. citri proteases. When applied topically (either via droplet or spray) HxTx-Hv1h/GNA was the most effective of the proteins causing >70 % mortality 5 days post treatment, some 2 to 3-fold higher levels of mortality as compared to the toxin alone. By contrast, no significant mortality or phenotypic effects were observed for bumble bees (Bombus terrestris L.) fed on the recombinant proteins in acute toxicity assays. This suggests that HxTx-Hv1h/GNA has potential as a novel bioinsecticide for the management of D. citri offering both enhanced target specificity as compared to chemical pesticides and compatibility with integrated pest management (IPM) strategies.
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Affiliation(s)
- Marcelo P Miranda
- Fund for Citrus Protection (Fundecitrus), Research and Development, Avenida Dr. Adhemar Pereira de Barros, 201, 14807- 040, Araraquara, SP, Brazil
| | - Elaine C Fitches
- School of Biosciences, University of Durham, Durham, DH1 3LE, United Kingdom.
| | - Nur Afiqah Sukiran
- School of Biosciences, University of Durham, Durham, DH1 3LE, United Kingdom
| | - Wellington I Eduardo
- Fund for Citrus Protection (Fundecitrus), Research and Development, Avenida Dr. Adhemar Pereira de Barros, 201, 14807- 040, Araraquara, SP, Brazil
| | - Rafael B Garcia
- Fund for Citrus Protection (Fundecitrus), Research and Development, Avenida Dr. Adhemar Pereira de Barros, 201, 14807- 040, Araraquara, SP, Brazil
| | - Fabrício J Jaciani
- Fund for Citrus Protection (Fundecitrus), Research and Development, Avenida Dr. Adhemar Pereira de Barros, 201, 14807- 040, Araraquara, SP, Brazil
| | - Jennifer J Readshaw
- School of Biosciences, University of Durham, Durham, DH1 3LE, United Kingdom
| | - Jack Bell
- School of Biosciences, University of Durham, Durham, DH1 3LE, United Kingdom
| | - Leandro Peña
- Instituto de Biologıa Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas (IBMCP-CSIC), Universidad Politécnica de Valencia, Spain
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23
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Calvin W, Yang F, Kennedy H, Marçon PG, Kerns DL. Susceptibility of Field and Laboratory Bt-Susceptible and Resistant Strains of Helicoverpa zea (Boddie) to HearNPV. PLANTS (BASEL, SWITZERLAND) 2024; 13:529. [PMID: 38498539 PMCID: PMC10892202 DOI: 10.3390/plants13040529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 01/21/2024] [Accepted: 02/05/2024] [Indexed: 03/20/2024]
Abstract
During 2021 and 2022, eight field-collected and five laboratory Helicoverpa zea strains with varying susceptibility to different Bt proteins were evaluated for their responses against HearNPV using diet-overlay bioassays. The five laboratory strains included SS (susceptible to all Bt proteins), CRY-RR (resistant to Cry1 and Cry2), VIP-RR-70 (resistant to Vip3Aa), VIP-RR-15 (resistant to Vip3Aa), and TRE-RR (resistant to Cry1, Cry2, and Vip3Aa). Our findings showed that the susceptibility of TRE-RR, VIP-RR-70, and VIP-RR-15 strains to HearNPV was similar to that of the SS strain. However, the field and Cry-RR strains were more resistant to HearNPV compared to the SS strain. Because most feral H. zea strains in the southern U.S. have developed practical resistance to Cry Bt proteins but remain susceptible to Vip3Aa, the results suggest that the reduced susceptibility to HearNPV in H. zea may be associated with the resistance to Cry Bt proteins but not with the resistance to Vip3Aa. Correlation analysis confirmed that there was a significant positive relationship between Cry resistance and HearNPV resistance, but not between the Vip3Aa resistance and HearNPV resistance in H. zea. Our findings provide valuable insights into the relationship between susceptibility to HearNPV and resistance to Bt proteins in H. zea.
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Affiliation(s)
- Wilfrid Calvin
- Department of Entomology, Texas A&M University, 2475 TAMU, College Station, TX 77843, USA
- Department of Entomology, University of Minnesota, Saint Paul, MN 55108, USA
| | - Fei Yang
- Department of Entomology, University of Minnesota, Saint Paul, MN 55108, USA
| | - Haley Kennedy
- Department of Entomology, Texas A&M University, 2475 TAMU, College Station, TX 77843, USA
| | | | - David L Kerns
- Department of Entomology, Texas A&M University, 2475 TAMU, College Station, TX 77843, USA
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24
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Alves GB, Lemes TSO, Pereira EJG, Jurat-Fuentes JL, Smagghe G, Santos GR, Haddi K, Corrêa RFT, Melo FL, Jumbo LOV, Oliveira EE, Peron AJ, Ribeiro BM, Aguiar RWS. Draft genome of neotropical Bacillus thuringiensis UFT038 and its potential against lepidopteran soybean pests. Folia Microbiol (Praha) 2024; 69:91-99. [PMID: 38017300 DOI: 10.1007/s12223-023-01114-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 11/15/2023] [Indexed: 11/30/2023]
Abstract
Bacillus thuringiensis (Bt) is known for its Cry and Vip3A pesticidal proteins with high selectivity to target pests. Here, we assessed the potential of a novel neotropical Bt strain (UFT038) against six lepidopteran pests, including two Cry-resistant populations of fall armyworm, Spodoptera frugiperda. We also sequenced and analyzed the genome of Bt UFT038 to identify genes involved in insecticidal activities or encoding other virulence factors. In toxicological bioassays, Bt UFT038 killed and inhibited the neonate growth in a concentration-dependent manner. Bt UFT038 and HD-1 were equally toxic against S. cosmioides, S. frugiperda (S_Bt and R_Cry1 + 2Ab populations), Helicoverpa zea, and H. armigera. However, larval growth inhibition results indicated that Bt UFT038 was more toxic than HD-1 to S. cosmioides, while HD-1 was more active against Chrysodeixis includens. The draft genome of Bt UFT038 showed the cry1Aa8, cry1Ac11, cry1Ia44, cry2Aa9, cry2Ab35, and vip3Af5 genes. Besides this, genes encoding the virulence factors (inhA, plcA, piplC, sph, and chi1-2) and toxins (alo, cytK, hlyIII, hblA-D, and nheA-C) were also identified. Collectively, our findings reveal the potential of the Bt UFT038 strain as a source of insecticidal genes against lepidopteran pests, including S. cosmioides and S. frugiperda.
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Affiliation(s)
- Giselly B Alves
- Departamento de Biotecnologia, Universidade Federal de Tocantins, Gurupi, TO, 77413-070, Brazil
| | - Timóteo S O Lemes
- Departamento de Biotecnologia, Universidade Federal de Tocantins, Gurupi, TO, 77413-070, Brazil
| | - Eliseu J G Pereira
- Departamento de Entomologia, Universidade Federal de Viçosa, Viçosa, MG, 36570-900, Brazil
| | - Juan L Jurat-Fuentes
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, TN, 37996, USA
| | - Guy Smagghe
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, B-9000, Ghent, Belgium
| | - Gil R Santos
- Departamento de Biotecnologia, Universidade Federal de Tocantins, Gurupi, TO, 77413-070, Brazil
| | - Khalid Haddi
- Departamento de Entomologia, Universidade Federal de Lavras, Lavras, MG, 37200-900, Brazil
| | - Roberto F T Corrêa
- Departamento de Biologia Celular, Universidade de Brasília, Brasília, DF, 70910-900, Brazil
| | - Fernando L Melo
- Departamento de Biologia Celular, Universidade de Brasília, Brasília, DF, 70910-900, Brazil
| | - Luis O Viteri Jumbo
- Departamento de Biotecnologia, Universidade Federal de Tocantins, Gurupi, TO, 77413-070, Brazil
- Carrera de Agronomía, Universidad Nacional de Loja (UNL), Loja, 110103, Ecuador
| | - Eugenio E Oliveira
- Departamento de Entomologia, Universidade Federal de Viçosa, Viçosa, MG, 36570-900, Brazil
| | - Antônio J Peron
- Departamento de Biotecnologia, Universidade Federal de Tocantins, Gurupi, TO, 77413-070, Brazil
| | - Bergmann M Ribeiro
- Departamento de Biologia Celular, Universidade de Brasília, Brasília, DF, 70910-900, Brazil
| | - Raimundo W S Aguiar
- Departamento de Biotecnologia, Universidade Federal de Tocantins, Gurupi, TO, 77413-070, Brazil.
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25
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Chen G, Li Q, Zhang C, Zhao W, Jurat-Fuentes JL, Zhou X, Chen F, Yang X, Han L. Synergism of Cry1Ca toxicity by gut resident Enterococcus spp. in the rice stem borer, Chilo suppressalis. Int J Biol Macromol 2024; 257:128654. [PMID: 38065453 DOI: 10.1016/j.ijbiomac.2023.128654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 11/29/2023] [Accepted: 12/05/2023] [Indexed: 01/26/2024]
Abstract
The bacterium Bacillus thuringiensis (Bt) is the most economically successful biopesticide to date, and Bt insecticidal proteins are produced in transgenic crops for pest control. However, relevant details in the Bt-mediated killing process remain undefined. In our previous research, we observed reduced larval susceptibility to Bt Cry1Ca in Chilo suppressalis, a major rice pest in China, after gut microbiota elimination. Here, we tested the hypothesis that gut microbiota, particularly abundant Enterococcus spp., influences C. suppressalis susceptibility to Cry1Ca. We isolated and identified four Enterococcus spp. from C. suppressalis gut microbiota and evaluated their impact on Cry1Ca toxicity. Among the four Enterococcus spp. identified, three of them (E. casseliflavus, E. faecalis, and E. mundtii) dramatically increased larval mortality when introduced in axenic C. suppressalis challenged with Cry1Ca. Gut epithelial damage by Cry1Ca promoted the translocation of Enterococcus spp. from the gut lumen into the hemocoel, where they proliferated and induced larval melanization and hemocyte apoptosis. Our combined findings demonstrate that the presence of specific gut microbiota can greatly affect susceptibility to Cry1Ca through melanization and apoptosis of hemocytes. Better understanding of the Bt intoxication process guides the development of bio-enhancers for Bt-based microbial biopesticides and potential improvement of transgenic crops.
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Affiliation(s)
- Geng Chen
- The State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Qianwen Li
- The State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Chen Zhang
- The State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Wanxuan Zhao
- The State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | | | - Xuguo Zhou
- Department of Entomology, University of Kentucky, Lexington 40546, USA
| | - Fajun Chen
- Department of Entomology, College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Xiaowei Yang
- The State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
| | - Lanzhi Han
- The State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
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26
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Guo Z, Bai Y, Zhang X, Guo L, Zhu L, Sun D, Sun K, Xu X, Yang X, Xie W, Wang S, Wu Q, Crickmore N, Zhou X, Zhang Y. RNA m 6 A Methylation Suppresses Insect Juvenile Hormone Degradation to Minimize Fitness Costs in Response to A Pathogenic Attack. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2307650. [PMID: 38087901 PMCID: PMC10853702 DOI: 10.1002/advs.202307650] [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: 10/12/2023] [Revised: 12/05/2023] [Indexed: 02/10/2024]
Abstract
Bioinsecticides and transgenic crops based on the bacterial pathogen Bacillus thuringiensis (Bt) can effectively control diverse agricultural insect pests, nevertheless, the evolution of resistance without obvious fitness costs has seriously eroded the sustainable use of these Bt products. Recently, it has been discovered that an increased titer of juvenile hormone (JH) favors an insect host (Plutella xylostella) to enhance fitness whilst resisting the Bt pathogen, however, the underlying regulatory mechanisms of the increased JH titer are obscure. Here, the involvement of N6 -methyladenosine (m6 A) RNA modification in modulating the availability of JH in this process is defined. Specifically, it is found that two m6 A methyltransferase subunit genes, PxMettl3 and PxMettl14, repress the expression of a key JH-degrading enzyme JH esterase (JHE) to induce an increased JH titer, mitigating the fitness costs associated with a robust defense against the Bt pathogen. This study identifies an as-yet uncharacterized m6 A-mediated epigenetic regulator of insect hormones for maintaining fitness during pathogen defense and unveils an emerging Bt resistance-related m6 A methylation atlas in insects, which further expands the functional landscape of m6 A modification and showcases the pivotal role of epigenetic regulation in host-pathogen interactions.
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Affiliation(s)
- Zhaojiang Guo
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Yang Bai
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Xinyi Zhang
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Le Guo
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Liuhong Zhu
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Dan Sun
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Kaiyue Sun
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Xudan Xu
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Xin Yang
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Wen Xie
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Shaoli Wang
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Qingjun Wu
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
| | - Neil Crickmore
- School of Life SciencesUniversity of SussexBrightonBN1 9QGUK
| | - Xuguo Zhou
- Department of EntomologyUniversity of KentuckyLexingtonKentucky40546‐0091USA
| | - Youjun Zhang
- State Key Laboratory of Vegetable BiobreedingDepartment of Plant ProtectionInstitute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing100081China
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27
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He X, Yang Y, Soberón M, Bravo A, Zhang L, Zhang J, Wang Z. Bacillus thuringiensis Cry9Aa Insecticidal Protein Domain I Helices α3 and α4 Are Two Core Regions Involved in Oligomerization and Toxicity. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:1321-1329. [PMID: 38175929 DOI: 10.1021/acs.jafc.3c08070] [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: 01/06/2024]
Abstract
Bacillus thuringiensis Cry9 proteins show high insecticidal activity against different lepidopteran pests. Cry9 could be a valuable alternative to Cry1 proteins because it showed a synergistic effect with no cross-resistance. However, the pore-formation region of the Cry9 proteins is still unclear. In this study, nine mutations of certain Cry9Aa helices α3 and α4 residues resulted in a complete loss of insecticidal activity against the rice pest Chilo suppressalis; however, the protein stability and receptor binding ability of these mutants were not affected. Among these mutants, Cry9Aa-D121R, Cry9Aa-D125R, Cry9Aa-D163R, Cry9Aa-E165R, and Cry9Aa-D167R are unable to form oligomers in vitro, while the oligomers formed by Cry9Aa-R156D, Cry9Aa-R158D, and Cry9Aa-R160D are unstable and failed to insert into the membrane. These data confirmed that helices α3 and α4 of Cry9Aa are involved in oligomerization, membrane insertion, and toxicity. The knowledge of Cry9 pore-forming action may promote its application as an alternative to Cry1 insecticidal proteins.
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Affiliation(s)
- Xiang He
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, Anhui Province 230036, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Yanchao Yang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Mario Soberón
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Apdo. Postal 510-3, Morelos 62250, Mexico
| | - Alejandra Bravo
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Apdo. Postal 510-3, Morelos 62250, Mexico
| | - Lihong Zhang
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, Anhui Province 230036, China
| | - Jie Zhang
- Anhui Province Engineering Laboratory for Green Pesticide Development and Application, School of Plant Protection, Anhui Agricultural University, Hefei, Anhui Province 230036, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
| | - Zeyu Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China
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Li S, Xu F, Zhang Y, Gao Z, Han Z, Feng C. Identification and characteristic analysis of an extracellular signal-regulated kinase from Ostrinia furnacalis Guenée. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2024; 115:e22077. [PMID: 38288489 DOI: 10.1002/arch.22077] [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: 10/05/2023] [Revised: 11/18/2023] [Accepted: 12/13/2023] [Indexed: 02/01/2024]
Abstract
The extracellular signal-regulated kinase (ERK) pathway, a critical genetic determinant, controls diverse physiological functions, including innate immunity, development, and stress response. In the current study, a full-length cDNA (1592bp) encoding the ERK gene (OfERK) was cloned from Ostrinia furnacalis Guenée (GenBank accession number: MF797866). The open reading frame of the OfERK gene encoded 364 amino acids and shared 96.43%-98.08% amino acid identities with other insect mitogen-activated protein kinases. For spatiotemporal analysis of the expression pattern, OfERK exhibited a significant peak expression on the 3rd day of the pupa stage and showed the highest expression in hemocytes specifically. Indirect immunofluorescence assays and immuno-electron microscopy revealed a wide distribution of the OfERK protein in hemocytes and epidermis. Moreover, the results demonstrated that the Bt Cry1Ab-activated toxin significantly induces the expression of OfERK. Other genes related to immune response, development, and stress response exhibited dynamic changes in expression after Cry1Ab oral treatment. The expression of OfERK was downregulated through RNA interference, and the correlation of its expression with other related genes was verified using quantitative real-time polymerase chain reaction. Our study provides valuable insights into the regulatory mechanism of ERK in insects for future studies.
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Affiliation(s)
- Shuzhong Li
- Department of Entomology, College of Plant Protection, Yangzhou University, Yangzhou, Jiangsu, China
| | - Fuqiang Xu
- Department of Entomology, College of Plant Protection, Yangzhou University, Yangzhou, Jiangsu, China
| | - Yiqiang Zhang
- Department of Entomology, College of Plant Protection, Yangzhou University, Yangzhou, Jiangsu, China
| | - Zupeng Gao
- Department of Entomology, College of Plant Protection, Yangzhou University, Yangzhou, Jiangsu, China
| | - Zhaoyang Han
- Department of Entomology, College of Plant Protection, Yangzhou University, Yangzhou, Jiangsu, China
| | - Congjing Feng
- Department of Entomology, College of Plant Protection, Yangzhou University, Yangzhou, Jiangsu, China
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Rezende TMT, Menezes HSG, Rezende AM, Cavalcanti MP, Silva YMG, de-Melo-Neto OP, Romão TP, Silva-Filha MHNL. Culex quinquefasciatus Resistant to the Binary Toxin from Lysinibacillus sphaericus Displays a Consistent Downregulation of Pantetheinase Transcripts. Biomolecules 2023; 14:33. [PMID: 38254633 PMCID: PMC10813629 DOI: 10.3390/biom14010033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 12/07/2023] [Accepted: 12/11/2023] [Indexed: 01/24/2024] Open
Abstract
Culex quinquefasciatus resistance to the binary (Bin) toxin, the major larvicidal component from Lysinibacillus sphaericus, is associated with mutations in the cqm1 gene, encoding the Bin-toxin receptor. Downregulation of the cqm1 transcript was found in the transcriptome of larvae resistant to the L. sphaericus IAB59 strain, which produces both the Bin toxin and a second binary toxin, Cry48Aa/Cry49Aa. Here, we investigated the transcription profiles of two other mosquito colonies having Bin resistance only. These confirmed the cqm1 downregulation and identified transcripts encoding the enzyme pantetheinase as the most downregulated mRNAs in both resistant colonies. Further quantification of these transcripts reinforced their strong downregulation in Bin-resistant larvae. Multiple genes were found encoding this enzyme in Cx. quinquefasciatus and a recombinant pantetheinase was then expressed in Escherichia coli and Sf9 cells, with its presence assessed in the midgut brush border membrane of susceptible larvae. The pantetheinase was expressed as a ~70 kDa protein, potentially membrane-bound, which does not seem to be significantly targeted by glycosylation. This is the first pantetheinase characterization in mosquitoes, and its remarkable downregulation might reflect features impacted by co-selection with the Bin-resistant phenotype or potential roles in the Bin-toxin mode of action that deserve to be investigated.
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Affiliation(s)
- Tatiana M. T. Rezende
- Department of Entomology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (T.M.T.R.); (H.S.G.M.); (Y.M.G.S.); (T.P.R.)
| | - Heverly S. G. Menezes
- Department of Entomology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (T.M.T.R.); (H.S.G.M.); (Y.M.G.S.); (T.P.R.)
| | - Antonio M. Rezende
- Department of Microbiology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (A.M.R.); (M.P.C.); (O.P.d.-M.-N.)
| | - Milena P. Cavalcanti
- Department of Microbiology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (A.M.R.); (M.P.C.); (O.P.d.-M.-N.)
| | - Yuri M. G. Silva
- Department of Entomology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (T.M.T.R.); (H.S.G.M.); (Y.M.G.S.); (T.P.R.)
| | - Osvaldo P. de-Melo-Neto
- Department of Microbiology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (A.M.R.); (M.P.C.); (O.P.d.-M.-N.)
| | - Tatiany P. Romão
- Department of Entomology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (T.M.T.R.); (H.S.G.M.); (Y.M.G.S.); (T.P.R.)
| | - Maria Helena N. L. Silva-Filha
- Department of Entomology, Instituto Aggeu Magalhães-Fiocruz, Recife 50740-465, PE, Brazil; (T.M.T.R.); (H.S.G.M.); (Y.M.G.S.); (T.P.R.)
- National Institute for Molecular Entomology, Rio de Janeiro 21941-902, RJ, Brazil
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Kerns DD, Yang F, Kerns DL, Stewart SD, Jurat-Fuentes JL. Reduced toxin binding associated with resistance to Vip3Aa in the corn earworm ( Helicoverpa zea). Appl Environ Microbiol 2023; 89:e0164423. [PMID: 38014960 PMCID: PMC10734485 DOI: 10.1128/aem.01644-23] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 10/17/2023] [Indexed: 11/29/2023] Open
Abstract
IMPORTANCE Helicoverpa zea is a major crop pest in the United States that is managed with transgenic corn and cotton that produce insecticidal proteins from the bacterium, Bacillus thuringiensis (Bt). However, H. zea has evolved widespread resistance to the Cry proteins produced in Bt corn and cotton, leaving Vip3Aa as the only plant-incorporated protectant in Bt crops that consistently provides excellent control of H. zea. The benefits provided by Bt crops will be substantially reduced if widespread Vip3Aa resistance develops in H. zea field populations. Therefore, it is important to identify resistance alleles and mechanisms that contribute to Vip3Aa resistance to ensure that informed resistance management strategies are implemented. This study is the first report of reduced binding of Vip3Aa to midgut receptors associated with resistance.
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Affiliation(s)
- Dawson D. Kerns
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, USA
| | - Fei Yang
- Department of Entomology, University of Minnesota, St. Paul, Minnesota, USA
| | - David L. Kerns
- Department of Entomology, Texas A&M University, College Station, Texas, USA
| | - Scott D. Stewart
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, USA
| | - Juan Luis Jurat-Fuentes
- Department of Entomology and Plant Pathology, University of Tennessee, Knoxville, Tennessee, USA
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Sauka DH, Peralta C, Pérez MP, Molla A, Fernandez-Göbel T, Ocampo F, Palma L. Bacillus thuringiensis Bt_UNVM-84, a Novel Strain Showing Insecticidal Activity against Anthonomus grandis Boheman (Coleoptera: Curculionidae). Toxins (Basel) 2023; 16:4. [PMID: 38276528 PMCID: PMC10819922 DOI: 10.3390/toxins16010004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 12/16/2023] [Accepted: 12/18/2023] [Indexed: 01/27/2024] Open
Abstract
Bacillus thuringiensis is a Gram-positive bacterium known for its insecticidal proteins effective against various insect pests. However, limited strains and proteins target coleopteran pests like Anthonomous grandis Boheman, causing substantial economic losses in the cotton industry. This study focuses on characterizing a Bacillus sp. strain, isolated from Oncativo (Argentina), which exhibits ovoid to amorphous parasporal crystals and was designated Bt_UNVM-84. Its genome encodes genes for the production of two pairs of binary Vpb1/Vpa2 proteins and three Cry-like proteins showing similarity with different Cry8 proteins. Interestingly, this gene content was found to be conserved in a previously characterized Argentine isolate of B. thuringiensis designated INTA Fr7-4. SDS-PAGE analysis revealed a major band of 130 kDa that is proteolytically processed to an approximately 66-kDa protein fragment by trypsin. Bioassays performed with spore-crystal mixtures demonstrated an interesting insecticidal activity against the cotton boll weevil A. grandis neonate larvae, resulting in 91% mortality. Strain Bt_UNVM-84 is, therefore, an interesting candidate for the efficient biological control of this species, causing significant economic losses in the cotton industry in the Americas.
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Affiliation(s)
- Diego Herman Sauka
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires C1425FQB, Argentina; (D.H.S.); (C.P.)
- Instituto Nacional de Tecnología Agropecuaria (INTA), Instituto de Microbiología y Zoología Agrícola (IMYZA), Hurlingham, Ciudad Autónoma de Buenos Aires 1686, Argentina;
| | - Cecilia Peralta
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires C1425FQB, Argentina; (D.H.S.); (C.P.)
- Instituto Multidisciplinario de Investigación y Transferencia Agroalimentaria y Biotecnológica (IMITAB), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Villa María (UNVM), Villa María 1555, Argentina;
- Laboratorio de Control Biotecnológico de Plagas, Instituto BIOTECMED, Departamento de Genética, Universitat de València, 46100 València, Spain
| | - Melisa Paula Pérez
- Instituto Nacional de Tecnología Agropecuaria (INTA), Instituto de Microbiología y Zoología Agrícola (IMYZA), Hurlingham, Ciudad Autónoma de Buenos Aires 1686, Argentina;
| | - Antonella Molla
- Instituto Multidisciplinario de Investigación y Transferencia Agroalimentaria y Biotecnológica (IMITAB), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Villa María (UNVM), Villa María 1555, Argentina;
| | - Tadeo Fernandez-Göbel
- Elytron Biotech S.A., 275 Ing. Enrique Butty Street, Ciudad Autónoma de Buenos Aires C1001, Argentina; (T.F.-G.); (F.O.)
| | - Federico Ocampo
- Elytron Biotech S.A., 275 Ing. Enrique Butty Street, Ciudad Autónoma de Buenos Aires C1001, Argentina; (T.F.-G.); (F.O.)
| | - Leopoldo Palma
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Ciudad Autónoma de Buenos Aires C1425FQB, Argentina; (D.H.S.); (C.P.)
- Instituto Multidisciplinario de Investigación y Transferencia Agroalimentaria y Biotecnológica (IMITAB), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Villa María (UNVM), Villa María 1555, Argentina;
- Laboratorio de Control Biotecnológico de Plagas, Instituto BIOTECMED, Departamento de Genética, Universitat de València, 46100 València, Spain
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Gan C, Zhang Z, Jin Z, Wang F, Fabrick JA, Wu Y. Helicoverpa armigera ATP-binding cassette transporter ABCA2 is a functional receptor of Bacillus thuringiensis Cry2Ab toxin. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2023; 197:105658. [PMID: 38072533 DOI: 10.1016/j.pestbp.2023.105658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 10/17/2023] [Accepted: 10/19/2023] [Indexed: 12/18/2023]
Abstract
Crystalline (Cry) proteins from the bacterium Bacillus thuringiensis (Bt) are widely used in transgenic crops to control important insect pests. Bt crops have many benefits compared with traditional broad-spectrum insecticides, including improved pest control with reduced negative impacts on off-target organisms and fewer environmental consequences. Transgenic corn and cotton producing Cry2Ab Bt toxin are used globally to control several major lepidopteran pests, including the cotton bollworm, Helicoverpa armigera. Resistance to the Cry2Ab toxin and to Bt crops producing Cry2Ab is associated with mutations in the midgut ATP-binding cassette transporter ABCA2 gene in several lepidopterans. Gene-editing knockout has further shown that ABCA2 plays an important functional role in Cry2Ab intoxication. However, the precise role of ABCA2 in the mode of action of Cry2Ab has yet to be reported. Here, we used two in vitro expression systems to study the roles of the H. armigera ABCA2 (HaABCA2) protein in Cry2Ab intoxication. Cry2Ab bound to cultured Sf9 insect cells producing HaABCA2, resulting in specific and dose-dependent susceptibility to Cry2Ab. In contrast, Sf9 cells expressing recombinant mutant proteins missing at least one of the extracellular loop regions 1, 3, 4, and 6 or the intracellular loop containing nucleotide-binding domain 1 lost susceptibility to Cry2Ab, indicating these regions are important for receptor function. Consistent with these results, Xenopus laevis oocytes expressing recombinant HaABCA2 showed strong ion membrane flux in the presence of Cry2Ab, suggesting that HaABCA2 is involved in promoting pore formation during Cry2Ab intoxication. Together with previously published data, our results support HaABCA2 being an important receptor of Cry2Ab where it functions to promote intoxication in H. armigera.
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Affiliation(s)
- Chunxia Gan
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Zheng Zhang
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Zeng Jin
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Falong Wang
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China
| | - Jeffrey A Fabrick
- USDA ARS, U.S. Arid Land Agricultural Research Center, Maricopa, AZ, USA
| | - Yidong Wu
- College of Plant Protection, Nanjing Agricultural University, Nanjing, China.
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Courtier-Orgogozo V. The loci of insect phenotypic evolution. CURRENT OPINION IN INSECT SCIENCE 2023; 60:101134. [PMID: 37858791 DOI: 10.1016/j.cois.2023.101134] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 10/10/2023] [Accepted: 10/13/2023] [Indexed: 10/21/2023]
Abstract
Insects are important elements of terrestrial ecosystems because they pollinate plants, destroy crops, transmit diseases to livestock and humans, and are important components of food chains. Here, I used Gephebase, a manually curated database of genetic variants associated with natural and domesticated trait variation, to explore current knowledge about the genes and the mutations known to contribute to natural phenotypic variation in insects. Analysis of over 600 mutations reveals that data are concentrated toward certain species and traits and that experimental approaches have changed over time. The distribution of coding and cis-regulatory changes varies with traits, experimental approaches, and identified gene loci. Recent studies highlight the important role of standing variation, repeated mutations in hotspot genes, recombination, inversions, and introgression.
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Chen Z, Shi Y, Wang D, Liu X, Jiao X, Gao X, Jiang K. Structural insight into Bacillus thuringiensis Sip1Ab reveals its similarity to ETX_MTX2 family beta-pore-forming toxin. PEST MANAGEMENT SCIENCE 2023; 79:4264-4273. [PMID: 37341620 DOI: 10.1002/ps.7622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 06/15/2023] [Accepted: 06/21/2023] [Indexed: 06/22/2023]
Abstract
BACKGROUND Microbially derived, protein-based biopesticides are an important approach for sustainable pest management. The secreted insecticidal proteins (Sips) produced by the bacterium Bacillus thuringiensis exhibit potent insecticidal activity against coleopteran pests and are, therefore, attractive as candidate biopesticides. However, the modes-of-action of Sips are unclear as comprehensive structural information for these proteins is lacking. RESULTS Using X-ray crystallography, we elucidated the structure of monomeric Sip1Ab at 2.28 Å resolution. Structural analyses revealed that Sip1Ab has the three domains and conserved fold characteristic of other aerolysin-like beta-pore-forming toxins (β-PFTs). Based on the sequence and structural similarities between Sip1Ab and other ETX_MTX2 subfamily toxins, we suggested the mechanism of these proteins and proposed that it is common to them all. CONCLUSION The atomic-level structural data for Sip1Ab generated by the present study could facilitate future structural and mechanistic research on Sips as well as their application in sustainable insect pest management. © 2023 Society of Chemical Industry.
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Affiliation(s)
- Zhe Chen
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Yiting Shi
- Taishan College, Shandong University, Jinan, China
| | - Dongdong Wang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Xiaoyu Liu
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Xuyao Jiao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Xiang Gao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Kun Jiang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
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Wei JZ, Lum A, Schepers E, Liu L, Weston RT, McGinness BS, Heckert MJ, Xie W, Kassa A, Bruck D, Rauscher G, Kapka-Kitzman D, Mathis JP, Zhao JZ, Sethi A, Barry J, Lu AL, Brugliera F, Lee EL, van derWeerden NL, Eswar N, Maher MJ, Anderson MA. Novel insecticidal proteins from ferns resemble insecticidal proteins from Bacillus thuringiensis. Proc Natl Acad Sci U S A 2023; 120:e2306177120. [PMID: 37871210 PMCID: PMC10622923 DOI: 10.1073/pnas.2306177120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Accepted: 08/18/2023] [Indexed: 10/25/2023] Open
Abstract
Lepidopterans affect crop production worldwide. The use of transgenes encoding insecticidal proteins from Bacillus thuringiensis (Bt) in crop plants is a well-established technology that enhances protection against lepidopteran larvae. Concern about widespread field-evolved resistance to Bt proteins has highlighted an urgent need for new insecticidal proteins with different modes or sites of action. We discovered a new family of insecticidal proteins from ferns. The prototype protein from Pteris species (Order Polypodiales) and variants from two other orders of ferns, Schizaeales and Ophioglossales, were effective against important lepidopteran pests of maize and soybean in diet-based assays. Transgenic maize and soybean plants producing these proteins were more resistant to insect damage than controls. We report here the crystal structure of a variant of the prototype protein to 1.98 Å resolution. Remarkably, despite being derived from plants, the structure resembles the 3-domain Cry proteins from Bt but has only two out of three of their characteristic domains, lacking the C-terminal domain which is typically required for their activities. Two of the fern proteins were effective against strains of fall armyworm that were resistant to Bt 3-domain Cry proteins Cry1Fa or Cry2A.127. This therefore represents a novel family of insecticidal proteins that have the potential to provide future tools for pest control.
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Affiliation(s)
| | - Amy Lum
- Corteva Agriscience, Johnston, IA50131
| | | | - Lu Liu
- Corteva Agriscience, Johnston, IA50131
| | - Ross T. Weston
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC3086, Australia
- Hexima Ltd., La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC3086, Australia
| | - Bruce S. McGinness
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC3086, Australia
- Hexima Ltd., La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC3086, Australia
| | | | | | | | | | | | | | | | | | | | | | | | - Filippa Brugliera
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC3086, Australia
- Hexima Ltd., La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC3086, Australia
| | - Eunice L. Lee
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC3086, Australia
- Hexima Ltd., La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC3086, Australia
| | - Nicole L. van derWeerden
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC3086, Australia
- Hexima Ltd., La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC3086, Australia
| | | | - Megan J. Maher
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC3086, Australia
- School of Chemistry and The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC3052, Australia
| | - Marilyn A. Anderson
- Department of Biochemistry and Chemistry, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC3086, Australia
- Hexima Ltd., La Trobe Institute for Molecular Science, La Trobe University, Melbourne, VIC3086, Australia
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Jin M, Shan Y, Peng Y, Wang W, Zhang H, Liu K, Heckel DG, Wu K, Tabashnik BE, Xiao Y. Downregulation of a transcription factor associated with resistance to Bt toxin Vip3Aa in the invasive fall armyworm. Proc Natl Acad Sci U S A 2023; 120:e2306932120. [PMID: 37874855 PMCID: PMC10622909 DOI: 10.1073/pnas.2306932120] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 09/11/2023] [Indexed: 10/26/2023] Open
Abstract
Transgenic crops producing insecticidal proteins from Bacillus thuringiensis (Bt) have revolutionized control of some major pests. However, more than 25 cases of field-evolved practical resistance have reduced the efficacy of transgenic crops producing crystalline (Cry) Bt proteins, spurring adoption of alternatives including crops producing the Bt vegetative insecticidal protein Vip3Aa. Although practical resistance to Vip3Aa has not been reported yet, better understanding of the genetic basis of resistance to Vip3Aa is urgently needed to proactively monitor, delay, and counter pest resistance. This is especially important for fall armyworm (Spodoptera frugiperda), which has evolved practical resistance to Cry proteins and is one of the world's most damaging pests. Here, we report the identification of an association between downregulation of the transcription factor gene SfMyb and resistance to Vip3Aa in S. frugiperda. Results from a genome-wide association study, fine-scale mapping, and RNA-Seq identified this gene as a compelling candidate for contributing to the 206-fold resistance to Vip3Aa in a laboratory-selected strain. Experimental reduction of SfMyb expression in a susceptible strain using RNA interference (RNAi) or CRISPR/Cas9 gene editing decreased susceptibility to Vip3Aa, confirming that reduced expression of this gene can cause resistance to Vip3Aa. Relative to the wild-type promoter for SfMyb, the promoter in the resistant strain has deletions and lower activity. Data from yeast one-hybrid assays, genomics, RNA-Seq, RNAi, and proteomics identified genes that are strong candidates for mediating the effects of SfMyb on Vip3Aa resistance. The results reported here may facilitate progress in understanding and managing pest resistance to Vip3Aa.
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Affiliation(s)
- Minghui Jin
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies (Hainan), Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen518116, China
- The State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing100193, China
| | - Yinxue Shan
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies (Hainan), Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen518116, China
| | - Yan Peng
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies (Hainan), Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen518116, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan430070, China
| | - Wenhui Wang
- The State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing100193, China
| | - Huihui Zhang
- Institute of Entomology, School of Life Sciences, Central China Normal University, Wuhan430079, China
| | - Kaiyu Liu
- Institute of Entomology, School of Life Sciences, Central China Normal University, Wuhan430079, China
| | - David G. Heckel
- Department of Entomology, Max Planck Institute for Chemical Ecology, JenaD-07745, Germany
| | - Kongming Wu
- The State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing100193, China
| | | | - Yutao Xiao
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies (Hainan), Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen518116, China
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Zhang Y, Zhang S, Xu L. The pivotal roles of gut microbiota in insect plant interactions for sustainable pest management. NPJ Biofilms Microbiomes 2023; 9:66. [PMID: 37735530 PMCID: PMC10514296 DOI: 10.1038/s41522-023-00435-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 09/11/2023] [Indexed: 09/23/2023] Open
Abstract
The gut microbiota serves as a critical "organ" in the life cycle of animals, particularly in the intricate interplay between herbivorous pests and plants. This review summarizes the pivotal functions of the gut microbiota in mediating the insect-plant interactions, encompassing their influence on host insects, modulation of plant physiology, and regulation of the third trophic level species within the ecological network. Given these significant functions, it is plausible to harness these interactions and their underlying mechanisms to develop novel eco-friendly pest control strategies. In this context, we also outline some emerging pest control methods based on the intestinal microbiota or bacteria-mediated interactions, such as symbiont-mediated RNAi and paratransgenesis, albeit these are still in their nascent stages and confront numerous challenges. Overall, both opportunities and challenges coexist in the exploration of the intestinal microbiota-mediated interactions between insect pests and plants, which will not only enrich the fundamental knowledge of plant-insect interactions but also facilitate the development of sustainable pest control strategies.
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Affiliation(s)
- Yuxin Zhang
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, 430062, Wuhan, China
| | - Shouke Zhang
- State Key Laboratory of Subtropical Silviculture, Zhejiang A & F University, 311300, Hangzhou, China.
| | - Letian Xu
- State Key Laboratory of Biocatalysis and Enzyme Engineering, School of Life Sciences, Hubei University, 430062, Wuhan, China.
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Velásquez C. LF, Cantón PE, Sanchez-Flores A, Soberón M, Bravo A, Cerón S. JA. Identification of Cry toxin receptor genes homologs in a de novo transcriptome of Premnotrypes vorax (Coleoptera: Curculionidae). PLoS One 2023; 18:e0291546. [PMID: 37708134 PMCID: PMC10501650 DOI: 10.1371/journal.pone.0291546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 09/01/2023] [Indexed: 09/16/2023] Open
Abstract
The white potato worm Premnotrypes vorax (Hustache) (Coleoptera: Curculionidae) is one of the most destructive insect pests of potato crops in South America. Like many coleopteran insects, P. vorax shows low susceptibility to Cry insecticidal proteins produced by the bacterium Bacillus thuringiensis (Bt). However, the presence of Cry toxin receptors in the midgut of this this insect has never been studied. The main Cry-binding proteins described in other insect species are cadherin (CAD), aminopeptidase N (APN), alkaline phosphatase (ALP) and ATP-binding cassette (ABC) transporters. In this study, we analyzed and validated a de novo assembled transcriptome of Illumina sequencing data to identify and to characterize homologs of Cry toxin receptors. We identified the protein sequences in P. vorax that show high identity with their orthologous sequences of the Cry toxin binding proteins in other coleopteran larvae such as APN, ALP, CAD and ABC transporter. This study provides preliminary identification of putative receptor genes of Cry proteins that would be useful for future studies involving biocontrol of this important potato crop pest.
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Affiliation(s)
| | - Pablo Emiliano Cantón
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Alejandro Sanchez-Flores
- Unidad Universitaria de Secuenciación Masiva y Bioinformática, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Mario Soberón
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Alejandra Bravo
- Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Jairo A. Cerón S.
- Instituto de Biotecnología, Universidad Nacional de Colombia, Bogotá, Colombia
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Li K, Yu S, Yang Y, He YZ, Wu Y. Mechanisms of feeding cessation in Helicoverpa armigera larvae exposed to Bacillus thuringiensis Cry1Ac toxin. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2023; 195:105565. [PMID: 37666620 DOI: 10.1016/j.pestbp.2023.105565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 07/27/2023] [Accepted: 08/01/2023] [Indexed: 09/06/2023]
Abstract
Insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) have been applied in sprayable formulations and expressed in transgenic crops for the control of pests in the field. When exposed to Bt proteins insect larvae display feeding cessation, yet the mechanism for this phenomenon remains unknown. In this study, we investigated the feeding behavior and underlying mechanisms of cotton bollworm (Helicoverpa armigera) larvae after exposure to the Cry1Ac protein from Bt. Three H. armigera strains were studied: the susceptible SCD strain, the C2/3-KO strain with HaABCC2 and HaABCC3 knocked out and high-level resistance to Cry1Ac (>15,000-fold), and the SCD-KI strain with a T92C point mutation in tetraspanin (HaTSPAN1) and medium-level resistance to Cry1Ac (125-fold). When determining the percentage of insects that continued feeding after various exposure times to Cry1Ac, we observed quick cessation of feeding in larvae from the susceptible SCD strain, whereas larvae from the C2/3-KO strain did not display feeding cessation. In contrast, larvae from the SCD-KI strain rapidly recovered from the initial feeding cessation. Histopathological analyses and qRT-PCR in midguts of SCD larvae after Cry1Ac exposure detected serious epithelial damage and significantly reduced expression of the neuropeptide F gene (NPF) and its potential receptor gene NPFR, which are reported to promote insect feeding. Neither epithelial damage nor altered NPF and NPFR expression appeared in midguts of C2/3-KO larvae after Cry1Ac treatment. The same treatment in SCD-KI larvae resulted in milder epithelial damage and subsequent repair, and a decrease followed by an initial increase in NPF and NPFR expression. These results demonstrate that the feeding cessation response to Cry1Ac in cotton bollworm larvae is closely associated with midgut epithelial damage and downregulation of NPF and NPFR expression. This information provides clues to the mechanism of feeding cessation in response to Bt intoxication and contributes to the mode of action of the Cry1Ac toxin in target pests.
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Affiliation(s)
- Kaixia Li
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Shan Yu
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Yihua Yang
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Ya-Zhou He
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
| | - Yidong Wu
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China.
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40
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Wu Y, Weng Z, Yan H, Yao Z, Li Z, Sun Y, Ma K, Hull JJ, Zhang D, Ma W, Hua H, Lin Y. The microRNA-7322-5p/p38/Hsp19 axis modulates Chilo suppressalis cell-defences against Cry1Ca: an effective target for a stacked transgenic rice approach. PLANT BIOTECHNOLOGY JOURNAL 2023; 21:1827-1838. [PMID: 37353991 PMCID: PMC10440986 DOI: 10.1111/pbi.14095] [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: 01/25/2023] [Revised: 04/08/2023] [Accepted: 05/16/2023] [Indexed: 06/25/2023]
Abstract
Bacillus thuringiensis (Bt)-secreted crystal (Cry) toxins form oligomeric pores in host cell membranes and are a common element in generating insect-resistant transgenic crops. Although Cry toxin function has been well documented, cellular defences against pore-formation have not been as well developed. Elucidation of the processes underlying this defence, however, could contribute to the development of enhanced Bt crops. Here, we demonstrate that Cry1Ca-mediated downregulation of microRNA-7322-5p (miR-7322-5p), which binds to the 3' untranslated region of p38, negatively regulates the susceptibility of Chilo suppressalis to Cry1Ca. Moreover, Cry1Ca exposure enhanced phosphorylation of Hsp19, and hsp19 downregulation increased susceptibility to Cry1Ca. Further, Hsp19 phosphorylation occurs downstream of p38, and pull-down assays confirmed the interactions between Hsp19 and Cry1Ca, suggesting that activation of Hsp19 by the miR-7322-5p/p38/Hsp19 pathway promotes Cry1Ca sequestration. To assess the efficacy of targeting this pathway in planta, double-stranded RNA (dsRNA) targeting C. suppressalis p38 (dsp38) was introduced into a previously generated cry1Ca-expressing rice line (1CH1-2) to yield a single-copy cry1Ca/dsp38 rice line (p38-rice). Feeding on this rice line triggered a significant reduction in C. suppressalis p38 expression and the line was more resistant to C. suppressalis than 1CH1-2 in both short term (7-day) and continuous feeding bioassays as well as field trials. These findings provide new insights into invertebrate epithelium cellular defences and demonstrate a potential new pyramiding strategy for Bt crops.
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Affiliation(s)
- Yan Wu
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhanHubeiChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanHubeiChina
| | - Zijin Weng
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhanHubeiChina
- College of Life Science and TechnologyHuazhong Agricultural UniversityWuhanHubeiChina
| | - Haixia Yan
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhanHubeiChina
- College of Life Science and TechnologyHuazhong Agricultural UniversityWuhanHubeiChina
| | - Zhuotian Yao
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhanHubeiChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanHubeiChina
| | - Zhenzhen Li
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanHubeiChina
| | - Yajie Sun
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanHubeiChina
| | - Kangsheng Ma
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanHubeiChina
| | - J. Joe Hull
- U.S. Arid Land Agricultural Research Center, Department of AgricultureU.S. Agricultural Research ServiceMaricopaArizonaUSA
| | - Delin Zhang
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhanHubeiChina
- College of Life Science and TechnologyHuazhong Agricultural UniversityWuhanHubeiChina
| | - Weihua Ma
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhanHubeiChina
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanHubeiChina
| | - Hongxia Hua
- College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanHubeiChina
| | - Yongjun Lin
- National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research, Hubei Hongshan LaboratoryHuazhong Agricultural UniversityWuhanHubeiChina
- College of Life Science and TechnologyHuazhong Agricultural UniversityWuhanHubeiChina
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41
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Wei W, Wang L, Pan S, Wang H, Xia Z, Liu L, Xiao Y, Bravo A, Soberón M, Yang Y, Liu K. Helicoverpa armigera GATAe transcriptional factor regulates the expression of Bacillus thuringiensis Cry1Ac receptor gene ABCC2 by its interplay with additional transcription factors. PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY 2023; 194:105516. [PMID: 37532331 DOI: 10.1016/j.pestbp.2023.105516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 06/12/2023] [Accepted: 07/03/2023] [Indexed: 08/04/2023]
Abstract
Helicoverpa armigera is a worldwide pest that has been efficiently controlled by transgenic plants expressing Bt Cry toxins. To exert toxicity, Cry toxins bind to different receptors located in larval midgut cells. Previously, we reported that GATA transcription factor GATAe activates the expression of multiple H. armigera Cry1Ac receptors in different insect cell lines. Here, the mechanism involved in GATAe regulation of HaABCC2 gene expression, a key receptor of Cry1Ac, was analyzed. HaGATAe gene silencing by RNAi in H. armigera larvae confirmed the activation role of HaGATAe on the expression of HaABCC2 in the midgut. The contribution of all potential GATAe-binding sites was analyzed by site-directed mutagenesis using Hi5 cells expressing a reporter gene under regulation of different modified HaABCC2 promoters. DNA pull-down assays revealed that GATAe bound to different predicted GATA-binding sites and mutations of the different GATAe-binding sites identified two binding sites responsible for the promoter activity. The binding site B9, which is located near the transcription initiator site, has a major contribution on HaABCC2 expression. Also, DNA pull-down assays revealed that all other members of GATA TF family in H. armigera, besides GATAe, HaGATAa, HaGATAb, HaGATAc and HaGATAd also bound to the HaABCC2 promoter and decreased the GATAe dependent promoter activity. Finally, the potential participation in the regulation of HaABCC2 promoter of several TFs other than GATA TFs expressed in the midgut cells was analyzed. HaHR3 inhibited the GATAe dependent activity of the HaABCC2 promoter, while two other midgut-related TFs, HaCDX and HaSox21, also bound to the HaABCC2 promoter region and increased the GATAe dependent promoter activity. All these data showed that GATAe induces HaABCC2 expression by binding to HaGATAe binding sites in the promoter region and that additional TFs participate in modulating the HaGATAe-driven expression of HaABCC2.
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Affiliation(s)
- Wei Wei
- School of Life Sciences, Central China Normal University, Wuhan 430070, China; Applied Biotechnology Center, Wuhan University of Bioengineering, Wuhan 430415, China
| | - Ling Wang
- Institute of Hubei Agriculture Academy, Wuhan 430070, China
| | - Shuang Pan
- School of Life Sciences, Central China Normal University, Wuhan 430070, China
| | - Haixia Wang
- School of Life Sciences, Central China Normal University, Wuhan 430070, China
| | - Zhichao Xia
- School of Life Sciences, Central China Normal University, Wuhan 430070, China
| | - Leilei Liu
- School of Life Sciences, Central China Normal University, Wuhan 430070, China; Applied Biotechnology Center, Wuhan University of Bioengineering, Wuhan 430415, China
| | - Yutao Xiao
- Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
| | - Alejandra Bravo
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca 62250, Morelos, Mexico
| | - Mario Soberón
- Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, Cuernavaca 62250, Morelos, Mexico
| | - Yongbo Yang
- School of Life Sciences, Central China Normal University, Wuhan 430070, China.
| | - Kaiyu Liu
- School of Life Sciences, Central China Normal University, Wuhan 430070, China.
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Chen W, Amir MB, Liao Y, Yu H, He W, Lu Z. New Insights into the Plutella xylostella Detoxifying Enzymes: Sequence Evolution, Structural Similarity, Functional Diversity, and Application Prospects of Glucosinolate Sulfatases. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:10952-10969. [PMID: 37462091 PMCID: PMC10375594 DOI: 10.1021/acs.jafc.3c03246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/27/2023]
Abstract
Brassica plants have glucosinolate (GLs)-myrosinase defense mechanisms to deter herbivores. However, Plutella xylostella specifically feeds on Brassica vegetables. The larvae possess three glucosinolate sulfatases (PxGSS1-3) that compete with plant myrosinase for shared GLs substrates and produce nontoxic desulfo-GLs (deGLs). Although PxGSSs are considered potential targets for pest control, the lack of a comprehensive review has hindered the development of PxGSSs-targeted pest control methods. Recent advances in integrative multi-omics analysis, substrate-enzyme kinetics, and molecular biological techniques have elucidated the evolutionary origin and functional diversity of these three PxGSSs. This review summarizes research progress on PxGSSs over the past 20 years, covering sequence properties, evolution, protein modification, enzyme activity, structural variation, substrate specificity, and interaction scenarios based on functional diversity. Finally, we discussed the potential applications of PxGSSs-targeted pest control technologies driven by artificial intelligence, including CRISPR/Cas9-mediated gene drive, transgenic plant-mediated RNAi, small-molecule inhibitors, and peptide inhibitors. These technologies have the potential to overcome current management challenges and promote the development and field application of PxGSSs-targeted pest control.
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Affiliation(s)
- Wei Chen
- Ganzhou Key Laboratory of Greenhouse Vegetable, School of Life Sciences, Gannan Normal University, Ganzhou 341000, China
| | - Muhammad Bilal Amir
- Ganzhou Key Laboratory of Greenhouse Vegetable, School of Life Sciences, Gannan Normal University, Ganzhou 341000, China
- South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
| | - Yuan Liao
- Ganzhou Key Laboratory of Greenhouse Vegetable, School of Life Sciences, Gannan Normal University, Ganzhou 341000, China
| | - Haizhong Yu
- Ganzhou Key Laboratory of Greenhouse Vegetable, School of Life Sciences, Gannan Normal University, Ganzhou 341000, China
| | - Weiyi He
- State Key Laboratory for Ecological Pest Control of Fujian and Taiwan Crops, International Joint Research Laboratory of Ecological Pest Control, Fujian Agriculture and Forestry University, Fuzhou 350002, China
| | - Zhanjun Lu
- Ganzhou Key Laboratory of Greenhouse Vegetable, School of Life Sciences, Gannan Normal University, Ganzhou 341000, China
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Morwool P, Dimitriu T, Crickmore N, Raymond B. Group Selection as a Basis for Screening Mutagenized Libraries of Public Goods (Bacillus thuringiensis Cry Toxins). Appl Environ Microbiol 2023; 89:e0051223. [PMID: 37358425 PMCID: PMC10370297 DOI: 10.1128/aem.00512-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 05/26/2023] [Indexed: 06/27/2023] Open
Abstract
The pesticidal toxins of Bacillus thuringiensis (Bt) supply the active proteins for genetically modified insect-resistant crops. There is therefore keen interest in finding new toxins, or improving known toxins, in order to increase the mortality of various targets. The production and screening of large libraries of mutagenized toxins are among the means of identifying improved toxins. Since Cry toxins are public goods, and do not confer advantages to producers in competition, conventional directed evolution approaches cannot be used here. Instead, thousands of individual mutants have to be sequenced and assayed individually, a costly and time-consuming process. In this study, we tested a group selection-based approach that could be used to screen an uncharacterized pool of Cry toxin mutants. This involved selecting for infectivity between subpopulations of Bt clones within metapopulations of infected insects in three rounds of passage. We also tested whether additional mutagenesis from exposure to ethyl methanesulfonate could increase infectivity or supply additional Cry toxin diversity during passage. Sequencing of pools of mutants at the end of selection showed that we could effectively screen out Cry toxin variants that had reduced toxicity with our group selection approach. The addition of extra mutagenesis during passage decreased the efficiency of selection for infectivity and did not produce any additional novel toxin diversity. Toxins with loss-of-function mutations tend to dominate mutagenized libraries, and so a process for screening out these mutants without time-consuming sequencing and characterization steps could be beneficial when applied to larger libraries. IMPORTANCE Insecticidal toxins from the bacterium Bacillus thuringiensis are widely exploited in genetically modified plants. This application creates a demand for novel insecticidal toxins that can be used to better manage resistant pests or control new or recalcitrant target species. An important means of producing novel toxins is via high-throughput mutagenesis and screening of existing toxins, a lengthy and resource-intensive process. This study describes the development and testing of an efficient means of screening a test library of mutagenized insecticidal toxins. Here, we showed that it is possible to screen out loss-of-function mutations with low infectivity within a pool without the need to characterize and sequence each mutant individually. This has the potential to improve the efficiency of processes used to identify novel proteins.
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Affiliation(s)
| | | | - Neil Crickmore
- Department of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Ben Raymond
- University of Exeter, Penryn, United Kingdom
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Naing ZL, Soe ET, Zhang C, Niu L, Tang J, Ding Z, Yu S, Lu J, Fang F, Liang G. Cadherin Is a Binding Protein but Not a Functional Receptor of Bacillus thuringiensis Cry2Ab in Helicoverpa armigera. Appl Environ Microbiol 2023; 89:e0062523. [PMID: 37378519 PMCID: PMC10370303 DOI: 10.1128/aem.00625-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 05/29/2023] [Indexed: 06/29/2023] Open
Abstract
Midgut receptors play a critical role in the specificity of Cry toxins for individual insect species. Cadherin proteins are essential putative receptors of Cry1A toxins in lepidopteran larvae. Cry2A family members share common binding sites in Helicoverpa armigera, and one of them, Cry2Aa, has been widely reported to interact with midgut cadherin. Here, we studied the binding interaction and functional role of H. armigera cadherin in the mechanism of Cry2Ab toxicity. A region spanning from cadherin repeat 6 (CR6) to the membrane-proximal region (MPR) of cadherin protein was produced as six overlapping peptides to identify the specific binding regions of Cry2Ab. Binding assays showed that Cry2Ab binds nonspecifically to peptides containing CR7 and CR11 regions in a denatured state but binds specifically only to CR7-containing peptides in the native state. The peptides CR6-11 and CR6-8 were transiently expressed in Sf9 cells to assess the functional role of cadherin. Cytotoxicity assays showed that Cry2Ab is not toxic to the cells expressing any of the cadherin peptides. However, ABCA2-expressing cells showed high sensitivity to Cry2Ab toxin. Neither increased nor decreased sensitivity to Cry2Ab was observed when the peptide CR6-11 was coexpressed with the ABCA2 gene in Sf9 cells. Instead, treating ABCA2-expressing cells with a mixture of Cry2Ab and CR6-8 peptides resulted in significantly reduced cell death compared with treatment with Cry2Ab alone. Moreover, silencing of the cadherin gene in H. armigera larvae showed no significant effect on Cry2Ab toxicity, in contrast to the reduced mortality in ABCA2-silenced larvae. IMPORTANCE To improve the efficiency of production of a single toxin in crops and to delay the evolution of insect resistance to the toxin, the second generation of Bt cotton, expressing Cry1Ac and Cry2Ab, was introduced. Understanding the mode action of the Cry proteins in the insect midgut and the mechanisms insects use to overcome these toxins plays a crucial role in developing measures to counter them. Extensive studies have been conducted on the receptors of Cry1A toxins, but relatively little has been done about those of Cry2Ab. By showing the nonfunctional binding of cadherin protein with Cry2Ab, we have furthered the understanding of Cry2Ab receptors.
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Affiliation(s)
- Zaw Lin Naing
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Ei Thinzar Soe
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Caihong Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Linlin Niu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Jinrong Tang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Zhongwei Ding
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Siqi Yu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Jie Lu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Fengyun Fang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
| | - Gemei Liang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, People’s Republic of China
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45
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Dively GP, Kuhar TP, Taylor SV, Doughty H, Holmstrom K, Gilrein DO, Nault BA, Ingerson-Mahar J, Huseth A, Reisig D, Fleischer S, Owens D, Tilmon K, Reay-Jones F, Porter P, Smith J, Saguez J, Wells J, Congdon C, Byker H, Jensen B, DiFonzo C, Hutchison WD, Burkness E, Wright R, Crossley M, Darby H, Bilbo T, Seiter N, Krupke C, Abel C, Coates BS, McManus B, Fuller B, Bradshaw J, Peterson JA, Buntin D, Paula-Moraes S, Kesheimer K, Crow W, Gore J, Huang F, Ludwick DC, Raudenbush A, Jimenez S, Carrière Y, Elkner T, Hamby K. Extended Sentinel Monitoring of Helicoverpa zea Resistance to Cry and Vip3Aa Toxins in Bt Sweet Corn: Assessing Changes in Phenotypic and Allele Frequencies of Resistance. INSECTS 2023; 14:577. [PMID: 37504584 PMCID: PMC10380249 DOI: 10.3390/insects14070577] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 06/12/2023] [Accepted: 06/14/2023] [Indexed: 07/29/2023]
Abstract
Transgenic corn and cotton that produce Cry and Vip3Aa toxins derived from Bacillus thuringiensis (Bt) are widely planted in the United States to control lepidopteran pests. The sustainability of these Bt crops is threatened because the corn earworm/bollworm, Helicoverpa zea (Boddie), is evolving a resistance to these toxins. Using Bt sweet corn as a sentinel plant to monitor the evolution of resistance, collaborators established 146 trials in twenty-five states and five Canadian provinces during 2020-2022. The study evaluated overall changes in the phenotypic frequency of resistance (the ratio of larval densities in Bt ears relative to densities in non-Bt ears) in H. zea populations and the range of resistance allele frequencies for Cry1Ab and Vip3Aa. The results revealed a widespread resistance to Cry1Ab, Cry2Ab2, and Cry1A.105 Cry toxins, with higher numbers of larvae surviving in Bt ears than in non-Bt ears at many trial locations. Depending on assumptions about the inheritance of resistance, allele frequencies for Cry1Ab ranged from 0.465 (dominant resistance) to 0.995 (recessive resistance). Although Vip3Aa provided high control efficacy against H. zea, the results show a notable increase in ear damage and a number of surviving older larvae, particularly at southern locations. Assuming recessive resistance, the estimated resistance allele frequencies for Vip3Aa ranged from 0.115 in the Gulf states to 0.032 at more northern locations. These findings indicate that better resistance management practices are urgently needed to sustain efficacy the of corn and cotton that produce Vip3Aa.
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Affiliation(s)
- Galen P Dively
- Department of Entomology, University of Maryland, College Park, MD 20742, USA
| | - Tom P Kuhar
- Department of Entomology, Virginia Tech, Blacksburg, VA 24060, USA
| | - Sally V Taylor
- Department of Entomology, Virginia Tech, Suffolk, VA 23434, USA
| | | | - Kristian Holmstrom
- Pest Management Office, Rutgers University, New Brunswick, NJ 08901, USA
| | | | - Brian A Nault
- Department of Entomology, Cornell AgriTech, Geneva, NY 14456, USA
| | - Joseph Ingerson-Mahar
- Rutgers Agricultural Research and Extension Center, Rutgers University, Bridgeton, NJ 08302, USA
| | - Anders Huseth
- Department of Entomology and Plant Pathology, NC State University, Raleigh, NC 27601, USA
| | - Dominic Reisig
- Department of Entomology and Plant Pathology, NC State University, Plymouth, NC 27962, USA
| | - Shelby Fleischer
- Department of Entomology, Penn State University, University Park, PA 16802, USA
| | - David Owens
- Cooperative Extension, Carvel REC, University of Delaware, Georgetown, DE 19947, USA
| | - Kelley Tilmon
- Ohio Agricultural Research and Development Center, Wooster, OH 44691, USA
| | - Francis Reay-Jones
- Department of Plant and Environmental Sciences, Clemson University, Florence, SC 29501, USA
| | - Pat Porter
- Department of Entomology, AgriLife Research and Extension Center, Texas A&M University, Lubbock, TX 79401, USA
| | - Jocelyn Smith
- Department of Plant Agriculture, University of Guelph, Ridgetown Campus, ON N1G 2W1, Canada
| | - Julien Saguez
- CEROM, 740 Chemin Trudeau, Saint-Mathieu-de-Beloeil, QC J3G 0E2, Canada
| | - Jason Wells
- New Brunswick Department of Agriculture, Sussex, NB E4E 5L8, Canada
| | - Caitlin Congdon
- Perennia Food and Agriculture, Kentville, NS B4N 1J5, Canada
| | - Holly Byker
- Department of Plant Agriculture, University of Guelph, Winchester, ON N1G 2W1, Canada
| | - Bryan Jensen
- Arlington Agricultural Research Station, University of Wisconsin, WI 53706, USA
| | - Chris DiFonzo
- Department of Entomology, Michigan State University, East Lansing, MI 48824, USA
| | | | - Eric Burkness
- Department of Entomology, University of Minnesota, St. Paul, MN 55455, USA
| | - Robert Wright
- Department of Entomology, University of Nebraska-Lincoln, NE 68588, USA
| | - Michael Crossley
- Department of Entomology and Wildlife Ecology, University of Delaware, Newark, DE 19711, USA
| | - Heather Darby
- Department of Plant and Soil Sciences, University of Vermont, Burlington, VT 05405, USA
| | - Tom Bilbo
- Department of Plant and Environmental Sciences, Clemson University, Charleston, SC 29414, USA
| | - Nicholas Seiter
- Illinois Extension, University of Illinois, Urbana, IL 61820, USA
| | - Christian Krupke
- Department of Entomology, Purdue University, West Lafayette, IN 47906, USA
| | - Craig Abel
- USDA-ARS Corn Insects and Crop Genetics Research, Iowa State University, Ames, IA 50011, USA
| | - Brad S Coates
- USDA-ARS Corn Insects and Crop Genetics Research, Iowa State University, Ames, IA 50011, USA
| | | | | | - Jeffrey Bradshaw
- Panhandle Research and Extension Center, Scottsbluff, NE 69361, USA
| | - Julie A Peterson
- West Central Research and Extension Center, University of Nebraska, North Platte, NE 69101, USA
| | - David Buntin
- Griffin Campus, University of Georgia, Griffin, GA 30223, USA
| | | | - Katelyn Kesheimer
- Department of Entomology & Plant Pathology, Auburn University, Auburn, AL 36849, USA
| | - Whitney Crow
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Delta Research and Extension Center, Mississippi State University, Stoneville, MS 39762, USA
| | - Jeffrey Gore
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Delta Research and Extension Center, Mississippi State University, Stoneville, MS 39762, USA
| | - Fangneng Huang
- Department of Entomology, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Dalton C Ludwick
- Department of Entomology, Texas A&M AgriLife Extension Service, Corpus Christi, TX 78404, USA
| | - Amy Raudenbush
- Ohio Agricultural Research and Development Center, Wooster, OH 44691, USA
| | - Sebastian Jimenez
- PEI Department of Agriculture and Land, Charlotte, PE C1A 7N8, Canada
| | - Yves Carrière
- Department of Entomology, University of Arizona, Tucson, AZ 85721, USA
| | - Timothy Elkner
- Southeast Research and Extension Center, Landisville, PA 17538, USA
| | - Kelly Hamby
- Department of Entomology, University of Maryland, College Park, MD 20742, USA
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46
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Jin M, Shan Y, Li Q, Peng Y, Xiao Y. A novel Cry1A resistance allele of fall armyworm in the new invaded region. Int J Biol Macromol 2023; 244:125392. [PMID: 37321433 DOI: 10.1016/j.ijbiomac.2023.125392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/09/2023] [Accepted: 06/12/2023] [Indexed: 06/17/2023]
Abstract
The fall armyworm, Spodoptera frugiperda, is a devastating pest in its native range Western Hemisphere and has become a major invasive pest around the globe. Transgenic crops producing Bt toxins have been widely used to control S. frugiperda. However, the evolution of resistance threatens the sustainability of Bt crops. Field-evolved S. frugiperda resistance to Bt crops was observed in America, whereas, no case of field-resistance was reported in its newly invaded East Hemisphere. Here we investigated the molecular mechanism of a Cry1Ab-resistant LZ-R strain of S. frugiperda, which selected 27-generations using Cry1Ab after being collected in corn fields from China. Complementation tests between LZ-R strain and SfABCC2-KO strain, which have been knockout SfABCC2 gene and confer 174-fold resistance to Cry1Ab, showed a similar level of resistance in the F1-progeny as their parent stains, indicating that a common locus of SfABCC2 mutation in LZ-R stain. Sequencing of the full length of SfABCC2 cDNA from LZ-R strain, we characterize a novel mutation allele of SfABCC2. Cross-resistance results showed that Cry1Ab-resistance strain also confers >260-fold resistance to Cry1F, with no cross-resistance to Vip3A. These results provided evidence of a novel SfABCC2 mutation allele in the newly invaded East Hemisphere of S. frugiperda.
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Affiliation(s)
- Minghui Jin
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies (Hainan), Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Yinxue Shan
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies (Hainan), Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Qi Li
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies (Hainan), Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Yan Peng
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies (Hainan), Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China
| | - Yutao Xiao
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Gene Editing Technologies (Hainan), Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China.
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47
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Panteleri R, Anthousi A, Denecke S, Boaventura D, Nauen R, Vontas J. Transgenic Drosophila to Functionally Validate Fall Armyworm ABCC2 Mutations Conferring Bt Resistance. Toxins (Basel) 2023; 15:386. [PMID: 37368687 DOI: 10.3390/toxins15060386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 06/05/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith; Lepidoptera: Noctuidae) is an invasive agricultural pest with a global distribution, causing major crop losses annually. Its control strategies largely rely on chemical insecticides and transgenic crops expressing Bacillus thuringiensis insecticidal proteins (Cry and Vip toxins); however, the development of high resistance poses a significant issue. The ATP-binding cassette transporter C2 (ABCC2) has been linked to Cry toxin pore formation, acting as a receptor of some Cry toxins. Recently detected mutations in the SfABCC2 gene in extracellular loop 4 (ECL4) have been associated with Bt toxin resistance in FAW. In the present study, we expressed the SfABCC2 gene in Drosophila melanogaster, a species normally unaffected by the Bt toxins. We demonstrate that susceptibility can be introduced by the ectopic and tissue-specific expression of wildtype SfABCC2. Next, we introduced mutations into ECL4-both individually and in combination-that have been recently described in Brazilian FAW and functionally validated by toxicity bioassays against the foliar Bt product Xentari. Our results provide an efficient demonstration of the suitability of transgenic Drosophila for validating FAW ABCC2 resistance mutations in ECL4 against Bt toxins, and potential cross-resistance issues between closely related proteins that use ABCC2.
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Affiliation(s)
- Rafaela Panteleri
- Department of Biology, University of Crete, Vassilika Vouton, 71409 Heraklion, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, 71409 Heraklion, Greece
| | - Amalia Anthousi
- Department of Biology, University of Crete, Vassilika Vouton, 71409 Heraklion, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, 71409 Heraklion, Greece
| | - Shane Denecke
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, 71409 Heraklion, Greece
- Department of Pathobiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Debora Boaventura
- Bayer AG, Crop Science Division, R&D, Pest Control, 40789 Monheim, Germany
| | - Ralf Nauen
- Bayer AG, Crop Science Division, R&D, Pest Control, 40789 Monheim, Germany
| | - John Vontas
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, 71409 Heraklion, Greece
- Pesticide Science Laboratory, Department of Crop Science, Agricultural University of Athens, Iera Odos 75, 11855 Athens, Greece
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48
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Farhan Y, Smith JL, Sovic MG, Michel AP. Genetic mutations linked to field-evolved Cry1Fa-resistance in the European corn borer, Ostrinia nubilalis. Sci Rep 2023; 13:8081. [PMID: 37202428 DOI: 10.1038/s41598-023-35252-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 05/15/2023] [Indexed: 05/20/2023] Open
Abstract
Transgenic corn, Zea mays (L.), expressing insecticidal toxins such as Cry1Fa, from Bacillus thuringiensis (Bt corn) targeting Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae) resulted in over 20 years of management success. The first case of practical field-evolved resistance by O. nubilalis to a Bt corn toxin, Cry1Fa, was discovered in Nova Scotia, Canada, in 2018. Laboratory-derived Cry1Fa-resistance by O. nubilalis was linked to a genome region encoding the ATP Binding Cassette subfamily C2 (ABCC2) gene; however, the involvement of ABCC2 and specific mutations in the gene leading to resistance remain unknown. Using a classical candidate gene approach, we report on O. nubilalis ABCC2 gene mutations linked to laboratory-derived and field-evolved Cry1Fa-resistance. Using these mutations, a DNA-based genotyping assay was developed to test for the presence of the Cry1Fa-resistance alleles in O. nubilalis strains collected in Canada. Screening data provide strong evidence that field-evolved Cry1Fa-resistance in O. nubilalis maps to the ABCC2 gene and demonstrates the utility of this assay for detecting the Cry1Fa resistance allele in O. nubilalis. This study is the first to describe mutations linked to Bt resistance in O. nubilalis and provides a DNA-based detection method that can be used for monitoring.
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Affiliation(s)
- Yasmine Farhan
- Department of Plant Agriculture, University of Guelph, Ridgetown Campus, Ridgetown, ON, Canada.
| | - Jocelyn L Smith
- Department of Plant Agriculture, University of Guelph, Ridgetown Campus, Ridgetown, ON, Canada
| | - Michael G Sovic
- Infectious Diseases Institute, The Ohio State University, Pickerington, OH, USA
| | - Andrew P Michel
- Department of Entomology, The Ohio State University, Wooster, OH, USA
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49
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Hwang HS, Acharya R, Lucas MDC, Sharma SR, Lee YS, Lee KY. Effects of Lymantria dispar multiple nucleopolyhedrovirus and Bacillus thuringiensis var. kurstaki on different larval instars of Lymantria dispar asiatica. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2023; 113:e22002. [PMID: 36662511 DOI: 10.1002/arch.22002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 12/28/2022] [Accepted: 01/12/2023] [Indexed: 06/17/2023]
Abstract
Outbreaks of Lymantria dispar asiatica (the Asian spongy moth; Lepidoptera: Erebidae) occur sporadically, causing widespread damage to forest and fruit trees. Owing to the development of pesticide resistance and environmental contamination, biopesticides, including L. dispar multiple nucleopolyhedrovirus (LdMNPV) and Bacillus thuringiensis var. kurstaki (Btk), can significantly contribute to controlling overall larval stage of this species. Although both pathogens are highly effective at the larval stage, their effects on different instar stages have not been investigated. In this study, we analyzed the mortality and lethality in different L. dispar asiatica instars exposed to single or combined pathogen treatments. Treatments with low or medium LdMNPV concentrations induced lower mortality and had higher LT50 values at the 4th and 5th instars compared with other instars, whereas high LdMNPV treatments induced high mortality in all instars, with higher LT50 values at later instars. Treatment with Btk induced a rapid 100% mortality in all instars, with higher LT50 values for the later instars. The combination of LdMNPV and Btk delayed the killing time compared with the effects of single treatments, with the effect being more pronounced in the 1st and 5th instar stage than at other stages at low Btk concentrations. Our findings indicate that the pathogenic effects of LdMNPV and Btk on L. dispar asiatica differ according to larval stage, thereby providing novel insights into enhancing the biological control efficacy of these agents against L. dispar asiatica in the field.
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Affiliation(s)
- Hwal-Su Hwang
- College of Agriculture and Life Sciences, Kyungpook National University, Daegu, Republic of Korea
| | - Rajendra Acharya
- College of Agriculture and Life Sciences, Kyungpook National University, Daegu, Republic of Korea
| | | | - Sushant Raj Sharma
- College of Agriculture and Life Sciences, Kyungpook National University, Daegu, Republic of Korea
| | - Young-Su Lee
- Gyeonggi Agricultural Research and Extension Services, Hwaseong, Republic of Korea
| | - Kyeong-Yeoll Lee
- College of Agriculture and Life Sciences, Kyungpook National University, Daegu, Republic of Korea
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50
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Guan F, Dai X, Yang Y, Tabashnik BE, Wu Y. Population Genomics of Nonrecessive Resistance to Bt Toxin Cry1Ac in Helicoverpa armigera From Northern China. JOURNAL OF ECONOMIC ENTOMOLOGY 2023; 116:310-320. [PMID: 36610305 DOI: 10.1093/jee/toac182] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Indexed: 05/30/2023]
Abstract
Transgenic crops that produce insecticidal proteins from Bacillus thuringiensis (Bt) have provided control of some key pests since 1996. However, the evolution of resistance by pests reduces the benefits of Bt crops. Resistance to Bt crops that is not recessively inherited is especially challenging to manage. Here we analyzed nonrecessive resistance to Bt toxin Cry1Ac in eight field populations of Helicoverpa armigera sampled in 2018 from northern China, where this global pest has been exposed to Cry1Ac in Bt cotton since 1997. Bioassays revealed 7.5% of field-derived larvae were resistant to Cry1Ac of which 87% had at least one allele conferring nonrecessive resistance. To analyze this nonrecessive resistance, we developed and applied a variant of a genomic mapping approach called quantitative trait locus (QTL)-seq. This analysis identified a region on chromosome 10 associated with nonrecessive resistance to Cry1Ac in all 21 backcross families derived from field-collected moths. Individual sequencing revealed that all 21 field-collected resistant grandparents of the backcross families had a previously identified dominant point mutation in the tetraspanin gene HaTSPAN1 that occurs in the region of chromosome 10 identified by QTL-seq. QTL-seq also revealed a region on chromosome 26 associated with nonrecessive resistance in at most 14% of the backcross families. Overall, the results imply the point mutation in HaTSPAN1 is the primary genetic basis of nonrecessive resistance to Cry1Ac in field populations of H. armigera from northern China. Moreover, because nonrecessive resistance is predominant, tracking the frequency of this point mutation could facilitate resistance monitoring in the region.
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Affiliation(s)
- Fang Guan
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Xiaoguang Dai
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Yihua Yang
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Bruce E Tabashnik
- Department of Entomology, University of Arizona, Tucson, AZ 85721, USA
| | - Yidong Wu
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
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