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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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Lin M, Liu Y, Shen C, Meng M, Zhang X, Xu C, Jin J, Hu X, Zhu Q, Xie Y, Chen W, Liu X, Lin J. Generation of anti-idiotypic antibodies mimicking Cry2Aa toxin from an immunized mouse phage display library as potential insecticidal agents against Plutella xylostella. Biochem Biophys Res Commun 2024; 691:149308. [PMID: 38029542 DOI: 10.1016/j.bbrc.2023.149308] [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: 08/22/2023] [Revised: 11/18/2023] [Accepted: 11/20/2023] [Indexed: 12/01/2023]
Abstract
This study tried to generate anti-idiotypic antibodies (Ab2s) which mimic Cry2Aa toxin using a phage-display antibody library (2.8 × 107 CFU/mL). The latter was constructed from a mouse immunized with F (ab')2 fragments digested from anti-Cry2Aa polyclonal antibodies. The F (ab')2 fragments and Plutella xylostella (P. xylostella) brush border membrane vesicles (BBMV) were utilized as targets for selection. Eight mouse phage-display single-chain variable fragments (scFvs) were isolated and identified by enzyme-linked immunoassay (ELISA), PCR and DNA sequencing after four rounds of biopanning. Among them, M3 exhibited the highest binding affinity with F (ab')2, while M4 bound the best with the toxin binding region of cadherin of P. xylostella (PxCad-TBR). Both of these two fragments were chosen for prokaryotic expression. The expressed M3 and M4 proteins with molecular weights of 30 kDa were purified. The M4 showed a binding affinity of 29.9 ± 2.4 nM with the PxCad-TBR and resulted in 27.8 ± 4.3 % larvae mortality against P. xylostella. Computer-assisted molecular modeling and docking analysis showed that mouse scFv M4 mimicked some Cry2Aa toxin binding sites when interacting with PxCad-TBR. Therefore, anti-idiotypic antibodies generated by BBMV-based screening could be useful for the development of new bio-insecticides as an alternative to Cry2Aa toxin for pest control.
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Affiliation(s)
- Manman Lin
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality (Ministry of Agriculture), Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; School of Life Sciences, Discipline of Microbiology, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban, 4000, South Africa
| | - Yuan Liu
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality (Ministry of Agriculture), 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.
| | - Cheng Shen
- College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China
| | - Meng Meng
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Xiao Zhang
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality (Ministry of Agriculture), 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, Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality (Ministry of Agriculture), Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Jiafeng Jin
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Xiaodan Hu
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality (Ministry of Agriculture), Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; School of Life Sciences, Discipline of Microbiology, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban, 4000, South Africa
| | - Qing Zhu
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality (Ministry of Agriculture), Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China
| | - Yajing Xie
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality (Ministry of Agriculture), Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China; School of Life Sciences, Discipline of Microbiology, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban, 4000, South Africa
| | - Wei Chen
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base of Ministry of Science and Technology, Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality (Ministry of Agriculture), 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, Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality (Ministry of Agriculture), Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing, 210014, China.
| | - Johnson Lin
- School of Life Sciences, Discipline of Microbiology, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban, 4000, South Africa.
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Arsov A, Gerginova M, Paunova-Krasteva T, Petrov K, Petrova P. Multiple cry Genes in Bacillus thuringiensis Strain BTG Suggest a Broad-Spectrum Insecticidal Activity. Int J Mol Sci 2023; 24:11137. [PMID: 37446315 DOI: 10.3390/ijms241311137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 07/03/2023] [Accepted: 07/04/2023] [Indexed: 07/15/2023] Open
Abstract
The properties of Bacillus thuringiensis strains as a biopesticide with potent action against moths, beetles, and mosquitoes have been known for decades, with individual subspecies showing specific activity against a particular pest. The aim of the present work is to characterize strains that can be used for broad-spectrum pest control in agriculture. Twenty strains of B. thuringiensis were isolated from Bulgarian soil habitats. The strains were screened for genes encoding 12 different crystal (Cry) endotoxins by PCR with specific primer pairs. Seven of the isolates contained cry genes in their genomes. B. thuringiensis strains PL1, PL3, and PL20 contained at least three different cry genes, while B. thuringiensis serovar galleriae BTG contained at least four. Moreover, scanning electron microscopy (SEM) investigation revealed the production of bipyramidal (PL1, PL3, PL20), polygonal (PL1), cubic (BTG), and spherical crystals (BTG and PL20). Potentially containing the most cry genes, the BTG genome was sequenced and annotated. It comprises 6,275,416 base pairs, does not contain plasmids, has a GC content of 35.05%, and contained 7 genes encoding crystal toxins: cry1Ab35, cry1Db, cry1Fb, cry1Ib, cry2Ab, cry8Ea1, and cry9Ba. This unique combination would possibly enable the simultaneous pesticidal action against pest species from orders Lepidoptera, Coleoptera, Diptera, and Hemiptera, as well as class Gastropoda. Whole-genome sequencing provided accurate information about the presence, localization, and classification of Cry toxins in B. thuringiensis BTG, revealing the great potential of the strain for the development of new broad-spectrum bio-insecticides.
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Affiliation(s)
- Alexander Arsov
- Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Maria Gerginova
- Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | | | - Kaloyan Petrov
- Institute of Chemical Engineering, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Penka Petrova
- Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
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Yang X, Wang Z, Geng L, Chi B, Liu R, Li H, Gao J, Zhang J. Vip3Aa domain IV and V mutants confer higher insecticidal activity against Spodoptera frugiperda and Helicoverpa armigera. PEST MANAGEMENT SCIENCE 2022; 78:2324-2331. [PMID: 35243758 DOI: 10.1002/ps.6858] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 02/23/2022] [Accepted: 03/03/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND The fall armyworm Spodoptera frugiperda and cotton bollworm Helicoverpa armigera are major insect pests of corn and cotton worldwide. Genetically engineered crops producing Vip3Aa, a potent endotoxin, from the bacterium Bacillus thuringiensis (Bt) are effective in controlling these two harmful pests. However, Vip3Aa efficacy is relatively weak compared to that of other Bt proteins such as Cry1A and Cry1F. This study sought to modify Vip3Aa for increased insecticidal activity and determine the cause of elevated activity. RESULTS The two triple Vip3Aa mutants in domains IV and V (Vip3Aa-S543N/I544L/E627A and Vip3Aa-S543N/I544L/S686R) exhibited 7.3-fold and 2.8-fold increased toxicity against S. frugiperda, respectively, compared with the wild type while the toxicity of Vip3Aa-S543N/I544L/S686R was 3.2 times that of wild-type protein in H. armigera. The mutants had enhanced stability in midgut juice and 2.6-5.1 times higher binding affinity against S. frugiperda and H. armigera compared with wild type protein. CONCLUSIONS The enhanced toxicity of Vip3Aa mutants was due to increased stability and binding affinity during infection. The amino acids S543 and I544 combined with E627 or S686 in domains IV and V of Vip3Aa are important for maintaining structural stability and receptor binding. The results match insecticidal activity (LC50 ) with binding activity (Kd ), which provides novel clues for the rational design of Bt insecticidal proteins. © 2022 Society of Chemical Industry.
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Affiliation(s)
- Xiaoxue Yang
- Northeast Agricultural University, Harbin, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zeyu Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Lili Geng
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Baoyan Chi
- Northeast Agricultural University, Harbin, China
| | - Rongmei Liu
- Northeast Agricultural University, Harbin, China
| | - Haitao Li
- Northeast Agricultural University, Harbin, China
| | - Jiguo Gao
- Northeast Agricultural University, Harbin, China
| | - Jie Zhang
- Northeast Agricultural University, Harbin, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
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Cao D, Xiao C, Fu Q, Liu X, Liu R, Li H, Gao J. The Combination Analysis Between Bacillus thuringiensis Sip1Ab Protein and Brush Border Membrane Vesicles in Midgut of Colaphellus bowringi Baly. Front Microbiol 2022; 12:802035. [PMID: 35250907 PMCID: PMC8895204 DOI: 10.3389/fmicb.2021.802035] [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: 10/26/2021] [Accepted: 12/29/2021] [Indexed: 11/23/2022] Open
Abstract
The secretory insecticidal protein Sip1Ab and crystal protein Cry8Ca from Bacillus thuringiensis (Bt) are widely recognized for their coleopteran insecticidal activities. It is worthwhile to investigate the insecticidal mechanisms of these two proteins against Colaphellus bowringi Baly, which is a serious pest of cruciferous vegetables in China and other Asian countries. To that end, the genes encoding the Sip1Ab and Cry8Ca proteins were amplified from the strain QZL38 genome, then expressed in Escherichia coli, after which bioassays were conducted in C. bowringi larvae. After feeding these two proteins, the histopathological changes in the midguts of C. bowringi larvae were observed using transmission electron microscopy (TEM), and the Brush Border Membrane Vesicle (BBMV) was extracted for competition binding assays. TEM showed that ingestion of Sip1Ab caused a significant reduction in growth of the larvae, disruption of midgut microvilli, and expansion of intercellular spaces. Competition binding assays demonstrated that Sip1Ab bound to C. bowringi BBMV with a high binding affinity. However, a mixture of the two proteins in equal proportions showed no significant difference in insecticidal activity from that of Sip1Ab. These results could provide a molecular basis for the application of Sip1Ab in coleopteran insect control and contribute to the study of the Sip1Ab insecticidal mechanism as well.
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Affiliation(s)
- Dengtian Cao
- College of Life Sciences, Northeast Agricultural University, Harbin, China
| | - Changyixin Xiao
- College of Life Sciences, Northeast Agricultural University, Harbin, China
| | - Qian Fu
- College of Life Sciences, Northeast Agricultural University, Harbin, China
| | - Xinbo Liu
- College of Life Sciences, Northeast Agricultural University, Harbin, China
| | - Rongmei Liu
- College of Life Sciences, Northeast Agricultural University, Harbin, China
| | - Haitao Li
- College of Life Sciences, Northeast Agricultural University, Harbin, China
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
- *Correspondence: Haitao Li,
| | - Jiguo Gao
- College of Life Sciences, Northeast Agricultural University, Harbin, China
- Jiguo Gao,
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