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Nagi SC, Lucas ER, Egyir-Yawson A, Essandoh J, Dadzie S, Chabi J, Djogbénou LS, Medjigbodo AA, Edi CV, Ketoh GK, Koudou BG, Ashraf F, Clarkson CS, Miles A, Weetman D, Donnelly MJ. Parallel Evolution in Mosquito Vectors-A Duplicated Esterase Locus is Associated With Resistance to Pirimiphos-methyl in Anopheles gambiae. Mol Biol Evol 2024; 41:msae140. [PMID: 38985692 PMCID: PMC11267716 DOI: 10.1093/molbev/msae140] [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: 02/14/2024] [Revised: 05/02/2024] [Accepted: 05/29/2024] [Indexed: 07/12/2024] Open
Abstract
The primary control methods for the African malaria mosquito, Anopheles gambiae, are based on insecticidal interventions. Emerging resistance to these compounds is therefore of major concern to malaria control programs. The organophosphate (OP), pirimiphos-methyl, is a relatively new chemical in the vector control armory but is now widely used in indoor-residual spray campaigns. While generally effective, phenotypic resistance has developed in some areas in malaria vectors. Here, we used a population genomic approach to identify novel mechanisms of resistance to pirimiphos-methyl in A. gambiae s.l mosquitoes. In multiple populations, we found large and repeated signals of selection at a locus containing a cluster of detoxification enzymes, some of whose orthologs are known to confer resistance to OPs in Culex pipiens. Close examination revealed a pair of alpha-esterases, Coeae1f and Coeae2f, and a complex and diverse pattern of haplotypes under selection in A. gambiae, A. coluzzii and A. arabiensis. As in C. pipiens, copy number variants have arisen at this locus. We used diplotype clustering to examine whether these signals arise from parallel evolution or adaptive introgression. Using whole-genome sequenced phenotyped samples, we found that in West Africa, a copy number variant in A. gambiae is associated with resistance to pirimiphos-methyl. Overall, we demonstrate a striking example of contemporary parallel evolution which has important implications for malaria control programs.
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Affiliation(s)
- Sanjay C Nagi
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Eric R Lucas
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | | | - John Essandoh
- Department of Biomedical Sciences, University of Cape Coast, Cape Coast, Ghana
| | - Samuel Dadzie
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Joseph Chabi
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Luc S Djogbénou
- Laboratory of Infectious Vector Borne Diseases, Tropical Infectious Diseases Research Center (TIDRC), Université d’Abomey-Calavi (UAC), 01 B.P. 526 Cotonou, Benin
| | - Adandé A Medjigbodo
- Laboratory of Infectious Vector Borne Diseases, Tropical Infectious Diseases Research Center (TIDRC), Université d’Abomey-Calavi (UAC), 01 B.P. 526 Cotonou, Benin
| | - Constant V Edi
- Research and Development Department, Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, 01 BP 1303 Abidjan, Côte d’Ivoire
| | - Guillaume K Ketoh
- Department of Zoology, Faculty of Sciences, Laboratory of Ecology and Ecotoxicology, Université de Lomé, 01 B.P. 1515 Lomé, Togo
| | - Benjamin G Koudou
- Research and Development Department, Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, 01 BP 1303 Abidjan, Côte d’Ivoire
| | - Faisal Ashraf
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Chris S Clarkson
- Wellcome Sanger Genomic Surveillance Unit, Wellcome Sanger Institute, Hinxton, Cambridge, CB10 1RQ, UK
| | - Alistair Miles
- Wellcome Sanger Genomic Surveillance Unit, Wellcome Sanger Institute, Hinxton, Cambridge, CB10 1RQ, UK
| | - David Weetman
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Martin J Donnelly
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
- Wellcome Sanger Genomic Surveillance Unit, Wellcome Sanger Institute, Hinxton, Cambridge, CB10 1RQ, UK
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Nagi SC, Lucas ER, Egyir-Yawson A, Essandoh J, Dadzie S, Chabi J, Djogbénou LS, Medjigbodo AA, Edi CV, Ketoh GK, Koudou BG, Ashraf F, Clarkson CS, Miles A, Weetman D, Donnelly MJ. Parallel evolution in mosquito vectors - a duplicated esterase locus is associated with resistance to pirimiphos-methyl in An. gambiae. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.01.578361. [PMID: 38352547 PMCID: PMC10862845 DOI: 10.1101/2024.02.01.578361] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
The primary control methods for the African malaria mosquito, Anopheles gambiae, are based on insecticidal interventions. Emerging resistance to these compounds is therefore of major concern to malaria control programmes. The organophosphate, pirimiphos-methyl, is a relatively new chemical in the vector control armoury but is now widely used in indoor residual spray campaigns. Whilst generally effective, phenotypic resistance has developed in some areas in malaria vectors. Here, we used a population genomic approach to identify novel mechanisms of resistance to pirimiphos-methyl in Anopheles gambiae s.l mosquitoes. In multiple populations, we found large and repeated signals of selection at a locus containing a cluster of detoxification enzymes, some of whose orthologs are known to confer resistance to organophosphates in Culex pipiens. Close examination revealed a pair of alpha-esterases, Coeae1f and Coeae2f, and a complex and diverse pattern of haplotypes under selection in An. gambiae, An. coluzzii and An. arabiensis. As in Cx. pipiens, copy number variation seems to play a role in the evolution of insecticide resistance at this locus. We used diplotype clustering to examine whether these signals arise from parallel evolution or adaptive introgression. Using whole-genome sequenced phenotyped samples, we found that in West Africa, a copy number variant in Anopheles gambiae is associated with resistance to pirimiphos-methyl. Overall, we demonstrate a striking example of contemporary parallel evolution which has important implications for malaria control programmes.
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Affiliation(s)
- Sanjay C. Nagi
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Eric R. Lucas
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | | | - John Essandoh
- Department of Biomedical Sciences, University of Cape Coast, Cape Coast, Ghana
| | - Samuel Dadzie
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Joseph Chabi
- Department of Parasitology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Luc S. Djogbénou
- Tropical Infectious Diseases Research Center (TIDRC), Université d’Abomey-Calavi (UAC), 01 B.P. 526 Cotonou, Benin
| | - Adandé A. Medjigbodo
- Tropical Infectious Diseases Research Center (TIDRC), Université d’Abomey-Calavi (UAC), 01 B.P. 526 Cotonou, Benin
| | - Constant V. Edi
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, 01 BP 1303 Abidjan, Côte d’Ivoire
| | - Guillaume K. Ketoh
- Laboratory of Ecology and Ecotoxicology, Department of Zoology, Faculty of Sciences, Université de Lomé, 01 B.P. 1515 Lomé, Togo
| | - Benjamin G. Koudou
- Centre Suisse de Recherches Scientifiques en Côte d’Ivoire, 01 BP 1303 Abidjan, Côte d’Ivoire
| | - Faisal Ashraf
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Chris S. Clarkson
- Wellcome Sanger Genomic Surveillance Unit, Wellcome Sanger Institute, Hinxton, Cambridge, CB10 1RQ, UK
| | - Alistair Miles
- Wellcome Sanger Genomic Surveillance Unit, Wellcome Sanger Institute, Hinxton, Cambridge, CB10 1RQ, UK
| | - David Weetman
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Martin J. Donnelly
- Department of Vector Biology, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
- Wellcome Sanger Genomic Surveillance Unit, Wellcome Sanger Institute, Hinxton, Cambridge, CB10 1RQ, UK
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Njoroge H, van't Hof A, Oruni A, Pipini D, Nagi S, Lynd A, Lucas ER, Tomlinson S, Grau‐Bove X, McDermott D, Wat'senga FT, Manzambi EZ, Agossa FR, Mokuba A, Irish S, Kabula B, Mbogo C, Bargul J, Paine MJI, Weetman D, Donnelly MJ. Identification of a rapidly-spreading triple mutant for high-level metabolic insecticide resistance in Anopheles gambiae provides a real-time molecular diagnostic for antimalarial intervention deployment. Mol Ecol 2022; 31:4307-4318. [PMID: 35775282 PMCID: PMC9424592 DOI: 10.1111/mec.16591] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 06/07/2022] [Accepted: 06/27/2022] [Indexed: 12/01/2022]
Abstract
Studies of insecticide resistance provide insights into the capacity of populations to show rapid evolutionary responses to contemporary selection. Malaria control remains heavily dependent on pyrethroid insecticides, primarily in long lasting insecticidal nets (LLINs). Resistance in the major malaria vectors has increased in concert with the expansion of LLIN distributions. Identifying genetic mechanisms underlying high-level resistance is crucial for the development and deployment of resistance-breaking tools. Using the Anopheles gambiae 1000 genomes (Ag1000g) data we identified a very recent selective sweep in mosquitoes from Uganda which localized to a cluster of cytochrome P450 genes. Further interrogation revealed a haplotype involving a trio of mutations, a nonsynonymous point mutation in Cyp6p4 (I236M), an upstream insertion of a partial Zanzibar-like transposable element (TE) and a duplication of the Cyp6aa1 gene. The mutations appear to have originated recently in An. gambiae from the Kenya-Uganda border, with stepwise replacement of the double-mutant (Zanzibar-like TE and Cyp6p4-236 M) with the triple-mutant haplotype (including Cyp6aa1 duplication), which has spread into the Democratic Republic of Congo and Tanzania. The triple-mutant haplotype is strongly associated with increased expression of genes able to metabolize pyrethroids and is strongly predictive of resistance to pyrethroids most notably deltamethrin. Importantly, there was increased mortality in mosquitoes carrying the triple-mutation when exposed to nets cotreated with the synergist piperonyl butoxide (PBO). Frequencies of the triple-mutant haplotype remain spatially variable within countries, suggesting an effective marker system to guide deployment decisions for limited supplies of PBO-pyrethroid cotreated LLINs across African countries.
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Affiliation(s)
- Harun Njoroge
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
- Kenya Medical Research Institute (KEMRI) Centre for Geographic Medicine CoastKEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
| | - Arjen van't Hof
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
| | - Ambrose Oruni
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
- College of Veterinary MedicineAnimal Resources and Bio‐securityMakerere UniversityKampalaUganda
| | - Dimitra Pipini
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
| | - Sanjay C. Nagi
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
| | - Amy Lynd
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
| | - Eric R. Lucas
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
| | - Sean Tomlinson
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
| | - Xavi Grau‐Bove
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
| | - Daniel McDermott
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
| | | | - Emile Z. Manzambi
- Institut National de Recherche BiomédicaleKinshasaDemocratic Republic of Congo
| | - Fiacre R. Agossa
- USAID President's Malaria Initiative, VectorLink Project, Abt AssociatesRockvilleMarylandUSA
| | - Arlette Mokuba
- USAID President's Malaria Initiative, VectorLink Project, Abt AssociatesRockvilleMarylandUSA
| | - Seth Irish
- U.S. President's Malaria Initiative and Centers for Disease Control and PreventionAtlantaGeorgiaUSA
| | - Bilali Kabula
- Amani Research CentreNational Institute for Medical ResearchTanzania
| | - Charles Mbogo
- Population Health UnitKEMRI‐Wellcome Trust Research ProgrammeNairobiKenya
- KEMRI‐Centre for Geographic Medicine Research CoastKilifiKenya
| | - Joel Bargul
- Department of BiochemistryJomo Kenyatta University of Agriculture and TechnologyJujaKenya
- The Animal Health DepartmentInternational Centre of Insect Physiology and EcologyNairobiKenya
| | - Mark J. I. Paine
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
| | - David Weetman
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
| | - Martin J. Donnelly
- Department of Vector BiologyLiverpool School of Tropical MedicineLiverpoolUK
- Parasites and Microbes ProgrammeWellcome Sanger InstituteCambridgeUK
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Lin Z, Pang S, Zhang W, Mishra S, Bhatt P, Chen S. Degradation of Acephate and Its Intermediate Methamidophos: Mechanisms and Biochemical Pathways. Front Microbiol 2020; 11:2045. [PMID: 33013750 PMCID: PMC7461891 DOI: 10.3389/fmicb.2020.02045] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 08/03/2020] [Indexed: 11/28/2022] Open
Abstract
Acephate is an organophosphate pesticide that has been widely used to control insect pests in agricultural fields for decades. However, its use has been partially restricted in many countries due to its toxic intermediate product methamidophos. Long term exposure to acephate and methamidophos in non-target organisms results in severe poisonous effects, which has raised public concern and demand for the removal of these pollutants from the environment. In this paper, the toxicological effects of acephate and/or methamidophos on aquatic and land animals, including humans are reviewed, as these effects promote the necessity of removing acephate from the environment. Physicochemical degradation mechanisms of acephate and/or methamidophos are explored and explained, such as photo-Fenton, ultraviolet/titanium dioxide (UV/TiO2) photocatalysis, and ultrasonic ozonation. Compared with physicochemical methods, the microbial degradation of acephate and methamidophos is emerging as an eco-friendly method that can be used for large-scale treatment. In recent years, microorganisms capable of degrading methamidophos or acephate have been isolated, including Hyphomicrobium sp., Penicillium oxalicum, Luteibacter jiangsuensis, Pseudomonas aeruginosa, and Bacillus subtilis. Enzymes related to acephate and/or methamidophos biodegradation include phosphotriesterase, paraoxonase 1, and carboxylesterase. Furthermore, several genes encoding organophosphorus degrading enzymes have been identified, such as opd, mpd, and ophc2. However, few reviews have focused on the biochemical pathways and molecular mechanisms of acephate and methamidophos. In this review, the mechanisms and degradation pathways of acephate and methamidophos are summarized in order to provide a new way of thinking for the study of the degradation of acephate and methamidophos.
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Affiliation(s)
- Ziqiu Lin
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Shimei Pang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Wenping Zhang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Sandhya Mishra
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Pankaj Bhatt
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
| | - Shaohua Chen
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China
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Martins WFS, Subramaniam K, Steen K, Mawejje H, Liloglou T, Donnelly MJ, Wilding CS. Detection and quantitation of copy number variation in the voltage-gated sodium channel gene of the mosquito Culex quinquefasciatus. Sci Rep 2017; 7:5821. [PMID: 28725028 PMCID: PMC5517494 DOI: 10.1038/s41598-017-06080-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 06/07/2017] [Indexed: 01/23/2023] Open
Abstract
Insecticide resistance is typically associated with alterations to the insecticidal target-site or with gene expression variation at loci involved in insecticide detoxification. In some species copy number variation (CNV) of target site loci (e.g. the Ace-1 target site of carbamate insecticides) or detoxification genes has been implicated in the resistance phenotype. We show that field-collected Ugandan Culex quinquefasciatus display CNV for the voltage-gated sodium channel gene (Vgsc), target-site of pyrethroid and organochlorine insecticides. In order to develop field-applicable diagnostics for Vgsc CN, and as a prelude to investigating the possible association of CN with insecticide resistance, three assays were compared for their accuracy in CN estimation in this species. The gold standard method is droplet digital PCR (ddPCR), however, the hardware is prohibitively expensive for widespread utility. Here, ddPCR was compared to quantitative PCR (qPCR) and pyrosequencing. Across all platforms, CNV was detected in ≈10% of mosquitoes, corresponding to three or four copies (per diploid genome). ddPCR and qPCR-Std-curve yielded similar predictions for Vgsc CN, indicating that the qPCR protocol developed here can be applied as a diagnostic assay, facilitating monitoring of Vgsc CN in wild populations and the elucidation of association between the Vgsc CN and insecticide resistance.
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Affiliation(s)
- Walter Fabricio Silva Martins
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
- Departamento de Biologia, Universidade Estadual da Paraíba, Campina Grande, Brazil
| | | | - Keith Steen
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Henry Mawejje
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | - Triantafillos Liloglou
- Department of Molecular and Clinical Cancer Medicine, Roy Castle Lung Cancer Research, Liverpool, UK
| | - Martin James Donnelly
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool, UK
- Malaria Programme, Wellcome Trust Sanger Institute, Cambridge, UK
| | - Craig Stephen Wilding
- School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, UK.
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Chénais B, Caruso A, Hiard S, Casse N. The impact of transposable elements on eukaryotic genomes: from genome size increase to genetic adaptation to stressful environments. Gene 2012; 509:7-15. [PMID: 22921893 DOI: 10.1016/j.gene.2012.07.042] [Citation(s) in RCA: 200] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Revised: 07/16/2012] [Accepted: 07/25/2012] [Indexed: 11/25/2022]
Abstract
Transposable elements (TEs) are present in roughly all genomes. These mobile DNA sequences are able to invade genomes and their impact on genome evolution is substantial. The mobility of TEs can induce the appearance of deleterious mutations, gene disruption and chromosome rearrangements, but transposition activity also has positive aspects and the mutational activities of TEs contribute to the genetic diversity of organisms. This short review aims to give a brief overview of the impact TEs may have on animal and plant genome structure and expression, and the relationship between TEs and the stress response of organisms, including insecticide resistance.
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Affiliation(s)
- Benoît Chénais
- Université du Maine, EA2160 Mer Molécules Santé, UFR Sciences et Techniques, Avenue Olivier Messiaen, F-72085 Le Mans, France.
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Cui F, Weill M, Berthomieu A, Raymond M, Qiao CL. Characterization of novel esterases in insecticide-resistant mosquitoes. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2007; 37:1131-1137. [PMID: 17916499 DOI: 10.1016/j.ibmb.2007.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2007] [Revised: 06/28/2007] [Accepted: 07/02/2007] [Indexed: 05/25/2023]
Abstract
In the mosquito Culex pipiens complex (Diptera: Culicidae), the amplification of carboxylesterase genes is an important mechanism providing resistance to organophosphate insecticides. Various amplified alleles at the Ester locus have been identified over the world. In this study, two newly detected Ester alleles, Ester(B10) and Ester(11) (including associated Ester(A11) and Ester(B11)), coding for esterases B10 and A11-B11, respectively, are characterized qualitatively and quantitatively. A high molecular identity is observed both at the nucleotide level and at the deduced amino acid level among the known Ester alleles. Real-time quantitative PCR results suggest 2.5-fold amplification of the Ester(B10) allele, 36.5-fold amplification of the Ester(A11) allele, and 19.1-fold amplification of the Ester(B11) allele. The ca. 2-fold difference in amplification level between Ester(A11) and Ester(B11) may indicate a new model for the esterase amplification. Bioassays show that these two resistant Ester alleles only can confer moderate or low resistance to the tested organophosphate insecticides.
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Affiliation(s)
- Feng Cui
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080, China
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