Deltamethrin interacts with Culex quinquefasciatus odorant-binding protein: a novel potential resistance mechanism

Parasites & Vectors

Yan Chen¹  Jia-hong Wu¹  Dan Xing²  Chun-xiao Li²  Tong-yan Zhao²  Heng-duan Zhang²  Ning Zhang²  Yi-ting Wang²  Rui-xin Shen³ 

[1] Guizhou Medical University, 550000, Guiyang, China;State Key Laboratory of Pathogen and Biosecurity, Beijing Key Laboratory of Vector Borne and Natural Focus Infectious Disease, Beijing Institute of Microbiology and Epidemiology, 100071, Beijing, China;State Key Laboratory of Pathogen and Biosecurity, Beijing Key Laboratory of Vector Borne and Natural Focus Infectious Disease, Beijing Institute of Microbiology and Epidemiology, 100071, Beijing, China;Guizhou Medical University, 550000, Guiyang, China;

关键词: Culex quinquefasciatus;    Deltamethrin;    Resistance;    Odorant-binding protein 28;    RNA interference;   

DOI  :  10.1186/s13071-021-05041-5

来源: Springer

【 摘 要 】

BackgroundOdorant-binding proteins (OBPs) play important roles in many physiological processes of mosquitoes. Previous high-throughput sequencing studies have revealed that some OBPs of Culex quinquefasciatus might be involved in the development of resistance to insecticides.MethodsBased on the results of sequencing analyses, the OBP28 gene was selected for evaluation in this study. Three laboratory strains of Cx. quinquefasciatus [susceptible strain (SS), deltamethrin-resistant strain 1 (HN) and deltamethrin-resistant strain 2 (RR)] were first examined by using the Centers for Disease Control and Prevention bottle bioassay, after which the expression level of the OBP28 gene in the susceptible and deltamethrin-resistant strains was determined by real-time quantitative polymerase chain reaction. The OBP28 gene in deltamethrin-resistant strain RR was silenced using RNA interference technology. The expression level of OBP28 and the resistance level were tested in the silenced strain and control strain after microinjection of double-stranded RNA for a 48-h interference period. Four field-collected strains (henceforth ‘field strains’) of Cx. quinquefasciatus were also examined for their resistance to deltamethrin and levels of OBP28 expression. Finally, a correlation analysis between deltamethrin resistance and gene expression was carried out for all seven strains, i.e. the four field strains and the three laboratory strains.ResultsIn the bioassay, the mortality of SS, HN and RR was 100%, 21.33% and 1.67%, respectively. The relative expression levels of OBP28 in strains HN and RR were 6.30- and 6.86-fold higher, respectively, than that of strain SS. After silencing of the OBP28 gene, the mortality of strain RR was 72.20% and that of the control strain 26.32%. The mortality of strain RR increased significantly after interference compared to that of the control strain. There was a negative correlation between OBP28 gene expression and mortality in adult mosquitoes after exposure to deltamethrin.ConclusionsTo our knowledge, this study shows for the first time a correlation between the expression of a gene coding for OBP and insecticide resistance in mosquitoes. The potential resistance mechanism that was elucidated provides a new target gene for the surveillance of resistance in mosquitoes.Graphical abstract

【 授权许可】

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