Resistance of AMPKα gene mediated Aedes albopictus to dimefluthrin

【Objective】To explore the relationship between adenosine monophosphate activated protein kinase（AMPK） gene（AalAMPKα）and dimefluthrin resistance in Aedes albopictus，and to explore the mechanism of resistance formation to dimefluthrin in Aedes albopictus，which could provide scientific basis for comprehensive control of Aedes albopictus. 【Method】The sequence of coding region（CDS）of AalAMPKα was cloned，and bioinformatics analysis was carried out by online softwares such as Protparam，SMART，SWISS-MODEL and GSD_v2.0. Real-time fluorescence quantitative PCR was used to detect the expression of AalAMPKα in different tissues and developmental stages of Aedes albopictus. The resistance of Aedes albopictus to dimefluthrin was determined by the micro-drop method，the function of AalAMPKα gene in drug resistance of Aedes albopictus was investigated using RNA interference technology.【Result】The full length sequence of AalAMPKα was 1653 bp and encoded 545 amino acids，the molecular weight of the protein was 61.63 kD， and the theoretical isoelectric point（pI）was 8.03，which was a hydrophilic protein. Sequence analysis revealed that the amino acid sequence encoded by the AalAMPKα gene contained highly conserved domains shared with other species. The AalAMPKα gene encoded amino acid sequence showed the highest similarity with that of the AMPKα gene from Aedes aegypti and exhibited close phylogenetic relationships with other Dipteran insects. Genome structure analysis showed that the genome structure of AMPKα gene varied greatly among different species，showing species specificity. AalAMPKα gene was expressed to varying degrees in different tissues and at different developmental stages of Aedes albopictus，with the highest expression in fat body and one-day male mosquitoes. The expression of AalAMPKα gene in resistant Aedes albopictus was as 3.98 times as that of susceptible strain. The lethal medium dose（LD₅₀）of dimefluthrin to Aedes albopictus susceptible strain and resistant strain were 0.354 and 8.010 ng/insect respectively，and the resistance times was 22.63， indicating a high level of resistance. After 24 h microinjection of double-strand ribonucleic acid （dsRNA） silent AalAMPKα gene on resistant strain of Aedes albopictus，the LD₅₀ of dsGFP group was 7.876 ng/insect，and that of dsAalAMPKα group was 2.631 ng/insect. The resistance times decreased from 22.25 to 7.43 after silenced AalAMPKα gene， drug resistance was extremely significantly decreased（P<0.001）.【Conclusion】AalAMPKα gene mediates the resistance of Aedes albopictus to dimefluthrin.