CYP6家族基因介导烟粉虱对溴氰虫酰胺抗性的分子机制

Bemisia tabaci is one of the most important agricultural pests in the world, which seriously threatens the safety of agriculture. Cyantraniliprole, the second-generation O-aminobenediamide insecticide, has been widely used to control a serious worldwide agricultural pests Bemisia tabaci. However, field Bemisia tabaci populations have developed resistance to cyantraniliprole, and there is still lack of research on factors that the resistance and regulation mechanism of Bemisia tabaci to cyantraniliprole. Base on this scientific issue , previous studies of the near-isogenic resistant strain generation, biochemical synergy experiment, comparative transcriptional analysis and gene expression spectrum analysis, we found three over-expressed cytochrome P450 genes CYP6DP6, CYP6DW3, CYP6DB3 maybe play a very important role in cyantraniliprole resisance. In this study intends to use the methods of dual-luciferase reporter gene system, functional expression and RNAi to study the transcription factor regulation mechanism of CYP6DP6, CYP6DW3, CYP6DB3 in Bemisia tabaci. Our expected results will reveal the regulation mechanism of cyantraniliprole resistance, and provide a basis for research on the regulation of excessive expression of CYP6 genes in the mechanism of cyantraniliprole resistance in Bemisia tabaci, and provide a theoretical significance to further establish the IPM strategies for whiteflies.

烟粉虱作为世界性重要农业害虫，严重威胁着农业的安全生产。目前，新型杀虫剂溴氰虫酰胺广泛用于防治烟粉虱且效果显著。经过前期开展抗性监测工作，我们发现烟粉虱田间种群对溴氰虫酰胺存在不同水平抗性，但抗性相关机制鲜有报道。随后，本课题组建立了烟粉虱溴氰虫酰胺抗性近等基因系，通过前期生化增效实验、比较转录组学分析以及基因表达谱分析，发现CYP6DP6、CYP6DW3、CYP6DB3的过量表达可能参与了烟粉虱对溴氰虫酰胺抗性产生。本研究在此基础上拟采用RNA干扰、细胞表达及双荧光素酶报告基因检测等技术手段，深入明确上述3个CYP6基因在抗性的作用及其相关分子调控机制。预期研究结果将揭示CYP6基因介导烟粉虱对溴氰虫酰胺抗性机制，为今后深入开展烟粉虱对溴氰虫酰胺抗性机理中CYP6基因过量表达的级联调控提供理论基础，也为制订烟粉虱的抗性治理策略提供理论依据。

害虫对杀虫剂产生抗药性可导致防治失败进而引起经济损失，研究抗药性的形成机理可作为害虫综合治理的理论基础。第二代邻氨基苯甲二酰胺类杀虫剂溴氰虫酰胺广泛用于防治世界性农业害虫烟粉虱，在前期工作中，我们发现烟粉虱田间种群对其有中等水平抗性，但抗性形成机制却并不明确。针对这一科学问题，本课题组建立了烟粉虱溴氰虫酰胺抗性近等基因系，通过增效剂实验及RNA-seq分析，证实四个CYP6家族基因过量表达在抗性形成过程中发挥重要作用。通过定量PCR，测定其表达水平，表达特征，探讨其代谢抗性的机制。上述结果可用于研究溴氰虫酰胺抗性的机制，对于烟粉虱的防治具有重要意义，为今后深入开展烟粉虱对溴氰虫酰胺等外源物质的信号响应途径研究提供理论基础，也为制定烟粉虱的综合治理对策提供理论依据。