基于FKBP和钙调蛋白互作调控的烟粉虱对溴氰虫酰胺抗性的分子机制

To understand the resistance mechanisms are the one of the most important basis of insecticides resistance management. The resistance of pest insects to the diamide insecticides increased dramatically in recent years due to the extensive and intensive application. It has been proved that point mutations and upregulated expression of the ryanodine receptor (RyR) play essential role in the resistance to diamide insecticides. We have found that two kinds of regulatory protein of RyR, FK506 binding protein (FKBP) and calmodulin, may be involved in the resistance to diamide insecticide in whitefly, Bemisia tabaci. To understand the role of FKBP and calmodulin interaction in resistance to diamide insecticides, we will use toxicology, physiology and molecular biology methods to: 1) Clone and characterize the cDNA sequences of all FKBP and calmodulin family genes in B. tabaci; 2) Investigate the biological functions of FKBP and calmodulin family genes as well as their interactions; 3) Reveal the roles of FKBP and calmodulin family genes in cyantraniliprole resistance in B. tabaci by using the RNA interference technique. The expected results will reveal the role of the two RyR regulate proteins in diamide insecticides resistance and provide a theoretical basis for the resistance management in B. tabaci.

害虫抗药性机制研究是抗性治理的重要基础。双酰胺类杀虫剂近年来在田间广泛使用导致害虫抗性风险急剧上升，研究表明其作用靶标鱼尼丁受体基因的突变和表达上调与害虫对双酰胺类杀虫剂高水平抗性密切相关。申请者前期研究发现，鱼尼丁受体调控蛋白FKBP和钙调蛋白可能参与烟粉虱对溴氰虫酰胺的抗性。为明确这两种蛋白互作调控在烟粉虱对溴氰虫酰胺抗性中的分子机制，拟利用毒理学、生理学和分子生物学的手段：1）克隆烟粉虱鱼尼丁受体调控蛋白FKBP和钙调蛋白家族不同基因的cDNA序列全长，并系统分析其分子特性；2）研究FKBP和钙调蛋白的生物学功能及其互作关系；3）通过RNAi技术研究FKBP和钙调蛋白在烟粉虱对溴氰虫酰胺抗性发展中的作用。研究结果将阐明鱼尼丁受体调控蛋白在溴氰虫酰胺抗性中的作用，揭示烟粉虱对双酰胺类杀虫剂的抗性机制，为害虫抗性治理提供理论依据。

溴氰虫酰胺是重大农业害虫烟粉虱抗性治理过程中一个重要的替代药剂，然而烟粉虱的抗性监测显示部分田间种群已经对溴氰虫酰胺产生中等水平的抗性。为明确钙离子结合蛋白介导的烟粉虱对溴氰虫酰胺的抗性机制，本项目利用毒理学、生理学、分子生物学和细胞生物学的手段：1）克隆鉴定出钙离子结合蛋白1、2（CaBP1和CaBP2）、钙调素（Calmodulin）及FK结合蛋白（FKBP）四个烟粉虱RyR调控蛋白的全长基因序列，并分析其序列特性；2）明确了上述四个调控蛋白在烟粉虱不同发育历期的表达谱以及其对烟粉虱生长发育的影响；3）利用RNAi技术明确了四个调控蛋白在烟粉虱对溴氰虫酰胺抗性中的作用；4）利用真核细胞异源表达及钙离子成像技术揭示了上调表达三个调控蛋白（CaBP1，CaBP2和CaM）能够抑制溴氰虫酰胺引起的钙离子释放速度和强度。该研究成果对于全面理解烟粉虱对溴氰虫酰胺的抗性机制，指导田间烟粉虱的抗药性治理具有重要的理论意义。