小菜蛾和甜菜夜蛾感受异硫氰酸酯类气味受体基因的功能鉴定及比较分析

芥子油苷及其水解产物是十字花科植物的标志性次生物质，其中的挥发性异硫氰酸酯类水解产物（ITC）是吸引专食性蛾类雌虫产卵的特征气味，解析昆虫对ITC特异感受的嗅觉受体（OR）基因及其功能并进行昆虫间比较分析，对于揭示昆虫-植物间的协同进化及昆虫食性的分化机制均具重要意义，但相关研究仍属空白。项目拟以十字花科植物专食性小菜蛾及非专食性甜菜夜蛾为对象，首先测定明确引诱两种害虫产卵的ITC关键组分；然后通过触角转录组、性别差异表达等分析，获得候选OR基因；再后利用蛙卵系统结合双极电压钳技术进行体外功能分析，确定OR基因；最后采用CRISPR/Cas9技术结合电生理及行为测定技术，明确两种昆虫中感受ITC类气味的OR基因及功能，分析不同食性昆虫间的差异；同时测定不同结构ITC及其类似物的活性，探讨构效关系。研究成果将深化对十字花科植物-昆虫协同进化机制的认识，并为害虫高效行为调控技术的开发提供指导。

Glucosinolates and their breakdown products are the secondary metabolites characterized by the Crucifer plants. Among those breakdown products, volatile isothiocyanates (ITC) are the specific signals attracting females for oviposition in Crucifer specialist insects. To identify the olfactory receptor (OR) genes and characterize the function are very important for better understanding of the plant-insects coevolution and insect feeding differentiation, but there is no related study reported yet. The present project is aimed to characterize the ORs for ITC in two moths, a crucifer specialist (Plutella xylostella) and a crucifer generalist (Spodoptera exigua). Firstly, key ITC volatiles attracting female moths will be determined by bioassays; then candidate OR genes for ITC will be screened out by analyses of female antenna transcriptome data followed by female biased expression; thirdly, ORs will be functional analyzed using heterologous expression system Xenopus oocytes coupled with electrophysiological technique; fourthly, the OR genes will be in vivo functionally determined, using the newly developed CRISPR/Cas9 genome editing technique together with the electrophysiological and behavioral assays. At meantime, the relationship between the structure and activity for the ITC will be explored by measuring the activity of ITC with different structure. The results will be helpful for deeper understanding the plant-insect coevolution, and at meantime provide potential target for new pest control technique, and provide guidance for screening of the active volatiles used for pest control.