棉铃虫和烟青虫是重要的农业害虫，也是少有的几种能取食辣椒果实的昆虫。辣椒素是辣椒属植物中独特的次生物质，在防御食果动物和真菌侵害中发挥着重要作用。棉铃虫和烟青虫通过什么机制来适应毒性辣椒素至今尚不清楚。本项目拟从辣椒素代谢解毒角度，以CYP6B6-辣椒素为研究模型，在CYP6B6对辣椒素代谢活性和辣椒素对CYP6B6的转录表达调控两个相互关联的方面，平行对比分析两亲缘关系很近但寄主范围不同的铃夜蛾属姊妹种害虫对辣椒素适应性的分子机制，探讨细胞色素P450直系同源基因可能存在的功能分化及其表达调控方式的分歧。预期研究结果在理论上将有助于在分子水平上认识昆虫应对有毒化合物胁迫的进化策略、揭示广食性与专食性昆虫P450直系同源基因的进化命运；在实践上，可为通过调控解毒酶系活性、充分利用植物中的抗虫物质防治害虫提供思路，促进辣椒素在害虫防治中的科学应用，指导以辣椒素为先导化合物的新农药创制。

Both Helicoverpa armigera and H. assulta are important agricultural pests. They are also the few insects that can survive on Capsicum fruits. Capsaicin is the principal secondary compound in pepper plants, and can function as one of the defense mechanisms against frugivore animals and fungi. Until now, the molecular mechanism underlying the adaptation to toxic capsaicin by H. armigera and H. assulta remains largely unknown. The objectives of this project are to determine how CYP6B6 metabolizes capsaicin and how capsaicin regulates transcriptional expression of CYP6B6 gene. The gene sequence, expression pattern, metabolic capacity towards capsaicin and transcriptional responses to capsaicin stress of the CYP6B6 orthologues in the two closely related Helicoverpa species with different hostplant breadth will be parallel studied. The anticipated results obtained from this project will not only enhance our understanding on how insects cope with toxic compounds in their diets and the evolutionary fate of cytochrome P450 orthologues in an ecological and evolutionary context, but also promote the development of detoxification-interfering strategies for pepper pest control and the discovery of capsaicin-based pesticides.