章鱼胺响应交配介导cAMP-PKA信号通路调控褐飞虱生殖的机制研究

以前研究表明药剂诱导褐飞虱雄虫的生殖效应经交配使雌虫产生显著的交配后效应。但调控雌虫交配后效应的途径及其作用机理不清楚。申请者前期研究发现NlAC9基因表达与雌虫产卵有关，交配的雌虫卵巢内章鱼胺（OA）含量显著增加。基于昆虫OA生理功能及其信号传导的研究进展，我们提出了“OA响应交配介导cAMP/PKA信号通路调控褐飞虱生殖”的假设。本项目拟在前期研究基础上采用RNAi干扰、生物测定、Western blot和免疫荧光等方法，解析褐飞虱雌虫体内OA信号对交配的响应机理，探明OA及Octβ2R受体对雌虫生殖及行为的调控，明确CREB1在雌虫生殖和种群增长中的功能，最终揭示OA响应交配介导cAMP-PKA-CREB1信号通路调控褐飞虱雌虫生殖的作用机制。本研究将从新的角度揭示该害虫种群繁殖、暴发成灾的分子机制。

Previous studies have demonstrated that insecticide-induced male reproduction effects can be transferred into females during mating, following a significant post-mating effect that stimulates female egg-laying. However, the molecular mechanism underlying possible pathways that modulate female post-mating effect is not well understood. Our latest results showed that the expression of NlAC9 gene was be correlated with the fecundity of female adult, and octopamine (OA) content of ovary in mated females was significantly increased compared to unmated females. Associating our findings with the current knowledge on physiological functions and signal transduction cascade of OA, a hypothesis that OA response to mating mediates cAMP-PKA signaling pathway modulating the fecundity of N. lugens was posed. Based on previously accumulated achievements, this program aims to confirm this hypothesis from the following aspects. Firstly, we intends to explore the mating-responsive mechanisms of OA, illuminate regulatory roles played by juvenile hormone and OA as well as its Octβ2R receptor in female fecundity, and unravel the function by which CREB1 implicates in N. lugens female fecundity and population growth using RNAi interference, bioassay, western blot and immunofluorescence. By comprehensive analysis of results derived from this program, the functional mechanism of mating-responsive OA that mediates cAMP-PKA-CREB1 signaling pathway modulating the fecundity of N. lugens will be illustrated. This study will elucidate pivotal modulating pathways of the post-mating effects in Hemipteran females and reveal physiological ecology and molecular mechanisms of the pest population outbreak from new insights.