褐飞虱类酵母共生菌经卵垂直传播过程中分子调控机制的研究

Yeast-like symbiont (YLS) is necessary for brown planthopper (BPH, Nilaparvata lugens Stål) to maintain normal growth and development, and assists BPH in adapting resistant rice varieties and withstanding pesticides. YLS is transmitted transovarially between BPH generations, and thus works consistently in BPH population reproduction. However, the underlying molecular regulation mechanism of transovarial transmission of YLS in BPH is unclear, which limits studies on the way to control BPH from YLS perspective. In this project, we will use RNA-Seq technology to compare gene expression profiles of BPH ovaries during YLS transovarial transmission, and screen differentially expressed genes involved in the endocytosis, vitellogenin accumulation and expression regulation of cytoskeletal proteins signal pathways. Based on qPCR, immunofluorescence and RNAi technologies, the functions of these genes and their roles in regulating the transovarial transmission of YLS in BPH will be elucidated. Finally, we will clarify the key genes regulating the transovarial transmission of YLS, and explore its molecular regulation mechanism, providing theoretical basis for the control method of making BPH offsprings hard to keep alive through controlling YLS vertical transmission in BPH. Meanwhile, this project will establish a model in the research field of transovarial transmission regulation mechanism of insect fungal endosymbionts, and benefit research works on the vertical transmission of other insect fungal endosymbionts.

类酵母共生菌（YLS）是褐飞虱正常生长发育所必需，能协同褐飞虱适应抗性水稻品种和抵抗杀虫剂。YLS在褐飞虱代次间能经卵垂直传播，从而持续地在褐飞虱种群繁殖中发挥作用。然而，YLS经卵垂直传播的分子调控机制却不清楚，限制了从YLS角度开展褐飞虱防治工作的研究。为此，本项目将通过RNA-Seq技术比较YLS经卵垂直传播过程中褐飞虱卵巢基因表达谱的变化，从细胞内吞、卵黄原蛋白沉积和细胞骨架蛋白表达调控等信号途径中筛选出差异表达基因；并借助定量PCR、免疫荧光、RNAi等技术研究相关基因在YLS经卵垂直传播中的作用，从而明确调控YLS经卵垂直传播的关键基因，阐明YLS经卵垂直传播的分子调控机制，为今后通过控制YLS垂直传播而使子代褐飞虱难以存活的防治方法提供理论基础。同时，本项目有望在昆虫内共生真菌垂直传播调控机制的研究领域构建一个研究模式，从而有利于其它昆虫内共生真菌垂直传播研究工作的开展。

类酵母共生菌（YLS）是褐飞虱正常生长发育所必需，能协同褐飞虱适应抗性水稻品种和抵抗杀虫剂。YLS在褐飞虱代次间能经卵垂直传播，从而持续地在褐飞虱种群繁殖中发挥作用。然而，YLS经卵垂直传播的分子调控机制却不清楚，限制了从YLS角度开展褐飞虱防治工作的研究。本项目通过RNA-Seq技术比较了YLS经卵垂直传播过程中褐飞虱卵巢和上皮栓基因表达谱的变化，从卵黄原蛋白沉积、细胞内吞和细胞骨架蛋白表达调控等信号途径中筛选出Vg、CHC、Dynamin和Endophilin等差异表达基因；并借助定量PCR、免疫荧光、RNAi等技术研究了这些基因在YLS经卵垂直传播中的作用。研究结果发现卵黄发生先于YLS进入卵巢，卵黄发生是YLS进入卵巢的驱动因子，CHC、Dynamin和Endophilin与褐飞虱卵巢发育关系密切，并在YLS经卵传播中起着重要作用，其中，CHC发挥着关键作用。这些结果是充分阐明YLS经卵垂直传播调控机制的研究过程中的重要一步，为今后通过控制YLS垂直传播而使子代褐飞虱难以存活的防治方法提供了理论基础。本项目中所研究的重要基因，可作为防治褐飞虱的新靶标。