水稻矮缩病毒（RDV）引致的普通矮缩病对我国水稻造成过严重的损害。RDV主要由两点黑尾叶蝉以持久的方式进行传播。病毒能够在叶蝉和植物中复制，经卵传播但不对其造成病害。siRNA介导的RNA沉默是多种真核生物用于防御病毒侵染的方策略之一,在模式植物拟南芥和模式动物中研究较多。但是，在重要禾本科作物如水稻和传播病毒介体昆虫中缺乏研究。以RDV为代表的多种植物双链RNA病毒是引起重要作物严重病害的病毒。这项课题以叶蝉传播的水稻矮缩病毒，叶蝉和水稻为系统，应用细胞生物学、基因组学、分子生物学和免疫学等多种手段，研究siRNA 的产生机制，siRNA介导的RNA沉默在介体叶蝉和宿主水稻对RDV侵染中的防御机制及RNA沉默通路中重要细胞因子的作用机制和调控。研究结果将为探明昆虫传播病毒机制和宿主水稻抵御病毒提供分子基础，并为进一步通过控制昆虫传毒以及提高宿主水稻的防御能力来控制病毒病提供依据。

Insect vector-transmitted viral diseases are the most severe rice diseases that cause heavy yield losses in rice production. Rice dwarf virus (RDV), the pathogen of rice common dwarf disease, is transmitted in nature by leafhopper in a propagative manner, multiplies in the insect cells, retains infectivity throughout the insect’s life span, but does not cause disease in the insect. In this project, we will use RDV, leafhopper and rice as a model system to address the mechanisms of siRNA-mediated antiviral RNA silencing in the insect vector and in rice. It has the following aspects: small RNA biogenesis in both hosts; RNA silencing mechanism in antiviral infection in insect and rice; effects of viral infection on host gene transcription, especially the genes involved in the RNA silencing pathway; and expression regulation of RNA silencing components. Results from this project will generate new and important molecular insights into mechanisms of viral transmission by an insect vector and antiviral mechanisms in leafhopper and rice. Furthermore, such insights may form a foundation for developing novel technologies to control viral diseases.