已报道的虫媒病毒病原通常通过雌虫经卵垂直传播至子代昆虫，前期发现水稻瘤矮病毒(RGDV)经介体电光叶蝉以雄虫交配为主雌虫经卵为辅的方式传至子代，这种奇特的垂直传播方式可能是由RGDV外壳蛋白与精子表面受体硫酸乙酰肝素糖蛋白(HSPG)互作介导的。推测由于RGDV更适合在雄虫中存在且经精子垂直传播的效率较高，导致RGDV在我国南方省份长达30余年的常态流行。本项目将深入解析RGDV经雌虫经卵传播过程中受到各种屏障限制的机制，揭示RGDV外壳蛋白与精子HSPG识别介导病毒以雄虫交配高效传至子代的机制；通过比较带毒雌雄虫交配竞争力、生长发育及其持续传至后代等能力差异，探讨RGDV进化为以雄虫交配为主的垂直传播方式的内在机制；阐明自然条件下这种奇特病毒垂直传播方式与田间病毒病害常态流行之间的关系。研究结果将推动虫媒病毒相关领域发展，为探索通过抑制病毒与精子识别来对虫媒病毒进行绿色防控提供理论基础。

The reported vector-transmitted viral pathogens are generally transovarially transmitted by female insects into their offspring. We found that the vertical transmission of Rice gall dwarf virus (RGDV) by leafhopper vectors Recilia dorsalis adults into their offspring is dominantly mediated by male mating, with a low frequency of transovarial transmission by female adults. Such unique vertical transmission pathway is possibly mediated by the interaction of outer capsid protein of RGDV with the surface receptor of the sperm, heparin sulfate proteoglycan (HSPG). It is supposed that the preference of RGDV for maintaining in male insect, as well as the high efficiency of sperm-mediated vertical transmission, cause normal epidemic pattern of RGDV throughout Southern Provinces of China for more than 30 years. This proposal will further analyze the mechanisms how RGDV is encountered by various membrane or tissue barriers during the process of viral invasion into the ovary oocyte in female insects, and reveal the mechanisms how the specific interaction of coat protein of RGDV with HSPG of sperm mediates the vertical transmission of viruses into offspring by male mating with high efficiency. We will also compare the differences of mating competitiveness, development and passage ability to offspring between viruliferous male and female adults, discussing the intrinsic mechanism for RGDV to evolve the male mating-mediated vertical transmission. We hope to uncover the association of this unique vertical transmission of viruses with normal epidemic of viral diseases in the field. The results will promote the development of the study field of vector-transmitted viral pathogens, and provide the theoretical base for green control exploration of the viruses by inhibiting the recognition of virus and the sperm of male insect.