马铃薯RanGAP蛋白在马铃薯Y病毒侵染过程中的作用机制

Potato virus Y (PVY) is one of the most destructive virus affecting potato production. Planting resistant cultivars is the most economic and efficient way to control potato viral diseases, however, most commercial potato cultivars are highly susceptible to PVY. Breeding new resistant potato cultivars becomes one of most urgent problems confronting potato production. Recently, the applicant has obtained a new HCpro interacting protein RanGAP using Co-IP. Over-expressing RanGAP reduced the accumulation level of PVY, while silencing Ran GAP enhanced the virulence of PVY. However, its mechanism during PVY infection remains unclear. In this proposal, we will screen and identify the RanGAP-interacting PVY and host proteins, study the signaling pathway regulated by RanGAP during PVY infection, characterize the effect of over-expressing or silencing RanGAP on the infection of other viruses infecting potato and dissect the role of RanGAP from other host during PVY infection. The expected results will elucidate the mechanisms of potato RanGAP protein involved in PVY infection, reveal new antiviral targets for the control of PVY and other related viruses.

马铃薯Y病毒（Potato virus Y，PVY）是危害马铃薯安全生产的重要病毒。种植抗病品种是防治马铃薯病毒病最根本有效的方法，但现有品种大都不抗PVY，因此培育抗PVY新品种是马铃薯生产中急需解决的问题。申请者在PVY HCpro复合体中筛选到RanGAP蛋白，超表达该蛋白能降低PVY在寄主中的积累水平，沉默该蛋白则提高PVY致病力，但其作用机制还不清楚。本项目拟鉴定与马铃薯RanGAP直接互作的病毒蛋白，明确RanGAP与PVY蛋白的互作网络；鉴定与马铃薯RanGAP互作的马铃薯蛋白，阐明RanGAP参与PVY侵染的信号通路；分析马铃薯RanGAP超表达或沉默对其它病毒侵染的影响、其它寄主RanGAP超表达或沉默对PVY侵染的影响。预期结果将阐明马铃薯RanGAP在PVY侵染过程中的作用机制，发现新的抗病毒靶标，为培育抗PVY马铃薯品种提供依据，也可为相关病毒的防治提供理论指导。

马铃薯Y病毒是危害马铃薯安全生产重要病毒。挖掘抗病毒新靶标，培育和种植抗病马铃薯品种是防治PVY最根本有效的方法。本研究以HC-Pro蛋白复合体中鉴定到的小GTPase蛋白Ran激活蛋白（RanGAP）为研究对象，解析了其调控PVY侵染的分子机制。结果发现：.（1）沉默NbRanGAP1和NbRanGAP2提高PVY的复制和CP积累水平，促进PVY细胞间移动速度。提前2天过表达NbRanGAP1和NbRanGAP2抑制PVY积累水平。.（2）NbRanGAP1和NbRanGAP2与HC-Pro共定位，显著提高HC-Pro在细胞核膜周边的积累，WPP功能域调控HC-Pro在细胞核膜周边的富集。NbRanGAP1和NbRanGAP2与HC-Pro不直接互作。.（3）NbRan1a和NbRan2与HC-Pro直接互作，沉默NbRan1a或NbRan2对PVY复制和侵染无明显影响，同时沉默NbRan1a和NbRan2显著降低PVY积累水平，证实NbRan1a和NbRan2正调控PVY侵染。过表达NbRan1a和NbRan2促进PVY侵染，同时NbRan1a和NbRan2与HC-Pro共定位。.（4）NbRan1a和NbRan2的激活状态对HC-Pro互作和亚细胞定位十分关键。HC-Pro与激活状态的Ran互作，不与失活状态下的Ran互作。过表达激活状态NbRan1a和NbRan2促进PVY蛋白积累，过表达失活状态的NbRan1a和NbRan2抑制PVY的积累。激活状态的NbRan1a和NbRan2可以使HC-Pro在细胞核膜周围富集。.（5）培养研究生6名，其中1名获山东省优秀毕业生，1名获山东省优秀硕士学位论文。.（6）授权国家发明专利3件，发表论文5篇，其中SCI 2篇。获中国烟草总公司科技进步三等奖1项。