马铃薯是我国重要的粮食作物。病毒病是导致种薯品质退化和单位面积产量下降的重要因素，其中以马铃薯Y病毒最为严重。种植抗病毒马铃薯品种是防治病毒病最根本方法。马铃薯Y病毒编码的辅助成分－蛋白酶（Helper component-proteinase, HCpro)是一种多功能蛋白，是激发或克服马铃薯Ny基因介导抗性的关键因素。本项目拟研究HCpro的RNA沉默功能和HCpro在序列和结构上模拟寄主与Ny介导抗性的关系，分析接种不同HCpro突变体在含Ny基因马铃薯上基因表达差异来探讨HCpro克服或引起Ny介导抗性中的信号途径，筛选并鉴定不同HCpro在含Ny基因马铃薯上互作蛋白差异并探讨其作用。综合分析HCpro模拟寄主在Ny介导的抗性过程中的作用机制。本研究结果将有助于进一步理解病毒－寄主的互作机制，在实践上可为培育抗病毒品种提供理论依据。

Potato virus Y (PVY) is the most common and economically harmful virus infecting the fourth important crop-potato. Planting virus-resistant potato cultivars is the most effective way to control PVY. However, some PVY isolates have overcome the corresponding resistance gene by mutations and/or recombination. It showed that the multifunction protein helper component-proteinase (HCpro) encoded by PVY is required for eliciting or overcoming Ny-mediated resistance. The recognition mechanism is still unclear. Here, we try to understand the link between RNA silencing suppression ability of HCpro mutants and their responses on Ny-carrying potatoes, to characterize the role of the basic amino acid sequences in HCpro cellular localization and in mimicking host conserved motif, to screen the gene expression changes in potato leaves inoculated with different mutants, to screen and identify host proteins interacted with different HCpro. In together, with these results it can help us to understand the recognition mechanism between HCpro and Ny resistance gene, moreover, the role of HCpro in mimicking host protein will be clear.