马铃薯Y病毒（PVY）是世界范围内能够侵染多种植物并造成严重经济危害的植物病毒。克隆和鉴定寄主中的抗病基因是对病害进行绿色防控和分子育种的基础。申请人在前期研究中发现烟草钙联蛋白基因（NtCNX）是PVY来源vsiRNA的靶基因，但其互作的生物学意义有待进一步研究。本项目针对烟草NtCNX基因与PVYvsiRNA互作对植物抗病性以及病毒致病性的作用这一科学问题，根据siRNA在PVY基因组产生的区域，对PVY基因组局部进行密码子改造并构建侵染性克隆，从而突变特定vsiRNA的序列使其不再靶向NtCNX基因，进一步分析PVY突变体对寄主致病性的影响，阐明vsiRNA在病毒致病过程中的作用。进一步超量表达和基因编辑等技术，深入分析烟草NtCNX基因超量表达和敲除后烟草对PVY抗性的变化，阐明NtCNX基因对寄主抗病性的影响,为后期的抗病基因克隆和分子育种奠定基础。

Potato virus Y (PVY) is a worldwide economically important pathogen of potato, tobacco, tomato and other crops causing significant yield losses and quality reduction. Identification and isolation plant genes confers resistance to PVY is the key for green prevention and control and modular breeding. We have previously found that virus-derived siRNAs (vsiRNAs) from PVY genome targets tobacco calnexin, (NtCNX ), suggesting that the interactions between NtCNX and PVY-derived siRNA is very important for the plant resistance to PVY infection, yet the molecular mechanism of the interactions still to be explored. On the basis of our preliminary work, PVY infectious clone will be constructed based on the amino acid codon degeneracy that the vsiRNA sequence will be mutated according to the region of the PVY genome that derived the vsiRNA. Then the pathogenicity of the PVY infectious clone will be compared with the wild type to elaborate the role of vsiRNA on PVY pathogenicity to the host. Next, we will use gene overexpression and gene editing technology to verificate the role of NtCNX on the plant resistance to PVY infection. . This research will uncover the molecular mechanism of interactions between NtCNX and PVY-derived vsiRNA and laying the foundation for PVY disease control and breeding resistant varies.