多分体负义RNA病毒（sNSV）普遍从寄主mRNA抓取帽子序列，它们怎样选择以及选择什么样的寄主mRNA作为帽子供体目前还不清楚。水稻条纹病毒（RSV）是一种重要的植物sNSV。本实验室前期以高通量测序手段鉴定了RSV的帽子序列供体，为该病毒帽子供体选择机制提供了一些新的解释。但很多解释缺乏实验证据。本项目拟在近期积累的基础上，建立“瞬时抓帽”和“双生病毒共侵染”两个新研究体系，并与传统的转基因技术相结合，从下面几个角度以实验性手段探究RSV的帽子供体选择机制：（1）“碱基配对原则”对RSV帽子供体选择的影响；（2）帽子供体二级结构对RSV帽子供体选择的影响；（3）帽子供体编码特性对RSV“抓帽”的影响；（4）寄主p-body途径和帽子结合蛋白eIF4E对RSV帽子供体选择的影响。通过创新实验体系，本项目将进一步推进RSV“抓帽机制”研究，具有重要的理论和现实意义。

Segmented negative-sense RNA viruses (sNSV) commonly snatch capped-RNA leaders from host cellular mRNAs. How they select cap donors and the molecular bases of the selection during the process of cap-snatching remain unclear. Previously, we identified the cap donors for RSV using high throughput sequencing strategies. This provided many new explanations as to the cap-donor selection of RSV. However, many of these explanations are speculative, similar to other related studies. In this study, two new experimental systems named “transient cap-snatching” and “geminivirus co-infection” systems, respectively, will be established and coupled to traditional transgenic technologies. With the availability of these systems, we will investigate the the following aspects of cap-donor selection for RSV: i) the role of base-pairing in donor selection of RSV; ii) the influence of the secondary structure of cap donors on the cap-snatching of RSV; iii) the influence of the coding capacity of cap donors on the cap-snatching of RSV; iv) the influence of the cellular p-body pathway and the cap-binding protein eIF4E on the cap-snatching of RSV. By using novel research systems, it is expected that this study will advance our understanding of the cap-snatching of RSV. Therefore, this study has both theoretical and practical significance.