甘蔗线条花叶病毒（SCSMV）是引起甘蔗花叶病的一种主要病原。SCSMV编码的P1蛋白是RNA沉默 抑制子，在SCSMV抑制寄主的RNA沉默防御中发挥关键作用，但其作用机制尚未清楚。与寄主蛋白互作是RNA沉默抑制子发挥其抑制作用的主要途径之一，因此鉴定与病毒RNA沉默抑制子互作的寄主蛋白是研究抑制子作用机制的一个重要方法。本项目拟以SCSMV的自然寄主甘蔗为研究材料，首先通过酵母双杂交和双分子荧光互补技术筛选鉴定与SCSMV P1蛋白互作的甘蔗蛋白；然后利用农杆菌共浸润瞬时表达系统分析互作蛋白对P1抑制子活性的影响，找出对P1抑制子活性具有显著影响的关键互作蛋白；最后利用过表达和CRISPR/Cas9基因编辑技术结合抗病性鉴定解析关键互作蛋白在SCSMV侵染过程中的功能，进而从寄主互作蛋白角度阐明SCSMV P1抑制RNA沉默的机制。研究结果将为SCSMV的科学防控提供理论依据。

Sugarcane streak mosaic virus (SCSMV) is a major pathogen of sugarcane mosaic disease. The P1 protein encoded by SCSMV is an RNA silencing suppressor, which plays a key role in suppressing the host's RNA silencing defense. However, its mechanism is not yet clear. Interaction with host proteins is one of the main pathways for RNA silencing suppressors to exert their suppression functions. Therefore, identifying host proteins that interact with viral RNA silencing suppressors is an important method to study the mechanism of suppressors. This project intends to use sugarcane, the natural host of SCSMV, as the research material. First, the sugarcane proteins that interact with SCSMV P1 protein will be screened and identified by yeast two-hybrid and bimolecular fluorescence complementation assays. Then, the effects of interacting proteins on the suppressor activity of P1 will be analyzed by the Agrobacterium co-infiltration transient expression system. And the key interacting proteins with significant effects on the suppressor activity of P1 will be found out. Finally, the function of the key interacting proteins in the process of SCSMV infection will be analyzed by using overexpression and CRISPR/Cas9 genome editing technology combined with disease resistance identification, so as to clarify the RNA silencing suppression mechanism of SCSMV P1 from the perspective of host interacting proteins. The results will provide theoretical basis for the scientific prevention and control of SCSMV.