乌鳢水泡病毒（SHVV）是鱼类弹状病毒的新成员，其感染导致我国乌鳢养殖业重大经济损失。Leader RNA是病毒产生的一种非编码RNA，能调节病毒增殖，是抗病毒药物及减毒疫苗的潜在靶点，但其在鱼类弹状病毒中鲜见报道。申请人前期研究发现SHVV在感染过程中产生Leader RNA，而Leader RNA能与病毒的核蛋白（N）互作，还能调节SHVV增殖。因此，本项目拟进一步展开研究：①确定Leader RNA与N蛋白互作的时空特点，研究Leader RNA与N蛋白互作对SHVV增殖的影响；②确定Leader RNA与N蛋白互作的结构域，利用结构域竞争性阻断Leader RNA与N蛋白互作，研究其对SHVV增殖的影响；③确定Leader RNA与N蛋白互作的关键位点，利用反向遗传操作技术构建关键位点的突变株，研究其增殖能力及毒力。研究结果将为抗SHVV新药靶点的发掘和新型疫苗的研制奠定理论基础。

Snakehead vesiculovirus (SHVV) is a new member of fish rhabdoviruses, and its infection has caused great economic losses in snakehead fish culture in China. Leader RNA is a kind of non-coding RNA produced by viruses, it can regulate virus multiplication and functions as potential targets of anti-viral drugs and attenuated vaccines, but little has been reported in fish rhabdoviruses. Our previous research has found that SHVV produced Leader RNA during infection, while Leader RNA could interact with viral Nucleoprotein (N) and also regulate SHVV multiplication. Therefore, this project will perform further study: ①determine the time-space characteristics of Leader RNA-N protein interaction, and study the effects of Leader RNA-N protein interaction on SHVV multiplication; ②determine the domains of Leader RNA and N protein associated with their interaction, and evaluate the effects of competitively blocking Leader RNA-N protein interaction on SHVV multiplication; ③determine the critical sites of Leader RNA and N protein associated with their interaction, generate mutants at the critical sites using reverse genetics technology, and evaluate their growth ability and pathogenicity. The obtained results will provide theoretical basis for identifying new drug sites and developing new vaccines against SHVV.