Zhu Jie, Miao Qiuhong, Guo Hongyuan, Tang Aoxing, Dong Dandan, Tang Jingyu, Wang Fang, Tong Guangzhi, Liu Guangqing
Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China.
Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai, 200241, China; Laboratory of Virology, Wageningen University and Research, Wageningen, 6708 PB, the Netherlands.
Virol Sin. 2022 Feb;37(1):48-59. doi: 10.1016/j.virs.2022.01.004. Epub 2022 Jan 12.
Rabbit hemorrhagic disease virus (RHDV) is a member of the Caliciviridae family and cannot be propagated in vitro, which has impeded the progress of investigating its replication mechanism. Construction of an RHDV replicon system has recently provided a platform for exploring RHDV replication in host cells. Here, aided by this replicon system and using two-step affinity purification, we purified the RHDV replicase and identified its associated host factors. We identified rabbit nucleolin (NCL) as a physical link, which mediating the interaction between other RNA-dependent RNA polymerase (RdRp)-related host proteins and the viral replicase RdRp. We found that the overexpression or knockdown of NCL significantly increased or severely impaired RHDV replication in RK-13 cells, respectively. NCL was identified to directly interact with RHDV RdRp, p16, and p23. Furthermore, NCL knockdown severely impaired the binding of RdRp to RdRp-related host factors. Collectively, these results indicate that the host protein NCL is essential for RHDV replication and acts as a physical link between viral replicase and host proteins.
兔出血症病毒（RHDV）是杯状病毒科的成员，无法在体外增殖，这阻碍了对其复制机制研究的进展。最近构建的RHDV复制子系统为探索RHDV在宿主细胞中的复制提供了一个平台。在此，借助该复制子系统并采用两步亲和纯化法，我们纯化了RHDV复制酶并鉴定了其相关的宿主因子。我们鉴定出兔核仁素（NCL）作为一种物理连接物，它介导其他依赖RNA的RNA聚合酶（RdRp）相关宿主蛋白与病毒复制酶RdRp之间的相互作用。我们发现，在RK - 13细胞中，NCL的过表达或敲低分别显著增加或严重损害了RHDV的复制。已确定NCL直接与RHDV RdRp、p16和p23相互作用。此外，NCL敲低严重损害了RdRp与RdRp相关宿主因子的结合。总的来说，这些结果表明宿主蛋白NCL对RHDV复制至关重要，并作为病毒复制酶与宿主蛋白之间的物理连接物发挥作用。
