John and Jeanne Rowe Center for Research in Virology, Morgridge Institute for Research, Madison, WI, 53715, United States; Institute for Molecular Virology, University of Wisconsin-Madison, Madison, WI, 53706, United States; McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI, 53705, United States.
Curr Opin Virol. 2021 Dec;51:74-79. doi: 10.1016/j.coviro.2021.09.008. Epub 2021 Sep 30.
The nodavirus flock house virus recently provided a well-characterized model for the first cryo-electron microscope tomography of membrane-bound, positive-strand RNA ((+)RNA) virus genome replication complexes (RCs). The resulting first views of RC organization and complementary biochemical results showed that the viral RNA replication vesicle is tightly packed with the dsRNA genomic RNA replication intermediate, and that (+)ssRNA replication products are released through the vesicle neck to the cytosol through a 12-fold symmetric ring or crown of multi-functional viral RNA replication proteins, which likely also contribute to viral RNA synthesis. Subsequent studies identified similar crown-like RNA replication protein complexes in alphavirus and coronavirus RCs, indicating related mechanisms across highly divergent (+)RNA viruses. As outlined in this review, these results have significant implications for viral function, evolution and control.
小核糖核酸病毒浮置屋病毒最近为正链 RNA（(+)RNA）病毒基因组复制复合物（RC）的首次冷冻电镜断层扫描提供了一个很好的模式。由此产生的 RC 组织的第一个观点和互补的生化结果表明，病毒 RNA 复制泡与 dsRNA 基因组 RNA 复制中间体紧密包装，并且(+)ssRNA 复制产物通过泡颈释放到细胞质中，通过 12 重对称环或多功能病毒 RNA 复制蛋白的冠，这可能也有助于病毒 RNA 的合成。随后的研究在甲病毒和冠状病毒 RC 中鉴定了类似的冠状 RNA 复制蛋白复合物，表明高度不同的(+)RNA 病毒具有相关的机制。正如本综述所概述的，这些结果对病毒功能、进化和控制具有重要意义。
