Zou Weixuan, Zhou Xusha, Wang Lei, Zhou Grace Guoying, Chen Xiaoqing
School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, China.
Shenzhen International Institute for Biomedical Research, Shenzhen, China.
Front Microbiol. 2020 Apr 23;11:717. doi: 10.3389/fmicb.2020.00717. eCollection 2020.
Among 29 distinct miRNAs expressed by the herpes simplex virus-1 (HSV-1) during lytic infection, miR-H11, together with miR-H1 to miR-H8 are reported to locate in the RNA-induced silencing complex (RISC). miR-H11 is encoded within viral origins of replication and lies entirely within the origins of replication. However, the roles of this miRNA derived from lytic infection with HSV-1 remain unclear. Using the advantage of vaccinia virus protein VP55 (VP55)-mediated degradation of miRNAs, we constructed a recombinant virus expressing VP55 (R5502) to demonstrate that: (1) accumulation of miR-H11 from R5502 was reduced by 540-fold versus that in cells infected with wild-type HSV-1, but miR-H1 to miR-H8 which also located in the RISC were not reduced significantly from R5502 compare with wild-type HSV-1; (2) downregulation of miR-H11 from R5502 infected cells results in markedly lower viral DNA synthesis compared with wild-type HSV-1; and (3) downregulation of miR-H11 also restricted viral spreading, and resulted in low accumulation of representative viral proteins and viral yields. The findings were confirmed through either using of a miR-H11 inhibitor or pre-transfection of a plasmid expressing VP55. These data suggest that miR-H11 plays a currently unidentified role in maintaining sufficient viral DNA synthesis during the course of viral infection.
在单纯疱疹病毒1型（HSV-1）裂解感染期间表达的29种不同的微小RNA（miRNA）中，据报道miR-H11与miR-H1至miR-H8一起定位于RNA诱导沉默复合体（RISC）中。miR-H11编码于病毒复制起点内，且完全位于复制起点内。然而，这种源自HSV-1裂解感染的miRNA的作用仍不清楚。利用痘苗病毒蛋白VP55介导的miRNA降解优势，我们构建了一种表达VP55的重组病毒（R5502），以证明：（1）与感染野生型HSV-1的细胞相比，R5502中miR-H11的积累减少了540倍，但同样定位于RISC中的miR-H1至miR-H8与野生型HSV-1相比，在R5502中并未显著减少；（2）与野生型HSV-1相比，R5502感染细胞中miR-H11的下调导致病毒DNA合成明显降低；（3）miR-H11的下调也限制了病毒传播，并导致代表性病毒蛋白积累减少和病毒产量降低。通过使用miR-H11抑制剂或预先转染表达VP55的质粒，这些发现得到了证实。这些数据表明，miR-H11在病毒感染过程中维持足够的病毒DNA合成方面发挥着目前尚未明确的作用。
