Sakai Yusuke, Kawachi Kengo, Terada Yutaka, Omori Hiroko, Matsuura Yoshiharu, Kamitani Wataru
Laboratory of Clinical Research on Infectious Diseases, Osaka, Japan; Laboratory of Veterinary Pathology, Joint Faculty of Veterinary Medicine, Yamaguchi University, Yamaguchi, Japan.
Laboratory of Clinical Research on Infectious Diseases, Osaka, Japan; Department of Molecular Virology, Osaka, Japan.
Virology. 2017 Oct;510:165-174. doi: 10.1016/j.virol.2017.07.019. Epub 2017 Jul 21.
Infection with coronavirus rearranges the host cell membrane to assemble a replication/transcription complex in which replication of the viral genome and transcription of viral mRNA occur. Although coexistence of nsp3 and nsp4 is known to cause membrane rearrangement, the mechanisms underlying the interaction of these two proteins remain unclear. We demonstrated that binding of nsp4 with nsp3 is essential for membrane rearrangement and identified amino acid residues in nsp4 responsible for the interaction with nsp3. In addition, we revealed that the nsp3-nsp4 interaction is not sufficient to induce membrane rearrangement, suggesting the participation of other factors such as host proteins. Finally, we showed that loss of the nsp3-nsp4 interaction eliminated viral replication by using an infectious cDNA clone and replicon system of SARS-CoV. These findings provide clues to the mechanism of the replication/transcription complex assembly of SARS-CoV and could reveal an antiviral target for the treatment of betacoronavirus infection.
冠状病毒感染会重新排列宿主细胞膜，以组装一个复制/转录复合体，病毒基因组的复制和病毒mRNA的转录在其中发生。尽管已知nsp3和nsp4共存会导致膜重排，但这两种蛋白质相互作用的潜在机制仍不清楚。我们证明nsp4与nsp3的结合对于膜重排至关重要，并确定了nsp4中负责与nsp3相互作用的氨基酸残基。此外，我们发现nsp3-nsp4相互作用不足以诱导膜重排，这表明其他因素如宿主蛋白也参与其中。最后，我们利用严重急性呼吸综合征冠状病毒（SARS-CoV）的感染性cDNA克隆和复制子系统表明，nsp3-nsp4相互作用的丧失消除了病毒复制。这些发现为SARS-CoV复制/转录复合体组装机制提供了线索，并可能揭示治疗β冠状病毒感染的抗病毒靶点。
