Department of Biochemistry and Molecular Biology, School of Basic Medical Science, Ningxia Medical University, Yinchuan, China.
Department of Clinical Medicine, School of Clinical Medicine, Ningxia Medical University, Yinchuan, China.
Mol Microbiol. 2024 Jun;121(6):1127-1147. doi: 10.1111/mmi.15263. Epub 2024 Apr 17.
Minute virus of canines (MVC) belongs to the genus Bocaparvovirus (formerly Bocavirus) within the Parvoviridae family and causes serious respiratory and gastrointestinal symptoms in neonatal canines worldwide. A productive viral infection relies on the successful recruitment of host factors for various stages of the viral life cycle. However, little is known about the MVC-host cell interactions. In this study, we identified that two cellular proteins (Hsc70 and Hsp70) interacted with NS1 and VP2 proteins of MVC, and both two domains of Hsc70/Hsp70 were mediated for their interactions. Functional studies revealed that Hsp70 was induced by MVC infection, knockdown of Hsc70 considerably suppressed MVC replication, whereas the replication was dramatically promoted by Hsp70 knockdown. It is interesting that low amounts of overexpressed Hsp70 enhanced viral protein expression and virus production, but high amounts of Hsp70 overexpression weakened them. Upon Hsp70 overexpressing, we observed that the ubiquitination of viral proteins changed with Hsp70 overexpression, and proteasome inhibitor (MG132) restored an accumulation of viral proteins. In addition, we verified that Hsp70 family inhibitors remarkably decreased MVC replication. Overall, we identified Hsc70 and Hsp70 as interactors of MVC NS1 and VP2 proteins and were involved in MVC replication, which may provide novel targets for anti-MVC approach.
犬微小病毒 (MVC) 属于细小病毒科细小病毒属，可引起全球新生幼犬严重的呼吸道和胃肠道症状。病毒的有效感染依赖于宿主因子在病毒生命周期的各个阶段的成功募集。然而，对于 MVC-宿主细胞的相互作用知之甚少。在这项研究中，我们鉴定了两种细胞蛋白（Hsc70 和 Hsp70）与 MVC 的 NS1 和 VP2 蛋白相互作用，并且 Hsc70/Hsp70 的两个结构域都介导了它们的相互作用。功能研究表明，Hsp70 被 MVC 感染诱导，Hsc70 的敲低显著抑制 MVC 的复制，而 Hsp70 的敲低则显著促进复制。有趣的是，少量过表达的 Hsp70 增强了病毒蛋白的表达和病毒产生，但大量过表达的 Hsp70 则削弱了它们。在 Hsp70 过表达时，我们观察到病毒蛋白的泛素化随 Hsp70 过表达而改变，蛋白酶体抑制剂 (MG132) 恢复了病毒蛋白的积累。此外，我们验证了 Hsp70 家族抑制剂显著降低了 MVC 的复制。总之，我们鉴定了 Hsc70 和 Hsp70 是 MVC NS1 和 VP2 蛋白的相互作用蛋白，并参与 MVC 的复制，这可能为抗 MVC 方法提供新的靶点。
