Plum Island Animal Disease Center, ARS, USDA, Greenport, New York, USA.
J Virol. 2013 Jun;87(12):6794-803. doi: 10.1128/JVI.00448-13. Epub 2013 Apr 10.
Foot-and-mouth disease virus (FMDV), the causative agent of foot-and-mouth disease, is an Aphthovirus within the Picornaviridae family. During infection with FMDV, several host cell membrane rearrangements occur to form sites of viral replication. FMDV protein 2C is part of the replication complex and thought to have multiple roles during virus replication. To better understand the role of 2C in the process of virus replication, we have been using a yeast two-hybrid approach to identify host proteins that interact with 2C. We recently reported that cellular Beclin1 is a natural ligand of 2C and that it is involved in the autophagy pathway, which was shown to be important for FMDV replication. Here, we report that cellular vimentin is also a specific host binding partner for 2C. The 2C-vimentin interaction was further confirmed by coimmunoprecipitation and immunofluorescence staining to occur in FMDV-infected cells. It was shown that upon infection a vimentin structure forms around 2C and that this structure is later resolved or disappears. Interestingly, overexpression of vimentin had no effect on virus replication; however, overexpression of a truncated dominant-negative form of vimentin resulted in a significant decrease in viral yield. Acrylamide, which causes disruption of vimentin filaments, also inhibited viral yield. Alanine scanning mutagenesis was used to map the specific amino acid residues in 2C critical for vimentin binding. Using reverse genetics, we identified 2C residues that are necessary for virus growth, suggesting that the interaction between FMDV 2C and cellular vimentin is essential for virus replication.
口蹄疫病毒(FMDV)是口蹄疫的病原体,属于小 RNA 病毒科的口疮病毒属。在感染 FMDV 时,宿主细胞膜会发生几种重排,形成病毒复制的部位。FMDV 蛋白 2C 是复制复合物的一部分,被认为在病毒复制过程中有多种作用。为了更好地理解 2C 在病毒复制过程中的作用,我们一直使用酵母双杂交方法来鉴定与 2C 相互作用的宿主蛋白。我们最近报道细胞 Beclin1 是 2C 的天然配体,它参与自噬途径,该途径对 FMDV 复制很重要。在这里,我们报告细胞波形蛋白也是 2C 的特定宿主结合伴侣。2C-波形蛋白的相互作用通过共免疫沉淀和免疫荧光染色进一步证实,在 FMDV 感染的细胞中发生。结果表明,感染后,波形蛋白结构围绕 2C 形成,随后该结构被解决或消失。有趣的是,波形蛋白的过表达对病毒复制没有影响;然而,过表达截断的显性负形式的波形蛋白导致病毒产量显著降低。丙烯酰胺会破坏波形蛋白丝,也会抑制病毒产量。使用丙氨酸扫描诱变来映射 2C 中对波形蛋白结合至关重要的特定氨基酸残基。使用反向遗传学,我们鉴定了 2C 中对病毒生长必不可少的残基,表明 FMDV 2C 与细胞波形蛋白之间的相互作用对于病毒复制是必不可少的。