Department of Microbiology, Kanazawa Medical University School of Medicine, 1-1 Daigaku, Uchinada, Ishikawa 920-0293, Japan.
Virology. 2012 Nov 10;433(1):167-75. doi: 10.1016/j.virol.2012.08.010. Epub 2012 Aug 22.
CM2 is the second membrane protein of influenza C virus and possesses a conserved motif for N-glycosylation. To investigate the role(s) of CM2 glycosylation in the virus replication, we generated rN11A, a recombinant influenza C virus lacking the glycosylation site. The rN11A virus grew less efficiently than the wild-type (WT) virus, although the biochemical characteristics of the mutant CM2 were similar to those of authentic CM2. The amount of the genome (GFP-vRNA) in the CM2-N11A-virus-like particles (VLPs) was 13% of that found in WT-VLPs. The incoming GFP-vRNA was less efficiently transported to the nucleus in CM2-N11A-VLP-infected cells than WT-VLP-infected cells, leading to the reduced reporter gene expression in CM2-N11A-VLP-infected cells. Thus the glycosylation of CM2 is required for efficient replication of influenza C virus, and the obtained findings confirmed and extended the previous observation that CM2 is involved in the genome packaging and uncoating processes.
CM2 是丙型流感病毒的第二种膜蛋白，具有保守的 N-糖基化位点。为了研究 CM2 糖基化在病毒复制中的作用，我们生成了 rN11A，这是一种缺乏糖基化位点的重组丙型流感病毒。rN11A 病毒的生长效率低于野生型（WT）病毒，尽管突变体 CM2 的生化特性与真实的 CM2 相似。CM2-N11A 病毒样颗粒（VLPs）中的基因组（GFP-vRNA）数量是 WT-VLPs 的 13%。在 CM2-N11A-VLP 感染的细胞中，进入的 GFP-vRNA 向核内的运输效率低于 WT-VLP 感染的细胞，导致 CM2-N11A-VLP 感染的细胞中报告基因表达减少。因此，CM2 的糖基化对于丙型流感病毒的有效复制是必需的，并且获得的发现证实并扩展了之前的观察结果，即 CM2 参与基因组包装和脱壳过程。
