Glycosylation of CM2 is important for efficient replication of influenza C virus

• Published in: Virology (New York, N.Y.) Vol. 433; no. 1; pp. 167 - 175
• Main Authors: Okuwa, Takako, Muraki, Yasushi, Himeda, Toshiki, Ohara, Yoshiro
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 10.11.2012
• Subjects: Biochemical characteristics; Cell Line; Cell Nucleus - virology; CM2 protein; Conserved Sequence; Gammainfluenzavirus - physiology; Gene Expression; Genes, Reporter; Genomes; Glycosylation; Green Fluorescent Proteins; Humans; Infectious Disease; Influenza C; Influenza C virus; Membrane proteins; Mutation; Nuclei; Packaging; Protein Transport; Replication; Reporter gene; Reverse Genetics; Uncoating; Viral Matrix Proteins - genetics; Virus Assembly - genetics; Virus Replication - genetics; Uncoating; Packaging; Replication; Influenza C virus; CM2 protein
• ISSN: 0042-6822; 1096-0341
• DOI: 10.1016/j.virol.2012.08.010

Abstract 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.