Identification and characterization of novel influenza A virus proteins

2016 Fiscal Year Final Research Report

• Project/Area Number: 26460549
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Virology
• Research Institution: The University of Tokyo
• Principal Investigator: Yamayoshi Seiya 東京大学, 医科学研究所, 特任准教授 (50529534)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: インフルエンザウイルス / PB2分節 / スプライス / 新規ウイルス蛋白質

Outline of Final Research Achievements

Over the past two decades, several novel influenza viral proteins have been identified that modulate viral infections in vitro and/or in vivo. We used RT-PCR targeting viral mRNAs transcribed from the PB2 segment to look for novel viral proteins encoded by spliced mRNAs. We identified a new viral protein, termed PB2-S1, encoded by a novel spliced mRNA. PB2-S1 was detected in virus-infected cells and in cells transfected with a plasmid encoding PB2. PB2-S1 localized to mitochondria, inhibited the RIG-I-dependent interferon signaling pathway, and interfered with viral polymerase activity depending on its PB1 binding capability. The nucleotide sequences around the splicing donor and acceptor sites for PB2-S1 were highly conserved among human pre-2009 H1N1 viruses but not among human H1N1pdm and H3N2 viruses. PB2-S1-deficient viruses, however, showed similar growth kinetics in MDCK cells and virulence in mice to those of wild-type virus.

Free Research Field

ウイルス学