Studies on the mechanisms involved in the host range restriction of influenza A viruses

2015 Fiscal Year Final Research Report

• Project/Area Number: 25460581
• 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 (2015); Iwate University (2013-2014)
• Principal Investigator: Imai Masaki 東京大学, 医科学研究所, 准教授 (30333363)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 鳥インフルエンザウイルス / ヘマグルチニン（HA）蛋白質 / 安定性 / レセプター特異性 / 膜融合活性 / 感染性

Outline of Final Research Achievements

A change in the receptor binding properties of the hemagglutinin (HA) of avian influenza viruses is a critical step in their adaptation to human hosts. Indeed, the 1918 H1N1, 1957 H2N2, and 1968 H3N2 pandemic strains all exhibited human-type receptor-binding preference despite the fact that the HAs of these viruses were derived from avian species. To understand the mechanisms by which influenza viruses adapt to the human host, we analyzed the stability of HA proteins from H1, H2, and H3 avian influenza viruses, which possess mutations that confer human-type receptor recognition. We observed that mutations conferring human-type receptor recognition decreased slightly the HA protein stability of H1 avian virus, but not affect the HA stability of H2 and H3 avian viruses. These results suggest that H2 and H3 avian influenza viruses may be relatively easily able to acquire the mutation(s) necessary to confer human-type receptor recognition

Free Research Field

ウイルス学