Acetylation of the viral histone-like protein, nucleoprotein, in influenza virus affects viral transcriptional activity

2016 Fiscal Year Final Research Report

• Project/Area Number: 26460562
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Virology
• Research Institution: Tokushima Bunri University
• Principal Investigator: Hatakeyama Dai 徳島文理大学, 薬学部, 准教授 (20514821)
• Co-Investigator(Renkei-kenkyūsha): SHOJI Masaki 徳島文理大学, 薬学部, 助教 (00636821) ; KUZUHARA Takashi 徳島文理大学, 薬学部, 教授 (00260513) ; 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 / ヌクレオプロテインNP / アセチル化修飾 / GCN5 / PCAF / 翻訳後修飾

Outline of Final Research Achievements

Viral RNA of influenza virus interacts with nucleoprotein (NP), whose function corresponds to that of eukaryotic histones. Here, we show that influenza virus NP undergoes acetylation, and this modification affects viral polymerase activities. Western blot analysis using anti-acetyl-lysine antibody indicated that viral NP was acetylated in infected cells. Eukaryotic GCN5 and PCAF acetylated NP in vitro. Mass spectrometry identified 3 lysine residues as acetylation targets in host cells, and suggested that K31 and K90 were acetylated by PCAF and GCN5, respectively. Acetylation levels of NP were significantly decreased using RNAi against GCN5 and PCAF in infected cells. Viral polymerase activities were increased by the RNAi against PCAF but decreased by that against GCN5, suggesting that acetylation of different target lysine residues caused these opposing results. Our findings suggested that epigenetic control by acetylation of NP is important for polymerase activity in influenza virus.

Free Research Field

ウイルス学，生化学，分子生物学