Differential role of the influenza A virus polymerase PA subunit for vRNA and cRNA promoter binding.

Journal article

The RNA polymerase of influenza A virus is a heterotrimeric complex of PB1, PB2 and PA subunits that is required for transcription and replication of the viral genome. Here, we demonstrate a differential requirement of the PA subunit for binding to the vRNA and cRNA promoters--specifically, PA is more important for binding to the cRNA than the vRNA promoter. Furthermore, five point mutations were identified in the L163-I178 region of PA, which resulted in an inhibition of polymerase activity when provided with a cRNA compared to vRNA promoter. Cross-linking studies suggested that this inhibition was due to a reduction in promoter binding of the mutant polymerases to the cRNA promoter. We conclude that the L163-I178 region of PA is directly or indirectly involved in cRNA promoter binding and suggest a novel function for PA in modulating promoter binding.

Authors: Maier, H; Kashiwagi, T; Hara, K; Brownlee, G

• Publication status: Published
• Journal: Virology
• Volume: 370
• Issue: 1
• Pages: 194-204
• Publication date: 2008-01-01
• DOI: 10.1016/j.virol.2007.08.029
• EISSN: 1096-0341
• ISSN: 0042-6822
• Language: English
• Keywords: DNA-Directed RNA Polymerases; Humans; Transcription, Genetic; RNA, Complementary; Virus Replication; Promoter Regions, Genetic; RNA, Viral; Viral Proteins; Influenza A virus; RNA Replicase; Cell Line; Point Mutation