Naturally occurring mutations in the PA gene are key contributors to increased virulence of pandemic H1N1/09 influenza virus in mice

We examined the molecular basis of virulence of pandemic H1N1/09 influenza viruses by reverse genetics based on two H1N1/09 virus isolates (A/California/04/2009 [CA04] and A/swine/Shandong/731/2009 [SD731]) with contrasting pathogenicities in mice. We found that four amino acid mutations (P224S in t...

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Bibliographic Details
Main Authors: Sun, Y., Xu, Q., Shen, Y., Liu, L., Wei, K., Sun, H., Pu, J., Chang, K.-C., Liu, J.
Format: Article
Published: American Society for Microbiology 2014
Online Access:https://eprints.nottingham.ac.uk/43920/
Description
Summary:We examined the molecular basis of virulence of pandemic H1N1/09 influenza viruses by reverse genetics based on two H1N1/09 virus isolates (A/California/04/2009 [CA04] and A/swine/Shandong/731/2009 [SD731]) with contrasting pathogenicities in mice. We found that four amino acid mutations (P224S in the PA protein [PA-P224S], PB2-T588I, NA-V106I, and NS1-I123V) contributed to the lethal phenotype of SD731. In particular, the PA-P224S mutation when combined with PA-A70V in CA04 drastically reduced the virus's 50% mouse lethal dose (LD50), by almost 1,000-fold.