Generation and characterization of influenza A viruses with altered polymerase fidelity

Nat Commun. 2014 Sep 3:5:4794. doi: 10.1038/ncomms5794.

Abstract

Genetic diversity of influenza A viruses (IAV) acquired through the error-prone RNA-dependent RNA polymerase (RdRP) or through genetic reassortment enables perpetuation of IAV in humans through epidemics or pandemics. Here, to assess the biological significance of genetic diversity acquired through RdRP, we characterize an IAV fidelity variant derived from passaging a seasonal H3N2 virus in the presence of ribavirin, a purine analogue that increases guanosine-to-adenosine mutations. We demonstrate that a single PB1-V43I mutation increases selectivity to guanosine in A/Wuhan/359/95 (H3N2) and A/Vietnam/1203/04 (H5N1) viruses. The H5N1 PB1-V43I-recombinant virus replicates to comparable titres as the wild-type virus in vitro or in the mouse lungs. However, a decrease in viral population diversity at day 3 post inoculation is associated with a tenfold reduced lethality and neurotropism in mice. Applying a fidelity variant with reduced mutational frequency, we provide direct experimental evidence for the role of genetic diversity in IAV pathogenesis.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine / genetics
  • Animals
  • Antiviral Agents / pharmacology
  • Drug Resistance, Viral / genetics
  • Female
  • Genetic Variation
  • Guanosine / genetics
  • Influenza A Virus, H3N2 Subtype / genetics*
  • Influenza A Virus, H3N2 Subtype / pathogenicity
  • Influenza A Virus, H5N1 Subtype / genetics*
  • Influenza A Virus, H5N1 Subtype / pathogenicity
  • Lung / pathology
  • Lung / virology
  • Mice
  • Mice, Inbred BALB C
  • Mutation / drug effects*
  • Orthomyxoviridae Infections / mortality
  • Orthomyxoviridae Infections / pathology
  • Orthomyxoviridae Infections / virology
  • RNA-Dependent RNA Polymerase / genetics*
  • RNA-Dependent RNA Polymerase / metabolism
  • Reassortant Viruses / genetics*
  • Reassortant Viruses / pathogenicity
  • Ribavirin / pharmacology
  • Survival Analysis
  • Viral Proteins / genetics*
  • Viral Proteins / metabolism
  • Viral Tropism

Substances

  • Antiviral Agents
  • Viral Proteins
  • Guanosine
  • Ribavirin
  • RNA-Dependent RNA Polymerase
  • Adenosine