This is not the latest version of this item. The latest version can be found here.
A point mutation in the polymerase protein PB2 allows a reassortant H9N2 influenza isolate of wild-bird origin to replicate in human cells
Name
nihms782150.pdf
Description
Accepted version
Size
524.62 KB
Format
Adobe PDF
Checksum (MD5)
a207a9ee8d294cc11f88e547fbd8c5c4
Author(s)
Hussein, Islam TM
Ma, Eric J
Hill, Nichola J
Meixell, Brandt W
Lindberg, Mark
Albrecht, Randy A
Bahl, Justin
Runstadler, Jonathan A
Date Issued
2016
Journal
Infection, Genetics and Evolution
Publisher
Elsevier BV
Citation
Hussein, I. T., et al. "A Point Mutation in the Polymerase Protein Pb2 Allows a Reassortant H9n2 Influenza Isolate of Wild-Bird Origin to Replicate in Human Cells." Infect Genet Evol 41 (2016): 279-88.
Version
Author's final manuscript
Abstract
© 2016. H9N2 influenza A viruses are on the list of potentially pandemic subtypes. Therefore, it is important to understand how genomic reassortment and genetic polymorphisms affect phenotypes of H9N2 viruses circulating in the wild bird reservoir. A comparative genetic analysis of North American H9N2 isolates of wild bird origin identified a naturally occurring reassortant virus containing gene segments derived from both North American and Eurasian lineage ancestors. The PB2 segment of this virus encodes 10 amino acid changes that distinguish it from other H9 strains circulating in North America. G590S, one of the 10 amino acid substitutions observed, was present in ~12% of H9 viruses worldwide. This mutation combined with R591 has been reported as a marker of pathogenicity for human pandemic 2009 H1N1 viruses. Screening by polymerase reporter assay of all the natural polymorphisms at these two positions identified G590/K591 and S590/K591 as the most active, with the highest polymerase activity recorded for the SK polymorphism. Rescued viruses containing these two polymorphic combinations replicated more efficiently in MDCK cells and they were the only ones tested that were capable of establishing productive infection in NHBE cells. A global analysis of all PB2 sequences identified the K591 signature in six viral HA/NA subtypes isolated from several hosts in seven geographic locations. Interestingly, introducing the K591 mutation into the PB2 of a human-adapted H3N2 virus did not affect its polymerase activity. Our findings demonstrate that a single point mutation in the PB2 of a low pathogenic H9N2 isolate could have a significant effect on viral phenotype and increase its propensity to infect mammals. However, this effect is not universal, warranting caution in interpreting point mutations without considering protein sequence context.
Terms of Use
Creative Commons Attribution-NonCommercial-NoDerivs License
Persistent DSpace Link
DOI of Published Version
10.1016/J.MEEGID.2016.04.011
