tetano
Editor, Senior Moderator
J Virol. 2013 Jul 24. [Epub ahead of print]
Influenza A virus PB1-F2 protein expression is regulated in a strain-specific manner by sequences located downstream of the PB1-F2 initiation codon.
Buehler J, Navi D, Lorusso A, Vincent A, Lager K, Miller CL.
Source
From the Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, 50011, USA.
Abstract
Translation of influenza A virus PB1-F2 occurs in a second open reading frame (ORF) of the PB1 gene segment. PB1-F2 has been implicated in regulation of polymerase activity, immunopathology, susceptibility to secondary bacterial infection, and induction of apoptosis. Experimental evidence of PB1-F2 molecular function during infection has been primarily collected from human and avian viral isolates. As the 2009 H1N1 (H1N1pdm09) strain highlighted, some swine-derived influenza viruses have the capacity to infect human hosts and emerge as a pandemic. Understanding the impact that virulence factors from swine isolates have on both human and swine health could aid in early identification of viruses with pandemic potential. Studies examining PB1-F2 from swine isolates have focused primarily on H1N1pdm09, which does not encode PB1-F2, but was engineered to encode a full-length PB1-F2 ORF to assess the impact on viral replication and pathogenicity. However, experimental evidence of PB1-F2 protein expression from swine-lineage viruses has not been demonstrated. Here we reveal that during infection, PB1-F2 expression levels are substantially different between swine and human influenza viruses. We provide evidence that PB1-F2 expression is regulated at the translational level, with very low levels of PB1-F2 expression from swine-lineage viruses relative to a human isolate PB1-F2. Translational regulation of PB1-F2 expression was partially mapped to two independent regions within the PB1 mRNA, located downstream of the PB1-F2 start site. Our data suggest that encoding a full-length PB1-F2 ORF may not be predictive of PB1-F2 expression in infected cells for all influenza A viruses.
PMID:
23885074
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/23885074
Influenza A virus PB1-F2 protein expression is regulated in a strain-specific manner by sequences located downstream of the PB1-F2 initiation codon.
Buehler J, Navi D, Lorusso A, Vincent A, Lager K, Miller CL.
Source
From the Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, 50011, USA.
Abstract
Translation of influenza A virus PB1-F2 occurs in a second open reading frame (ORF) of the PB1 gene segment. PB1-F2 has been implicated in regulation of polymerase activity, immunopathology, susceptibility to secondary bacterial infection, and induction of apoptosis. Experimental evidence of PB1-F2 molecular function during infection has been primarily collected from human and avian viral isolates. As the 2009 H1N1 (H1N1pdm09) strain highlighted, some swine-derived influenza viruses have the capacity to infect human hosts and emerge as a pandemic. Understanding the impact that virulence factors from swine isolates have on both human and swine health could aid in early identification of viruses with pandemic potential. Studies examining PB1-F2 from swine isolates have focused primarily on H1N1pdm09, which does not encode PB1-F2, but was engineered to encode a full-length PB1-F2 ORF to assess the impact on viral replication and pathogenicity. However, experimental evidence of PB1-F2 protein expression from swine-lineage viruses has not been demonstrated. Here we reveal that during infection, PB1-F2 expression levels are substantially different between swine and human influenza viruses. We provide evidence that PB1-F2 expression is regulated at the translational level, with very low levels of PB1-F2 expression from swine-lineage viruses relative to a human isolate PB1-F2. Translational regulation of PB1-F2 expression was partially mapped to two independent regions within the PB1 mRNA, located downstream of the PB1-F2 start site. Our data suggest that encoding a full-length PB1-F2 ORF may not be predictive of PB1-F2 expression in infected cells for all influenza A viruses.
PMID:
23885074
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/23885074