Influenza A virus PB1-F2 protein expression is regulated in a strain-specific manner by sequences located downstream of the PB1-F2 initiation codon.
J Virol
; 87(19): 10687-99, 2013 Oct.
Article
em En
| MEDLINE
| ID: mdl-23885074
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 collected primarily 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 carry 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 in 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 carrying a full-length PB1-F2 ORF may not be predictive of PB1-F2 expression in infected cells for all influenza A viruses.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Virais
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Replicação Viral
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Regulação Viral da Expressão Gênica
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Infecções por Orthomyxoviridae
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Códon de Iniciação
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Vírus da Influenza A Subtipo H1N1
Tipo de estudo:
Prognostic_studies
Limite:
Animals
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Humans
Idioma:
En
Revista:
J Virol
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Estados Unidos