The polypyrimidine tract binding protein is required for efficient picornavirus gene expression and propagation.

Imagen de Mariano Garcia-Blanco
TítuloThe polypyrimidine tract binding protein is required for efficient picornavirus gene expression and propagation.
Publication TypeJournal Article
Year of Publication2005
AutoresFlorez, PM, Sessions, OM, Wagner, EJ, Gromeier, M, García-Blanco, MA
JournalJ Virol
Volume79
Issue10
Pagination6172-9
Date Published2005 May
ISSN0022-538X
Palabras claveDNA-Binding Proteins, Encephalomyocarditis virus, Gene Expression Regulation, Viral, Genes, Viral, HeLa Cells, Humans, Picornaviridae, Picornaviridae Infections, Poliovirus, Polypyrimidine Tract-Binding Protein, RNA, Small Interfering, Virus Replication
Abstract

Mammalian host factors required for efficient viral gene expression and propagation have been often recalcitrant to genetic analysis. A case in point is the function of cellular factors that trans-activate internal ribosomal entry site (IRES)-driven translation, which is operative in many positive-stranded RNA viruses, including all picornaviruses. These IRES trans-acting factors have been elegantly studied in vitro, but their in vivo importance for viral gene expression and propagation has not been widely confirmed experimentally. Here we use RNA interference to deplete mammalian cells of one such factor, the polypyrimidine tract binding protein, and test its requirement in picornavirus gene expression and propagation. Depletion of the polypyrimidine tract binding protein resulted in a marked delay of particle propagation and significantly decreased synthesis and accumulation of viral proteins of poliovirus and encephalomyocarditis virus. These effects could be partially restored by expression of an RNA interference-resistant exogenous polypyrimidine tract binding protein. These data indicate a critical role for the polypyrimidine tract binding protein in picornavirus gene expression and strongly suggest a requirement for efficient IRES-dependent translation.

DOI10.1128/JVI.79.10.6172-6179.2005
Alternate JournalJ. Virol.
PubMed ID15858002