Interferon-induced antiviral RNA-binding protein that specifically binds single-stranded RNA bearing a 5'-triphosphate group (PPP-RNA), thereby acting as a sensor of viral single-stranded RNAs and inhibiting expression of viral messenger RNAs. Single-stranded PPP-RNAs, which lack 2'-O-methylation of the 5' cap and bear a 5'-triphosphate group instead, are specific from viruses, providing a molecular signature to distinguish between self and non-self mRNAs by the host during viral infection. Directly binds PPP-RNA in a non-sequence-specific manner. Viruses evolved several ways to evade this restriction system such as encoding their own 2'-O-methylase for their mRNAs or by stealing host cap containing the 2'-O-methylation (cap snatching mechanism). Exhibits antiviral activity against several viruses including human papilloma and hepatitis C viruses.

• GO:0071360 : cellular response to exogenous dsRNA
• GO:0051607 : defense response to virus
• GO:0019060 : intracellular transport of viral proteins in host cell
• GO:0050689 : negative regulation of defense response to virus by host
• GO:0051097 : negative regulation of helicase activity
• GO:0032091 : negative regulation of protein binding
• GO:0045071 : negative regulation of viral genome replication
• GO:0045070 : positive regulation of viral genome replication
• GO:0009615 : response to virus
• GO:0060337 : type I interferon-mediated signaling pathway

Source: The Gene Ontology Consortium. Gene ontology: tool for the unification of biology. Nat. Genet.. May 2000;25(1):25-9.
World Wide Web URL: http://www.geneontology.org/

Source: Online Mendelian Inheritance in Man, OMIM®. McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University (Baltimore, MD), May, 2012.
World Wide Web URL: http://omim.org/