title: West Nile virus infection does not induce PKR activation in rodent cells.
abstract: dsRNA-activated protein kinase (PKR) is activated by viral dsRNAs and phosphorylates eIF2a reducing translation of host and viral mRNA. Although infection with a chimeric West Nile virus (WNV) efficiently induced PKR and eIF2a phosphorylation, infections with natural lineage 1 or 2 strains did not. Investigation of the mechanism of suppression showed that among the cellular PKR inhibitor proteins tested, only Nck, known to interact with inactive PKR, colocalized and co-immunoprecipitated with PKR in WNV-infected cells and PKR phosphorylation did not increase in infected Nck1,2-/- cells. Several WNV stem-loop RNAs efficiently activated PKR in vitro but not in infected cells. WNV infection did not interfere with intracellular PKR activation by poly(I:C) and similar virus yields were produced by control and PKR-/- cells. The results indicate that PKR phosphorylation is not actively suppressed in WNV-infected cells but that PKR is not activated by the viral dsRNA in infected cells.
authors: Department of Biology, Georgia State University, Atlanta, GA 30303, USA.
authors: H
authors: H
authors: Elbahesh
authors: S V
authors: SV
authors: Scherbik
authors: M A
authors: MA
authors: Brinton
mesh_terms: D000818:Animals; D002460:Cell Line; D006224:Cricetinae; D004789:Enzyme Activation; D015852:Eukaryotic Initiation Factor-2 / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D010766:Phosphorylation; D012376:Rodent Diseases / Q000201:enzymology* / Q000235:genetics / Q000821:virology; D012377:Rodentia / Q000235:genetics / Q000378:metabolism / Q000821:virology*; D014901:West Nile Fever / Q000201:enzymology / Q000235:genetics / Q000662:veterinary* / Q000821:virology; D014902:West Nile virus / Q000235:genetics / Q000502:physiology*; D019892:eIF-2 Kinase / Q000235:genetics / Q000378:metabolism*
chemical_list: D015852:Eukaryotic Initiation Factor-2; D019892:eIF-2 Kinase