Specific protein phosphorylation in interferon-treated uninfected and virus-infected mouse L929 cells: enhancement by double-stranded RNA.
The enhanced phosphorylation of specific protein(s) observed in extracts from interferon-treated cells (in the presence of ATP and double-stranded [ds] RNA) was also seen in intact mouse L929 cells upon treatment with dsRNA, polyriboinosinic.polyribocytidylic acid [poly(rI.rC)] or reovirus dsRNA, using 32Pi as radiolabel. Labeling of a 65,000-dalton protein(s) with 32P was greatly increased in interferon-treated cells in the presence of added dsRNA, suggesting that the expression in vivo of the kinase activity involved is regulated by dsRNA. This was used as a test system to investigate whether the activity of interferon-induced enzyme(s) is stimulated following virus infection, possibly owing to the accumulation of dsRNA. No obvious increase in 32P-labeling of 65,000-dalton protein(s) was observed upon infection of interferon-treated cells with mengovirus or vesicular stomatitis virus. A basal level of 32P-labeling of the 65,000-dalton protein(s) was detected in interferon-treated cells in the absence of added dsRNA, indicating a basal level of expression of the kinase activity involved. The possible implications of these results are discussed.
D003609:Dactinomycin / Q000494:pharmacology; D007372:Interferons / Q000494:pharmacology*; D007739:L Cells; D008574:Mengovirus / Q000254:growth & development*; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism; D011506:Proteins / Q000378:metabolism*; D012313:RNA / Q000494:pharmacology / Q000502:physiology*; D012367:RNA, Viral / Q000502:physiology*; D012087:Reoviridae; D014721:Vesicular stomatitis Indiana virus / Q000254:growth & development*
D011506:Proteins; D012367:RNA, Viral; D003609:Dactinomycin; D012313:RNA; D007372:Interferons; D011494:Protein Kinases