Mechanism of interferon action: eIF-2 alpha phosphatase in interferon-treated mouse fibroblasts is double-stranded RNA independent.
The effect of double-stranded RNA on the dephosphorylation of purified, 32P-labeled eIF-2 was examined in cell-free extracts prepared from interferon-treated mouse L929 cells. Dephosphorylation of the alpha subunit of eIF-2 occurred at comparable rates in the presence and in the absence of reovirus dsRNA. By contrast, the beta subunit of eIF-2 was not dephosphorylated to any significant extent in either the presence or the absence of dsRNA. These results indicate that the enhanced phosphorylation of eIF-2 alpha observed in IFN-treated systems in the presence of double-stranded RNA (dsRNA) is indeed caused by an activation of a protein kinase rather than to an inhibition of a phosphoprotein phosphatase by the dsRNA.
D000818:Animals; D007370:Interferon Type I / Q000494:pharmacology*; D007739:L Cells / Q000187:drug effects* / Q000201:enzymology; D051379:Mice; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D010766:Phosphorylation; D012330:RNA, Double-Stranded / Q000494:pharmacology*
D007370:Interferon Type I; D012330:RNA, Double-Stranded; C019363:eIF-2 phosphatase; D010749:Phosphoprotein Phosphatases