Selective effects of TPA and IL-1 on protein phosphorylation in murine thymocytes.
Protein kinase C activity was demonstrated in murine thymocytes and the effects of TPA and IL-1 on this enzyme were studied. TPA, but not IL-1, could substitute for diacylglycerol in protein kinase C activation. Although TPA and IL-1 are both potent comitogens for murine thymocytes they markedly differ in their effects on protein phosphorylation and protein kinase C activation. Treatment of intact thymocytes with TPA resulted in a marked increase in the phosphorylation of an endogenous protein with Mr approximately 44,000. Enhanced phosphorylation of this protein was also observed when protein kinase C was activated in thymocyte extracts. In contrast to TPA, IL-1 neither induced phosphorylation of the 44,000-Da protein nor activated protein kinase C. The data suggests that protein kinase C does not mediate the comitogenic effect of IL-1 in murine thymocytes.
D000818:Animals; D002746:Chlorpromazine / Q000494:pharmacology; D004075:Diglycerides / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D007375:Interleukin-1 / Q000494:pharmacology*; D037102:Lectins; D008012:Lidocaine / Q000494:pharmacology; D051379:Mice; D008970:Molecular Weight; D019887:Peanut Agglutinin; D010704:Phorbols / Q000494:pharmacology*; D010750:Phosphoproteins / Q000378:metabolism*; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism; D013601:T-Lymphocytes / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D013950:Thymus Gland / Q000166:cytology
D004075:Diglycerides; D007375:Interleukin-1; D037102:Lectins; D019887:Peanut Agglutinin; D010704:Phorbols; D010750:Phosphoproteins; D008012:Lidocaine; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate; D002746:Chlorpromazine