Adenosine 3',5'-monophosphate-dependent protein kinase(s) in diploid and SV40 transformed human fibroblasts.
Cyclic AMP-dependent protein kinases (EC 2.7.1.37; ATP:protein phosphotransferase) in the human diploid fibroblast WI-38 and an SV40-transformant WI-38-VA13-2RA (VA13) have been compared on the basis of their concentrations in cells, isoenzyme composition and susceptibility to hormonal activation. In high population density cultures, total soluble cyclic AMP-dependent kinase activities measured with histone were essentially the same in WI-38 and VA13. Two soluble protein kinase forms separated by chromatography on DEAE-cellulose were present in both cell lines. The concentration of cyclic AMP required for half-maximal activation of both enzyme forms was 10-30 nM. Overall kinase stimulation was greater for the Peak I enzymes. Kinase activation induced in the presence of 0.5 M KCl was more rapid and complete for the Peak I enzymes. Under conditions which elevated the concentration of cyclic AMP in WI-38 and VA13 cells the activities of the soluble histone kinases were increased. Incubation of the cells with either of 5.7 micronM prostaglandin E1 or 1 micronM isopropylnorepinephrine induced complete activation of the cyclic AMP-dependent histone kinases within 5 min and maintained the effect for 20 min. When intracellular cyclic AMP levels were raised by prostaglandin E1, activation of glycogen phosphorylase (assayed-AMP) suggested that this enzyme cascade involving cyclic AMP-dependent protein kinase(s) was intact and responsive in both cell lines.
D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D000242:Cyclic AMP / Q000494:pharmacology*; D004171:Diploidy; D004789:Enzyme Activation; D006801:Humans; D007700:Kinetics; D011458:Prostaglandins E / Q000494:pharmacology; D006656:Protamine Kinase / Q000378:metabolism; D011494:Protein Kinases / Q000302:isolation & purification / Q000378:metabolism*; D013539:Simian virus 40
D011458:Prostaglandins E; D000242:Cyclic AMP; D011494:Protein Kinases; D006656:Protamine Kinase