title: Direct activation of purified protein kinase C by unsaturated fatty acids (oleate and arachidonate) in the absence of phospholipids and Ca2+.
abstract: Unsaturated fatty acids (oleic acid and arachidonic acid) activate purified protein kinase C independently of phospholipid and Ca2+. Oleic acid activation of protein kinase C is as effective as phosphatidylserine and Ca2+. Ka values for oleic acid and arachidonic acid are 50 and 53 microM, respectively. In contrast to the cis fatty acids, a trans form (elaidic acid) or a saturated fatty acid (stearic acid) has little or no effect on protein kinase C activation. If cis fatty acid liberation is physiologically important, this suggests that another mechanism may exist for protein kinase C activation, in addition to phospholipase C/phosphatidylinositol turnover signaling, possibly via the liberation of cis fatty acids by the Ca2+-dependent phospholipase A2 system.
mesh_terms: D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000494:pharmacology*; D001921:Brain / Q000201:enzymology*; D002118:Calcium / Q000494:pharmacology*; D004789:Enzyme Activation; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology*; D007700:Kinetics; D019301:Oleic Acid; D009829:Oleic Acids / Q000494:pharmacology*; D010743:Phospholipids / Q000494:pharmacology*; D011493:Protein Kinase C / Q000302:isolation & purification / Q000378:metabolism*; D051381:Rats; D013329:Structure-Activity Relationship
chemical_list: D001095:Arachidonic Acids; D005231:Fatty Acids, Unsaturated; D009829:Oleic Acids; D010743:Phospholipids; D016718:Arachidonic Acid; D019301:Oleic Acid; D011493:Protein Kinase C; D002118:Calcium