Basal and phorbol-ester-stimulated turnover of phosphatidylcholine in HeLa cells involve different pathways.
HeLa cells prelabelled with [3H]lysoplatelet-activating factor (lyso-PAF) accumulated phosphatidic acid (PtdOH) when incubated in the presence of either propranolol (an inhibitor of PtdOH phosphohydrolase) or phorbol ester. In the presence of ethanol, phorbol ester but not propranolol stimulated the accumulation of phosphatidylethanol, an index of phospholipase D activity. Incubation of cells with [3H]lyso-PAF led to a rapid accumulation of label in diacylglycerol (DG) followed by a delayed accumulation in PtdOH. It is concluded that propranolol-induced PtdOH accumulation is derived from DG by DG kinase and does not involve phospholipase D.
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School of Biological Sciences, Flinders University, Adelaide, South Australia, Australia.
Edwards
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Murray
A W
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D002462:Cell Membrane / Q000378:metabolism; D019852:Diacylglycerol Kinase; D004075:Diglycerides / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D010712:Phosphatidic Acids / Q000378:metabolism; D010713:Phosphatidylcholines / Q000378:metabolism*; D010739:Phospholipase D / Q000378:metabolism; D010770:Phosphotransferases / Q000378:metabolism; D010972:Platelet Activating Factor / Q000031:analogs & derivatives / Q000378:metabolism; D013268:Stimulation, Chemical; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*; D014316:Tritium; D010738:Type C Phospholipases / Q000378:metabolism
D004075:Diglycerides; C029271:O-deacetyl platelet activating factor; D010712:Phosphatidic Acids; D010713:Phosphatidylcholines; D010972:Platelet Activating Factor; D014316:Tritium; D010770:Phosphotransferases; D019852:Diacylglycerol Kinase; D010738:Type C Phospholipases; D010739:Phospholipase D; D013755:Tetradecanoylphorbol Acetate