title: The protein phosphatase inhibitor, okadaic acid, potentiates the stimulatory effect of phorbol ester on phosphatidylcholine synthesis, but not on phospholipid hydrolysis, in fibroblasts.
abstract: The potent protein phosphatase inhibitor, okadaic acid, was used to determine the possible role of protein phosphorylation reaction(s) in phorbol ester-induced synthesis and hydrolysis of phosphatidylcholine (PtdCho) in NIH 3T3 fibroblasts. Okadaic acid (2 microM) was found to enhance the stimulatory effects of lower concentrations (2.5-25 nM) of phorbol 12-myristate 13-acetate (PMA) on PtdCho synthesis, but not on PtdCho hydrolysis, after treatments for 30-60 min. These data support a view that in fibroblasts PMA stimulates only PtdCho synthesis, and not PtdCho hydrolysis, by a protein phosphorylation-dependent mechanism.
authors.affiliation: Hormel Institute, University of Minnesota, Austin 55912.
authors.forename: Z
authors.initials: Z
authors.lastname: Kiss
mesh_terms: D016475:3T3 Cells; D000818:Animals; D002794:Choline / Q000378:metabolism; D004357:Drug Synergism; D004988:Ethers, Cyclic / Q000494:pharmacology*; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism*; D006868:Hydrolysis; D051379:Mice; D019319:Okadaic Acid; D010713:Phosphatidylcholines / Q000096:biosynthesis*; D010743:Phospholipids / Q000378:metabolism*; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D004988:Ethers, Cyclic; D010713:Phosphatidylcholines; D010743:Phospholipids; D019319:Okadaic Acid; D010749:Phosphoprotein Phosphatases; D002794:Choline; D013755:Tetradecanoylphorbol Acetate