title: Okadaic acid strongly increases gene transcription, mRNA and protein level for the urokinase receptor in human A549 cells.
abstract: The specific phosphatase inhibitor, okadaic acid, increases the level of mRNA for the receptor for urokinase-type plasminogen activator (u-PAR) in 8 out of 13 human cell lines. The strongest increase (90-fold) was observed in A549 lung carcinoma cells, in which it was partly traced back to an increased transcription of the u-PAR gene. There was a parallel but less pronounced increase in the u-PAR protein level. These findings indicate that u-PAR gene transcription is regulated by one or more factors that are constitutively phosphorylated and are dephosphorylated by okadaic acid-sensitive phosphatases. A lack of additivity of u-PAR induction by okadaic acid and by the protein kinase C activator, PMA, in the A549 cells suggests that the regulatory factors affected by okadaic acid are phosphorylated by protein kinase C.
authors.affiliation: Finsen Laboratory, Rigshospitalet, Copenhagen, Denmark.
authors.forename: L R
authors.initials: LR
authors.lastname: Lund
authors.forename: K
authors.initials: K
authors.lastname: Danø
mesh_terms: D015152:Blotting, Northern; D002460:Cell Line; D004988:Ethers, Cyclic / Q000494:pharmacology*; D005786:Gene Expression Regulation; D006801:Humans; D019319:Okadaic Acid; D009928:Organ Specificity / Q000235:genetics; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors*; D010960:Plasminogen Activators / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics* / Q000378:metabolism; D055293:Receptors, Urokinase Plasminogen Activator; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014158:Transcription, Genetic / Q000187:drug effects*; D016212:Transforming Growth Factor beta / Q000494:pharmacology; D014407:Tumor Cells, Cultured; D014568:Urokinase-Type Plasminogen Activator / Q000378:metabolism*
chemical_list: D004988:Ethers, Cyclic; C524898:PLAUR protein, human; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D055293:Receptors, Urokinase Plasminogen Activator; D016212:Transforming Growth Factor beta; D019319:Okadaic Acid; D010749:Phosphoprotein Phosphatases; D010960:Plasminogen Activators; D014568:Urokinase-Type Plasminogen Activator; D013755:Tetradecanoylphorbol Acetate