Inhibition of 12-O-tetradecanoylphorbol-13-acetate induction of c-fos mRNA by the protein kinase A inhibitor N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinoline sulfonamide.
The tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) can induce expression of many immediate-early genes, such as c-fos and c-jun. In this study, TPA increased c-fos mRNA, cellular cyclic AMP, and protein kinase A (PKA) activity in the first 30 min with similar inductive time courses. Treatment of NIH 3T3 cells with N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinoline sulfonamide (H-89), a PKA specific inhibitor, suppressed TPA induction of PKA activity and c-fos mRNA in a concentration-dependent manner, but did not inhibit serum-induced transcription. H-89 did not inhibit TPA and serum induction of c-jun mRNA. H-89 interfered with TPA-stimulated serum-responsive element-binding activity in a concentration-dependent manner, but did not inhibit TPA-induced mitogen-activated protein kinase 1/2 activity or Elk-1 phosphorylation. TPA stimulation of a c-fos promoter reporter construct was inhibited by overexpression of the dominant negative regulatory protein of PKA. In deletion studies, the H-89 inhibitory element was found to be localized between -563 and -379 in the c-fos promoter region. These results suggest that H-89 will be very useful for investigating the molecular mechanism of TPA induction of c-fos.
Huang
Y T
YT
Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan.
Lin
J K
JK
Lee
M T
MT
D016475:3T3 Cells; D000818:Animals; D002273:Carcinogens / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D004347:Drug Interactions; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D007546:Isoquinolines / Q000494:pharmacology*; D051379:Mice; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis* / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D013449:Sulfonamides; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014158:Transcription, Genetic / Q000187:drug effects
D002273:Carcinogens; D004791:Enzyme Inhibitors; D007546:Isoquinolines; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger; D013449:Sulfonamides; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; C063509:N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide; D013755:Tetradecanoylphorbol Acetate