title: Transcriptional regulation of endothelial nitric-oxide synthase by an interaction between casein kinase 2 and protein phosphatase 2A.
abstract: We previously demonstrated that lysophosphatidylcholine up-regulated endothelial nitric-oxide synthase promoter activity by increasing Sp1 binding via the action of protein serine/threonine phosphatase 2A (Cieslik, K., Zembowicz, A., Tang, J.-L., and Wu, K.K. (1998) J. Biol. Chem. 273, 14885-14890). To characterize the regulation of basal endothelial nitric-oxide synthase promoter activity and the signaling pathway through which lysophosphatidylcholine augments endothelial nitric-oxide synthase transcription, we used a casein kinase 2 inhibitor coupled with immunoprecipitation to demonstrate that basal Sp1 binding and endothelial nitric-oxide synthase promoter activity were controlled by casein kinase 2 complexed with protein serine/threonine phosphatase 2A. Casein kinase 2 catalyzed protein serine/threonine phosphatase 2A phosphorylation thereby inhibiting its activity. Lysophosphatidylcholine selectively activated p42/p44 mitogen-activated protein kinase. Purified extracellular regulated kinase 2 blocked casein kinase 2 activity and increased protein serine/threonine phosphatase 2A activity, resulting in an increased Sp1 binding and endothelial nitric-oxide synthase promoter activity. These results indicate that Sp1 binding to its cognate site on the endothelial nitric-oxide synthase promoter and its transactivation of endothelial nitric-oxide synthase is regulated by post-translational Sp1 phosphorylation and dephosphorylation through a dynamic interaction between casein kinase 2 and protein serine/threonine phosphatase 2A.
authors.affiliation: Vascular Biology Research Center, Division of Hematology, University of Texas-Houston Medical School, Houston, Texas 77030, USA.
authors.forename: K
authors.initials: K
authors.lastname: Cieslik
authors.forename: C M
authors.initials: CM
authors.lastname: Lee
authors.forename: J L
authors.initials: JL
authors.lastname: Tang
authors.forename: K K
authors.initials: KK
authors.lastname: Wu
mesh_terms: D047390:Casein Kinase II; D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured; D004004:Dichlororibofuranosylbenzimidazole / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006801:Humans; D008156:Luciferases / Q000378:metabolism; D008244:Lysophosphatidylcholines / Q000494:pharmacology; D048052:Mitogen-Activated Protein Kinase 3; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D052250:Nitric Oxide Synthase Type III; D019384:Nucleic Acid Synthesis Inhibitors / Q000494:pharmacology; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D054648:Protein Phosphatase 2; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D016329:Sp1 Transcription Factor / Q000378:metabolism; D013997:Time Factors; D014158:Transcription, Genetic
chemical_list: D004791:Enzyme Inhibitors; D005419:Flavonoids; D008244:Lysophosphatidylcholines; D019384:Nucleic Acid Synthesis Inhibitors; D016329:Sp1 Transcription Factor; D004004:Dichlororibofuranosylbenzimidazole; D008156:Luciferases; C496314:NOS3 protein, human; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III; D047390:Casein Kinase II; D017346:Protein Serine-Threonine Kinases; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D020929:Mitogen-Activated Protein Kinase Kinases; D010749:Phosphoprotein Phosphatases; D054648:Protein Phosphatase 2; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one