title: Functional interaction of endothelial nitric oxide synthase with a voltage-dependent anion channel.
abstract: Endothelium-derived nitric oxide (NO) is an important regulator of vascular function. NO is produced by endothelial NO synthase (eNOS) whose function is modulated, in part, by specific protein interactions. By coimmunoprecipitation experiments followed by MS analyses, we identified a human voltage-dependent anion/cation channel or porin as a binding partner of eNOS. The interaction between porin and eNOS was demonstrated by coimmunoprecipitation studies in nontransfected human endothelial cells and Cos-7 cells transiently transfected with eNOS and porin cDNAs. In vitro binding studies with glutathione S-transferase-porin indicated that porin binds directly to eNOS and that this interaction augmented eNOS activity. The calcium ionophore, and bradykinin, which are known to activate eNOS, markedly increased porin-eNOS interaction, suggesting a potential role of intracellular Ca(2+) in mediating this interaction. Theses results indicate that the interaction between a voltage-dependent membrane channel and eNOS may be important for regulating eNOS activity.
authors.affiliation: Cardiovascular Division, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Jianxin
authors.initials: J
authors.lastname: Sun
authors.forename: James K
authors.initials: JK
authors.lastname: Liao
mesh_terms: D000818:Animals; D000838:Anions; D001011:Aorta / Q000473:pathology; D015153:Blotting, Western; D019556:COS Cells; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D002417:Cattle; D002460:Cell Line; D002845:Chromatography; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D015151:Immunoblotting; D007476:Ionophores / Q000494:pharmacology; D013058:Mass Spectrometry; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D052250:Nitric Oxide Synthase Type III; D018272:Porins / Q000737:chemistry / Q000378:metabolism*; D011233:Precipitin Tests; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015398:Signal Transduction; D014162:Transfection
chemical_list: D000838:Anions; D007476:Ionophores; D018272:Porins; D011993:Recombinant Fusion Proteins; D009569:Nitric Oxide; D000001:Calcimycin; C496314:NOS3 protein, human; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III; D005982:Glutathione Transferase; D002118:Calcium