title: Dynamic activation of endothelial nitric oxide synthase by Hsp90.
abstract: Heat-shock protein 90 (Hsp90) coordinates the trafficking and regulation of diverse signalling proteins, but its precise role in regulating specific cellular targets is not known. Here we show that Hsp90 associates with endothelial nitric oxide synthase (eNOS) and is rapidly recruited to the eNOS complex by agonists that stimulate production of nitric oxide, namely vascular endothelial growth factor, histamine and fluid shear stress. Moreover, the binding of Hsp90 to eNOS enhances the activation of eNOS. Inhibition of signalling through Hsp90 attenuates both agonist-stimulated production of nitric oxide and endothelium-dependent relaxation of isolated blood vessels. Our results indicate that Hsp90 facilitates signalling mediated by growth-factor, G-protein and mechanotransduction pathways that lead to the activation of eNOS. These observations indicate that in addition to its role as a molecular chaperone involved in protein folding and maturation, Hsp90 may also be recruited to cellular targets depending on the activation state of the cell.
authors.affiliation: Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06536, USA.
authors.forename: G
authors.initials: G
authors.lastname: García-Cardeña
authors.forename: R
authors.initials: R
authors.lastname: Fan
authors.forename: V
authors.initials: V
authors.lastname: Shah
authors.forename: R
authors.initials: R
authors.lastname: Sorrentino
authors.forename: G
authors.initials: G
authors.lastname: Cirino
authors.forename: A
authors.initials: A
authors.lastname: Papapetropoulos
authors.forename: W C
authors.initials: WC
authors.lastname: Sessa
mesh_terms: D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D001011:Aorta; D016227:Benzoquinones; D019556:COS Cells; D002417:Cattle; D002460:Cell Line; D016228:Endothelial Growth Factors / Q000378:metabolism; D004730:Endothelium, Vascular / Q000201:enzymology*; D004789:Enzyme Activation; D018841:HSP90 Heat-Shock Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D006632:Histamine / Q000378:metabolism; D006801:Humans; D047029:Lactams, Macrocyclic; D008222:Lymphokines / Q000378:metabolism; D009126:Muscle Relaxation / Q000187:drug effects; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D011233:Precipitin Tests; D011809:Quinones / Q000494:pharmacology; D051381:Rats; D015398:Signal Transduction; D013314:Stress, Mechanical; D014162:Transfection; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
chemical_list: D000903:Antibiotics, Antineoplastic; D016227:Benzoquinones; D016228:Endothelial Growth Factors; D018841:HSP90 Heat-Shock Proteins; D047029:Lactams, Macrocyclic; D008222:Lymphokines; D011809:Quinones; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D009569:Nitric Oxide; D006632:Histamine; D019001:Nitric Oxide Synthase; C001277:geldanamycin