title: S-glutathiolation of Ras mediates redox-sensitive signaling by angiotensin II in vascular smooth muscle cells.
abstract: Angiotensin II (AII) increases production of reactive oxygen species from NAD(P)H oxidase, a response that contributes to vascular hypertrophy. Here we show in cultured vascular smooth muscle cells that S-glutathiolation of the redox-sensitive Cys(118) on the small GTPase, Ras, plays a critical role in AII-induced hypertrophic signaling. AII simultaneously increased the Ras activity and the S-glutathiolation of Ras (GSS-Ras) detected by biotin-labeled GSH or mass spectrometry. Both the increase in activity and GSS-Ras was labile under reducing conditions, suggesting the essential nature of this thiol modification to Ras activation. Overexpression of catalase, a dominant-negative p47(phox), or glutaredoxin-1 decreased GSS-Ras, Ras activation, p38, and Akt phosphorylation and the induction of protein synthesis by AII. Furthermore, expression of a Cys(118) mutant Ras decreased AII-mediated p38 and Akt phosphorylation as well as protein synthesis. These results show that H(2)O(2) from NAD(P)H oxidase forms GSS-Ras on Cys(118) and increases its activity leading to p38 and Akt phosphorylation, which contributes to the induction of protein synthesis. This study suggests that GSS-Ras is a redox-sensitive signaling switch that participates in the cellular response to AII.
authors.affiliation: Vascular Biology Unit, Whitaker Cardiovascular Institute, Boston University Medical Center, Boston, Massachusetts 02118, USA. tadachi@bumc.bu.edu
authors.forename: Takeshi
authors.initials: T
authors.lastname: Adachi
authors.forename: David R
authors.initials: DR
authors.lastname: Pimentel
authors.forename: Tyler
authors.initials: T
authors.lastname: Heibeck
authors.forename: Xiuyun
authors.initials: X
authors.lastname: Hou
authors.forename: Yong J
authors.initials: YJ
authors.lastname: Lee
authors.forename: Bingbing
authors.initials: B
authors.lastname: Jiang
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Ido
authors.forename: Richard A
authors.initials: RA
authors.lastname: Cohen
mesh_terms: D000804:Angiotensin II / Q000378:metabolism*; D000818:Animals; D002478:Cells, Cultured; D004789:Enzyme Activation; D066246:ErbB Receptors / Q000378:metabolism; D054477:Glutaredoxins; D005978:Glutathione / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000166:cytology*; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000378:metabolism*; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D019255:NADPH Oxidases; D016877:Oxidants / Q000378:metabolism; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D048051:p38 Mitogen-Activated Protein Kinases; D018631:ras Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: C516007:Glrx protein, rat; C516010:Glrx2 protein, rat; D054477:Glutaredoxins; D016877:Oxidants; D011518:Proto-Oncogene Proteins; D017382:Reactive Oxygen Species; D000804:Angiotensin II; D006861:Hydrogen Peroxide; D010088:Oxidoreductases; D009247:NADH, NADPH Oxidoreductases; D019255:NADPH Oxidases; D066246:ErbB Receptors; C494918:AKT1 protein, human; C494920:Akt1 protein, rat; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D018631:ras Proteins; D005978:Glutathione