Nitric oxide inhibits c-Jun DNA binding by specifically targeted S-glutathionylation.
This study addresses potential molecular mechanisms underlying the inhibition of the transcription factor c-Jun by nitric oxide. We show that in the presence of the physiological sulfhydryl glutathione nitric oxide modifies the two cysteine residues contained in the DNA binding module of c-Jun in a selective and distinct way. Although nitric oxide induced the formation of an intermolecular disulfide bridge between cysteine residues in the leucine zipper site of c-Jun monomers, this same radical directed the covalent incorporation of stoichiometric amounts of glutathione to a single conserved cysteine residue in the DNA-binding site of the protein. We found that covalent dimerization of c-Jun apparently did not affect its DNA binding activity, whereas the formation of a mixed disulfide with glutathione correlated well with the inhibition of transcription factor binding to DNA. Furthermore, we provide experimental evidence that nitric oxide-induced S-glutathionylation and inhibition of c-Jun involves the formation of S-nitrosoglutathione. In conclusion, our results support the reversible formation of a mixed disulfide between glutathione and c-Jun as a potential mechanism by which nitrosative stress may be transduced into a functional response at the level of transcription.
Klatt
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Departamento de Estructura y Función de Proteínas, Centro de Investigaciones Biológicas, Instituto Reina Sofía de Investigaciones Nefrológicas, Consejo Superior de Investigaciones Científicas, Velázquez 144, E-28006 Madrid,Spain.
Molina
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EP
Lamas
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D003545:Cysteine / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000737:chemistry*; D019281:Dimerization; D004220:Disulfides / Q000737:chemistry; D005978:Glutathione / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D019803:Glutathione Disulfide / Q000737:chemistry; D006801:Humans; D009569:Nitric Oxide / Q000494:pharmacology*; D009603:Nitroso Compounds / Q000737:chemistry / Q000494:pharmacology; D011485:Protein Binding / Q000187:drug effects; D016755:Proto-Oncogene Proteins c-jun / Q000737:chemistry* / Q000235:genetics; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics; D026422:S-Nitrosoglutathione; D014157:Transcription Factors / Q000235:genetics
D004268:DNA-Binding Proteins; D004220:Disulfides; D009603:Nitroso Compounds; D016755:Proto-Oncogene Proteins c-jun; D011994:Recombinant Proteins; D014157:Transcription Factors; D009569:Nitric Oxide; D026422:S-Nitrosoglutathione; D005978:Glutathione; D003545:Cysteine; D019803:Glutathione Disulfide