title: Thiol redox proteomics identifies differential targets of cytosolic and mitochondrial glutaredoxin-2 isoforms in Saccharomyces cerevisiae. Reversible S-glutathionylation of DHBP synthase (RIB3).
abstract: Yeast Grx2 plays a role in the antioxidant glutathione linked defense acting on the redox status of protein cysteines, but the exact action or its specificity is not known. Moreover, it localizes in cytosol and mitochondria where it can exert different functions. To search for functions of Grx2 we determined the differential "Thiolic Redox Proteome" of control and peroxide-treated yeast mutant cells lacking the gene for Grx2 or expressing Grx2 exclusively in the mitochondria. Forty-two proteins have been identified that have alternative redox oxidation states as a consequence of Grx2 absence from the cell or expression in the mitochondria and absence from the cytosol. The precise cysteine residues affected have been mapped for each protein. One target protein, Rib3p, which has as yet an undefined function in respiration, was confirmed to have its Cys56 reversibly S-glutathionylated in vitro in a Grx2p dependent process. Grx2-dependent redox changes in key enzymes of glutamate consuming amino acid biosynthetic pathways could favor glutathione biosynthesis. Other target proteins are involved in membrane fusion, cell wall structure and ribosome assembly, but others are of unknown function. These results provide clues on the metabolic hot spots of redox regulatory mechanisms.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Córdoba and Córdoba Maimónides Institute for Biomedical Research, IMIBIC, Córdoba, Spain.
authors.forename: B
authors.initials: B
authors.lastname: McDonagh
authors.forename: R
authors.initials: R
authors.lastname: Requejo
authors.forename: C A
authors.initials: CA
authors.lastname: Fuentes-Almagro
authors.forename: S
authors.initials: S
authors.lastname: Ogueta
authors.forename: J A
authors.initials: JA
authors.lastname: Bárcena
authors.forename: C A
authors.initials: CA
authors.lastname: Padilla
mesh_terms: D000603:Amino Acids, Sulfur / Q000032:analysis / Q000378:metabolism*; D003600:Cytosol / Q000201:enzymology / Q000378:metabolism; D054477:Glutaredoxins / Q000378:metabolism* / Q000502:physiology; D005978:Glutathione / Q000378:metabolism; D019751:Intramolecular Transferases / Q000378:metabolism*; D007527:Isoenzymes / Q000378:metabolism; D008928:Mitochondria / Q000201:enzymology / Q000378:metabolism; D008954:Models, Biological; D010084:Oxidation-Reduction; D010449:Peptide Mapping / Q000379:methods; D011499:Protein Processing, Post-Translational; D020543:Proteome / Q000032:analysis / Q000378:metabolism; D040901:Proteomics / Q000379:methods*; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000032:analysis / Q000378:metabolism* / Q000502:physiology; D013379:Substrate Specificity; D013438:Sulfhydryl Compounds / Q000378:metabolism*
chemical_list: D000603:Amino Acids, Sulfur; D054477:Glutaredoxins; C527885:Grx2 protein, S cerevisiae; D007527:Isoenzymes; D020543:Proteome; D029701:Saccharomyces cerevisiae Proteins; D013438:Sulfhydryl Compounds; D019751:Intramolecular Transferases; C066493:L-3,4-dihydroxy-2-butanone-4-phosphate synthase; D005978:Glutathione