Regulation of protein S-thiolation by glutaredoxin 5 in the yeast Saccharomyces cerevisiae.
The irreversible oxidation of cysteine residues can be prevented by protein S-thiolation, a process by which protein -SH groups form mixed disulfides with low molecular weight thiols such as glutathione. We report here that this protein modification is not a simple response to the cellular redox state, since different oxidants lead to different patterns of protein S-thiolation. SDS-polyacrylamide gel electrophoresis shows that glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is the major target for modification following treatment with hydroperoxides (hydrogen peroxide or tert-butylhydroperoxide), whereas this enzyme is unaffected following cellular exposure to the thiol oxidant diamide. Further evidence that protein S-thiolation is tightly regulated in response to oxidative stress is provided by the finding that the Tdh3 GAPDH isoenzyme, and not the Tdh2 isoenzyme, is S-thiolated following exposure to H(2)O(2) in vivo, whereas both GAPDH isoenzymes are S-thiolated when H(2)O(2) is added to cell-free extracts. This indicates that cellular factors are likely to be responsible for the difference in GAPDH S-thiolation observed in vivo rather than intrinsic structural differences between the GAPDH isoenzymes. To begin to search for factors that can regulate the S-thiolation process, we investigated the role of the glutaredoxin family of oxidoreductases. We provide the first evidence that protein dethiolation in vivo is regulated by a monothiol-glutaredoxin rather than the classical glutaredoxins, which contain two active site cysteine residues. In particular, glutaredoxin 5 is required for efficient dethiolation of the Tdh3 GAPDH isoenzyme.
Shenton
Daniel
D
Department of Biomolecular Sciences, University of Manchester Institute of Science and Technology, Manchester M60 1QD, United Kingdom.
Perrone
Gabriel
G
Quinn
Kathryn A
KA
Dawes
Ian W
IW
Grant
Chris M
CM
D002470:Cell Survival; D004591:Electrophoresis, Polyacrylamide Gel; D054477:Glutaredoxins; D005978:Glutathione / Q000378:metabolism; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000494:pharmacology; D016877:Oxidants / Q000494:pharmacology; D010084:Oxidation-Reduction; D010088:Oxidoreductases; D010100:Oxygen / Q000378:metabolism; D011485:Protein Binding; D020033:Protein Isoforms; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D013438:Sulfhydryl Compounds / Q000378:metabolism*; D013997:Time Factors
D054477:Glutaredoxins; D016877:Oxidants; D020033:Protein Isoforms; D011506:Proteins; D013438:Sulfhydryl Compounds; D006861:Hydrogen Peroxide; D010088:Oxidoreductases; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D005978:Glutathione; D010100:Oxygen