Expression, subcellular localization, and antioxidant role of mammalian methionine sulfoxide reductases in Saccharomyces cerevisiae.
Despite the growing body of evidence suggesting a role for MsrA in antioxidant defense, little is currently known regarding the function of MsrB in cellular protection against oxidative stress. In this study, we overexpressed the mammalian MsrB and MsrA genes in Saccharomyces cerevisiae and assessed their subcellular localization and antioxidant functions. We found that the mitochondrial MsrB3 protein (MsrB3B) was localized to the cytosol, but not to the mitochondria, of the yeast cells. The mitochondrial MsrB2 protein was detected in the mitochondria and, to a lesser extent, the cytosol of the yeast cells. In this study, we report the first evidence that MsrB3 overexpression in yeast cells protected them against H(2)O(2)-mediated cell death. Additionally, MsrB2 overexpression also provided yeast cells with resistance to oxidative stress, as did MsrA overexpression. Our results show that mammalian MsrB and MsrA proteins perform crucial functions in protection against oxidative stress in lower eukaryotic yeast cells.
Kwak
Geun-Hee
GH
Department of Biochemistry and Molecular Biology, Aging-associated Vascular Disease Research Center, Yeungnam University College of Medicine, Daegu 705-717, Korea.
Kim
Jae-Ryong
JR
Kim
Hwa-Young
HY
D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D006801:Humans; D051150:Methionine Sulfoxide Reductases; D051379:Mice; D008840:Microfilament Proteins; D018384:Oxidative Stress; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000201:enzymology* / Q000235:genetics
D000975:Antioxidants; D008840:Microfilament Proteins; D010088:Oxidoreductases; D051150:Methionine Sulfoxide Reductases; C520510:Msrb2 protein, mouse; C027219:methionine sulfoxide reductase