Journal article
YBP1 and Its Homologue YBP2/YBH1 Influence Oxidative-Stress Tolerance by Nonidentical Mechanisms in Saccharomyces cerevisiae
Eukaryotic cell, Vol.3(2), pp.318-330
04/2004
DOI: 10.1128/EC.3.2.318-330.2004
PMCID: PMC387662
PMID: 15075262
Abstract
ABSTRACT
In the yeast
Saccharomyces cerevisiae
, the transcription factor Yap1p is a central determinant of resistance to oxidative stress. Previous work has demonstrated that Yap1p is recruited from the cytoplasm to the nucleus upon exposure to the oxidants diamide and H
2
O
2
in a process that requires the transient covalent linkage of the glutathione peroxidase Gpx3p to Yap1p. Genetic and biochemical analyses indicate that while both oxidants trigger nuclear accumulation of Yap1p, the function and regulation of this transcription factor is different under these two different oxidative stresses. Ybp1p (Yap1p-binding protein) has recently been demonstrated to be required for Yap1p-mediated H
2
O
2
resistance but not diamide resistance. A Ybp1p homologous protein (Ybh1p/Ybp2p) was also detected in the
S. cerevisiae
genome. Here we compare the actions of these two closely related proteins and provide evidence that while both factors influence H
2
O
2
tolerance, they do so by nonidentical mechanisms. A double mutant strain lacking both
YBP1
and
YBH1
genes is more sensitive to H
2
O
2
and more defective in activation of Yap1p-dependent gene expression than either single mutant. Ybp1p has a more pronounced effect on these phenotypes than does Ybh1p. Protein-protein interactions between Yap1p and Ybp1p could be detected by either the yeast two-hybrid or coimmunoprecipitation approach while neither technique could demonstrate Yap1p-Ybh1p interactions. Overexpression experiments indicated that high levels of Ybh1p but not Ybp1p could bypass the H
2
O
2
hypersensitivity of a
gpx3
Δ strain. Together, these data argue that these two homologous proteins act as parallel positive regulators of H
2
O
2
tolerance.
Details
- Title: Subtitle
- YBP1 and Its Homologue YBP2/YBH1 Influence Oxidative-Stress Tolerance by Nonidentical Mechanisms in Saccharomyces cerevisiae
- Creators
- Kailash Gulshan - University of IowaSherry A. Rovinsky - University of IowaW. Scott Moye-Rowley - University of Iowa
- Resource Type
- Journal article
- Publication Details
- Eukaryotic cell, Vol.3(2), pp.318-330
- DOI
- 10.1128/EC.3.2.318-330.2004
- PMID
- 15075262
- PMCID
- PMC387662
- NLM abbreviation
- Eukaryot Cell
- ISSN
- 1535-9778
- eISSN
- 1535-9786
- Publisher
- American Society for Microbiology
- Language
- English
- Date published
- 04/2004
- Academic Unit
- Molecular Physiology and Biophysics; Internal Medicine
- Record Identifier
- 9984297614802771
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