TY - JOUR
T1 - Differential roles of tau class glutathione S-transferases in oxidative stress
AU - Kilili, Kimiti G
AU - Atanassova, Neli
AU - Vardanyan, Alla
AU - Clatot, Nicolas
AU - Al-Sabarna, Khaled
AU - Kanellopoulos, Panagiotis N
AU - Makris, Antonios M
AU - Kampranis, Sotirios C
PY - 2004/6/4
Y1 - 2004/6/4
N2 - The plant glutathione S-transferase BI-GST has been identified as a potent inhibitor of Bax lethality in yeast, a phenotype associated with oxidative stress and disruption of mitochondrial functions. Screening of a tomato two-hybrid library for BI-GST interacting proteins identified five homologous Tau class GSTs, which readily form heterodimers between them and BI-GST. All six LeGSTUs were found to be able to protect yeast cells from prooxidant-induced cell death. The efficiency of each LeGSTU was prooxidant-specific, indicating a different role for each LeGSTU in the oxidative stress-response mechanism. The prooxidant protective effect of all six proteins was suppressed in the absence of YAP1, a transcription factor that regulates hydroperoxide homeostasis in Saccharomyces cerevisiae, suggesting a role for the LeGSTUs in the context of the YAP1-dependent stress-responsive machinery. The different LeGSTUs exhibited varied substrate specificity and showed activity against oxidative stress by-products, indicating that their prooxidant protective function is likely related to the minimization of oxidative damage. Taken together, these results indicate that Tau class GSTs participate in a broad network of catalytic and regulatory functions involved in the oxidative stress response.
AB - The plant glutathione S-transferase BI-GST has been identified as a potent inhibitor of Bax lethality in yeast, a phenotype associated with oxidative stress and disruption of mitochondrial functions. Screening of a tomato two-hybrid library for BI-GST interacting proteins identified five homologous Tau class GSTs, which readily form heterodimers between them and BI-GST. All six LeGSTUs were found to be able to protect yeast cells from prooxidant-induced cell death. The efficiency of each LeGSTU was prooxidant-specific, indicating a different role for each LeGSTU in the oxidative stress-response mechanism. The prooxidant protective effect of all six proteins was suppressed in the absence of YAP1, a transcription factor that regulates hydroperoxide homeostasis in Saccharomyces cerevisiae, suggesting a role for the LeGSTUs in the context of the YAP1-dependent stress-responsive machinery. The different LeGSTUs exhibited varied substrate specificity and showed activity against oxidative stress by-products, indicating that their prooxidant protective function is likely related to the minimization of oxidative damage. Taken together, these results indicate that Tau class GSTs participate in a broad network of catalytic and regulatory functions involved in the oxidative stress response.
KW - Amino Acid Sequence
KW - Catalysis
KW - Dimerization
KW - Dose-Response Relationship, Drug
KW - Glutathione
KW - Glutathione Disulfide
KW - Glutathione Transferase
KW - Hydrogen-Ion Concentration
KW - Kinetics
KW - Lycopersicon esculentum
KW - Models, Molecular
KW - Molecular Sequence Data
KW - Oxidants
KW - Oxidative Stress
KW - Phenotype
KW - Precipitin Tests
KW - Protein Binding
KW - Protein Structure, Secondary
KW - Proto-Oncogene Proteins
KW - Proto-Oncogene Proteins c-bcl-2
KW - Saccharomyces cerevisiae
KW - Sequence Homology, Amino Acid
KW - Substrate Specificity
KW - Two-Hybrid System Techniques
KW - bcl-2-Associated X Protein
U2 - 10.1074/jbc.M309882200
DO - 10.1074/jbc.M309882200
M3 - Journal article
C2 - 15037622
SN - 0021-9258
VL - 279
SP - 24540
EP - 24551
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 23
ER -