Stimulation of yeast 3-phosphoglycerate kinase gene promoter by paraquat.
Yeast cells exposed to adverse conditions employ a number of defense mechanisms in order to respond effectively to the stress and sustain a high proliferation rate. It has been shown that several glycolytic enzymes are induced upon heat treatment of yeast. In this work, we used a reporter plasmid construct to study the effects of oxidative stress, induced by the O(*-)(2)-generating compound paraquat (PQ), on the yeast 3-phosphoglycerate kinase gene (PGK) promoter. Our results show that (i) moderate, as opposed to excessive, doses of PQ induce increased stimulation of the PGK promoter, at midlogarithmic phase of growth; and (ii) the thiol antioxidant N-acetylcysteine cancels this stimulatory effect. These observations may represent one aspect of a more general role for glycolysis in maintaining the energy pools of yeast cells under stress.
Vassallo
N
N
Department of Physiology and Biochemistry, University of Malta, Msida, MSD 06, Malta.
Galea
D R
DR
Bannister
W H
WH
Balzan
R
R
D000111:Acetylcysteine / Q000494:pharmacology; D003001:Cloning, Molecular; D004926:Escherichia coli; D006358:Hot Temperature; D007700:Kinetics; D010269:Paraquat / Q000494:pharmacology*; D010735:Phosphoglycerate Kinase / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000187:drug effects*; D011994:Recombinant Proteins / Q000096:biosynthesis; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D013481:Superoxides; D001616:beta-Galactosidase / Q000096:biosynthesis / Q000235:genetics
D011994:Recombinant Proteins; D013481:Superoxides; D010735:Phosphoglycerate Kinase; D001616:beta-Galactosidase; D010269:Paraquat; D000111:Acetylcysteine