Cysteine synthase overexpression in tobacco confers tolerance to sulfur-containing environmental pollutants.
Cysteine (Cys) synthase [O-acetyl-L-Ser(thiol)-lyase, EC 4.2.99.8; CSase] is responsible for the final step in biosynthesis of Cys. Transgenic tobacco (Nicotiana tabacum; F(1)) plants with enhanced CSase activities in the cytosol and in the chloroplasts were generated by cross-fertilization of two transformants expressing cytosolic CSase or chloroplastic CSase. The F(1) transgenic plants were highly tolerant to toxic sulfur dioxide and sulfite. Upon fumigation with 0.1 microL L(-1) sulfur dioxide, the Cys and glutathione contents in leaves of F(1) plants were increased significantly, but not in leaves of non-transformed control plants. Furthermore, the leaves of F(1) plants exhibited the increased resistance to paraquat, a herbicide generating active oxygen species.
Noji
M
M
Graduate School of Pharmaceutical Sciences, Department of Molecular Biology and Biotechnology, Chiba University, Yayoi-cho 1-33, Inage-ku, Chiba 263-8522, Japan.
Saito
M
M
Nakamura
M
M
Aono
M
M
Saji
H
H
Saito
K
K
D000222:Adaptation, Physiological; D002736:Chloroplasts / Q000201:enzymology; D003433:Crosses, Genetic; D003545:Cysteine / Q000378:metabolism; D003547:Cysteine Synthase / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D003600:Cytosol / Q000201:enzymology; D004351:Drug Resistance; D004785:Environmental Pollutants / Q000494:pharmacology*; D005978:Glutathione / Q000378:metabolism; D006540:Herbicides / Q000494:pharmacology; D018384:Oxidative Stress; D010269:Paraquat / Q000494:pharmacology; D018515:Plant Leaves / Q000187:drug effects / Q000378:metabolism; D030821:Plants, Genetically Modified; D010947:Plants, Toxic; D013455:Sulfur / Q000494:pharmacology*; D014026:Nicotiana / Q000187:drug effects / Q000201:enzymology* / Q000502:physiology
D004785:Environmental Pollutants; D006540:Herbicides; D013455:Sulfur; D003547:Cysteine Synthase; D005978:Glutathione; D003545:Cysteine; D010269:Paraquat