Mechanisms of the selenium tolerance of the Arabidopsis thaliana knockout mutant of sulfate transporter SULTR1;2.
We investigated the mechanism of selenium (Se) tolerance using an Arabidopsis thaliana knockout mutant of a sulfate transporter, sultr1;2. Se stress inhibited plant growth, decreased chlorophyll contents, and increased protein oxidation and lipid peroxidation in the wild type, whereas the sultr1;2 mutation mitigated damage of these forms, indicating that sultr1;2 is more tolerant of Se than the wild type is. The accumulation of symplastic Se was suppressed in sultr1;2 as compared to the wild type, and the chemical speciation of Se in the mutant was different from that in the wild type. Regardless of Se stress, the activities of ascorbate peroxidase, catalase, and peroxidase in the mutant were higher than in the wild type, while the activity of superoxide dismutase in the mutant was the same as in the wild type. These results suggest that the sultr1;2 mutation confers Se tolerance on Arabidopsis by decreasing symplastic Se and maintaining antioxidant enzyme activities.
Graduate School of Natural Science and Technology, Okayama University, Japan.
Misao
M
Ohno
Misugi
M
Uraji
Yasuaki
Y
Shimoishi
Izumi C
IC
Mori
Yoshimasa
Y
Nakamura
Yoshiyuki
Y
Murata
D000222:Adaptation, Physiological / Q000235:genetics; D027321:Anion Transport Proteins / Q000172:deficiency / Q000235:genetics*; D000975:Antioxidants / Q000378:metabolism; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics*; D060387:Ascorbate Peroxidases / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D055786:Gene Knockout Techniques; D015227:Lipid Peroxidation / Q000187:drug effects / Q000235:genetics; D009154:Mutation; D018384:Oxidative Stress / Q000187:drug effects / Q000235:genetics; D010544:Peroxidases / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000187:drug effects / Q000378:metabolism; D055049:Salt Tolerance / Q000235:genetics*; D064586:Selenic Acid; D012643:Selenium / Q000378:metabolism / Q000494:pharmacology*; D018036:Selenium Compounds / Q000378:metabolism / Q000494:pharmacology*; D013312:Stress, Physiological / Q000235:genetics; D013482:Superoxide Dismutase / Q000378:metabolism
D027321:Anion Transport Proteins; D000975:Antioxidants; D029681:Arabidopsis Proteins; D018036:Selenium Compounds; C455460:Sultr1;2 protein, Arabidopsis; D010544:Peroxidases; D060387:Ascorbate Peroxidases; D002374:Catalase; D013482:Superoxide Dismutase; D012643:Selenium; D064586:Selenic Acid