Transgenic Arabidopsis plants expressing the rice dehydroascorbate reductase gene are resistant to salt stress.
Vitamin C (l-ascorbate) is important for antioxidative and metabolic functions in both plants and humans. Ascorbate itself is oxidized to dehydroascorbate during the process of antioxidation, and dehydroascorbate reductase (DHAR, EC 1.8.5.1) re-reduces the oxidized ascorbate. Therefore, this enzyme is assumed to be critical for ascorbate recycling. Here we show that the expression of rice DHAR in transgenic Arabidopsis thaliana enhanced resistance to salt stress. Salt tolerance was remarkably improved despite slight increases in DHAR activity and total ascorbate. This study provides direct evidence for the importance of DHAR in salt tolerance.
Ushimaru
Takashi
T
Department of Biology and Geoscience, Faculty of Science, Shizuoka University, 836 Ohya, Shizuoka 422-8529, Japan. sbtushi@ipc.shizuoka.ac.jp
Nakagawa
Tomofumi
T
Fujioka
Yuko
Y
Daicho
Katsue
K
Naito
Makiko
M
Yamauchi
Yuzo
Y
Nonaka
Hideko
H
Amako
Katsumi
K
Yamawaki
Kazuki
K
Murata
Norio
N
D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000502:physiology*; D001205:Ascorbic Acid / Q000378:metabolism*; D017343:Genes, Plant; D012275:Oryza / Q000235:genetics*; D010088:Oxidoreductases / Q000235:genetics* / Q000378:metabolism*; D030821:Plants, Genetically Modified; D012965:Sodium Chloride / Q000494:pharmacology*; D014170:Transformation, Genetic
D012965:Sodium Chloride; D010088:Oxidoreductases; C020666:glutathione dehydrogenase (ascorbate); D001205:Ascorbic Acid