Conversion of L-galactono-1,4-lactone to L-ascorbate is regulated by the photosynthetic electron transport chain in Arabidopsis.
In this study we focused on the effects of light irradiation and the addition of L-galactono-1,4-lactone (L-GalL) on the conversion of exogenous L-GalL to L-ascorbate (AsA) and the total AsA pool size in detached leaves of Arabidopsis plants and transgenic plants expressing the rat L-gulono-1,4-lactone oxidase gene. Increases in the total AsA level in L-GalL-treated leaves depended entirely on light irradiation. Treatment with an inhibitor of photosynthetic electron transport together with L-GalL reduced the increase in total AsA under light. Light, particularly the redox state of photosynthetic electron transport, appeared to play an important role in the regulation of the conversion of L-GalL to AsA in the mitochondria, reflecting the cellular level of AsA in plants.
Department of Advanced Bioscience, Faculty of Agriculture, Kinki University, Nara, Japan.
Yukinori
Y
Yabuta
Takanori
T
Maruta
Ayana
A
Nakamura
Takahiro
T
Mieda
Kazuya
K
Yoshimura
Takahiro
T
Ishikawa
Shigeru
S
Shigeoka
D017360:Arabidopsis / Q000201:enzymology*; D001205:Ascorbic Acid / Q000096:biosynthesis*; D045222:Electron Transport Chain Complex Proteins / Q000037:antagonists & inhibitors / Q000378:metabolism*; D007783:Lactones / Q000378:metabolism*; D008027:Light; D010788:Photosynthesis; D018515:Plant Leaves / Q000201:enzymology; D030821:Plants, Genetically Modified; D013400:Sugar Acids / Q000378:metabolism*
D045222:Electron Transport Chain Complex Proteins; D007783:Lactones; D013400:Sugar Acids; C534014:galactono-1,4-lactone; C007813:galactonolactone; D001205:Ascorbic Acid