Effect of mitochondrial ascorbic acid synthesis on photosynthesis

SENN, MARÍA EUGENIA; GERGOFF GROZEFF, GUSTAVO; ALEGRE, MATÍAS LEONEL; BARRILE, FRANCO; DE TULLIO, MARIO C; BARTOLI, CARLOS GUILLERMO

PLANT PHYSIOLOGY AND BIOCHEMISTRY

ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER

Lugar: Paris; Año: 2016 vol. 104 p. 29 - 35

0981-9428

Ascorbicacid (AA) is synthesized in plant mitochondria through the oxidation of l-galactono-1,4-lactone (l -GalL) and then distributed to different cell compartments.AA-deficient Arabidopsis thaliana mutants (vtc2) and exogenous applications of l-GalL were used to generate plants with different AAcontent in their leaves. This experimental approach allows determining specificAA-dependent effects on carbon metabolism. No differences in O2uptake, malic and citric acid and NADH content suggest that AA synthesis oraccumulation did not affect mitochondrial activity; however, l -GalL treatment increased CO2 assimilationand photosynthetic electron transport rate in vtc2 (but not wt) leaves demonstrating a stimulation ofphotosynthesis after l-GalL treatment. Increased CO2 assimilationcorrelated with increased leaf stomatal conductance observed in l-GalL-treated vtc2plants.