Enhanced oxidative stress tolerance of tobacco transgenic plants overexpressing both ferredoxin-NADP(H) reductase and flavodoxin

LODEYRO, ANABELLA; RODRIGUEZ VIRASORO, RAMIRO; POLI, HUGO; TOGNETTI, VANESA; VALLE, ESTELA M.; CARRILLO, NÉSTOR.

San Carlos de Barilloche, ARGENTINA.

Congreso; XXXIX Reunión Anual de SAIB, XXXII Reunión Anual de SAB, Simposio de Proteínas; 2003

Sociedad Argentina de Biofísica, Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

Ferredoxin-NADP(H) reductases (FNR) catalyse the reversible electron transfer between two molecules of obligatory one-electron carriers as ferredoxin and flavodoxin (Fd) and a single molecule of NADP(H). Tobacco plants expressing Anabaena PCC7119 flavodoxin displayed enhanced tolerance to a variety of oxidative stress conditions. Recently, plants overexpressing FNR in chloroplasts were also obtained. In this work, we showed that this tobacco plants overexpressing FNR were more tolerant to excess light or to the reactive oxygen species generated by the herbicide methyl viologen (MV). We also evaluated the tolerance to MV of transgenic plants overexpressing both FNR and the cyanobacterial flavodoxin. These plants were obtained either by cross-fertilization or by transient expression of FNR directed to chloroplasts or cytosol developed by leaf infiltration with Agrobacterium tumefasciens carrying the appropriate plasmid construct. Results related to the enhanced tolerance to MV of these double transgenic plants will be discussed.