INVESTIGADORES
LODEYRO Anabella Fernanda
congresos y reuniones científicas
Título:
Tobacco plants overexpressing ferredoxin-NADP(H) reductases display enhanced stress tolerance
Autor/es:
LODEYRO, ANABELLA FERNANDA; RODRIGUEZ VIRASORO, RAMIRO; GIRÓ, MARIANA; POLI, HUGO; VALLE, ESTELA MARTA; CARRILLO, NÉSTOR
Lugar:
Rosario, ARGENTINA
Reunión:
Congreso; XLII Reunion Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2006
Institución organizadora:
Sociedad Argentina de Investigación en Bioquímica y Biología Molecular
Resumen:
Ferredoxin-NADP(H)
reductase (FNR) catalyses the last step of photosynthetic electron transport in
chloroplasts, driving electrons from two molecules of ferredoxin to a single
molecule of NADP+. Antisense tobacco plants with reduced amounts of
FNR display diminished photosynthetic activity (Hajirezaei et al Plant J. (2002) 29:281)
and enhanced photo-oxidative damage (Palatnik et al Plant J. (2003) 35:332).
Furthermore, in response to oxidative stress Escherichia coli induces the expression of the flavoprotein FNR and
its substrate flavodoxin (Krapp et alJ Bacteriol. (2002) 184:1474).
In order to investigate if the overexpression of this enzyme improves oxidative
stress tolerance in plants we prepared transgenic Nicotiana tabacum cv. Petit Havana plants expressing pea or
cyanobacterial FNR from Anabaena PCC7119. In this work we evaluate the
photosynthetic efficiency of the transgenic lines using fluorescence
chlorophyll measurements, CO2 fixation rates and biomass
accumulation. We found that FNR overexpression had no effect on growth or
photosynthetic parameters. On the other hand, we studied tolerance to oxidative
stress using high light treatments or redox-cycling herbicides that propagate
reactive oxygen species, such as methyl viologen (MV). Interestingly, the
transgenic plants with higher levels of the alien protein exhibited augmented
tolerance to photooxidative damage and MV.