IQUIFIB   02644
INSTITUTO DE QUIMICA Y FISICOQUIMICA BIOLOGICAS "PROF. ALEJANDRO C. PALADINI"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
ROLE OF NADPH OXIDASES IN THE REGULATION OF OXIDATIVE METABOLISM UNDER CADMIUM STRESS
Autor/es:
DK GUPTA; LB PENA; MC ROMERO-PUERTAS; LM SANDALIO
Lugar:
Budapest
Reunión:
Conferencia; 10th International Conference on Reactive Oxygen and Nitrogen Species in Plants; 2011
Institución organizadora:
Plant Oxygen Group of the Society for Free Radical Research-Europe
Resumen:
Cadmium is toxic for plants, animals and humans. Different approaches have demonstrated that oxidative stress is one
of the primary effects of Cd exposure, although the sources of reactive oxygen
species involved are not well established (1). In this work, the role of NADPH
oxidases as a source of ROS has been studied by using AtrbohC, D & F Arabidopsis mutants. In these mutants we
analyzed the effect of 25 and 100 µM Cd for 1 and 5
days on growth parameters, H2O2 and NO accumulation, and on
the activity and transcript levels of some antioxidants.
Cadmium significantly decreased the germination rate
of seeds and leaf biomass production at 100µM and after 5 days of treatment in
WT plants, although this reduction was not observed in AtrbohF. Lipid peroxidation and H2O2 accumulation
increased in line with the Cd concentration, mainly after 5 days of treatment, and
no differences were observed between WT and Atrboh
mutants. A different behaviour was observed with NO accumulation, which
decreased with the treatment in all plants analyzed except AtrbohC. In WT plants, catalase activity slightly increased with
the treatment and opposite effect was observed in Atrboh mutants, mainly due to changes in CAT2 expression. Cadmium increased
glutathione reductase activity mostly in the mutants after 5 days of treatment
with 100 µM Cd, although no changes were observed at transcriptional level. GSH
and ASC content were also affected by the treatment mainly in AtrbohF mutants. The activity of glycolate oxidase was also induced
by 100 µM Cd in the mutants due to up-regulation of GOX3. In conclusion,
down-regulation of different NADPH oxidases produces differential responses to
Cd in Arabidopsis plants which affect
mainly the regulation of antioxidant expression and photorespiration