INVESTIGADORES
ATTALLAH Carolina Veronica
congresos y reuniones científicas
Título:
Sco proteins of plants are involved in COX biogenesis, copper homeostasis and redox metabolism
Autor/es:
ATTALLAH, C.V.; WELCHEN, E.; MARTÍN, A.P.; PALATNIK, J.F.; GONZÁLEZ, D.H.
Lugar:
San Miguel de Tucumán, Tucumán. Argentina.
Reunión:
Congreso; XLV Reunión anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB); 2009
Institución organizadora:
Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB)
Resumen:
In Arabidopsis thaliana, AtSCO1 and AtSCO2 encode proteins with homology to the SCO proteins involved in cytochrome coxidase (COX) biogenesis in other organisms. Phylogenetic analysis indicated that the two genes have diverged before the emergence of flowering plants. Heterozygote plants with a T-DNA insertion in the second exon of AtSCO1 produce 25% abnormal seeds with defective embryos arrested at the heart or torpedo stage and no homozygote mutant plants can be detected. Embryos from abnormal seeds lack COX activity, suggesting that AtSCO1 function is essential for COX assembly and for early stages of embryogenesis. Homozygote mutant plants obtained by complementation with the AtSCO1 cDNA show a defect in pollen tube elongation, probably indicating a requirement of AtSCO1 for pollen function. Plants that overexpress AtSCO1 have altered responses to copper, including a different rate of root elongation, altered ratios of superoxide dismutase isoenzymes and increased activity of the miR398 promoter. Plants that lack AtSCO2 expression develop normally but show retarded growth during the reproductive phase and alterations related with redox metabolism. The results suggest that AtSCO1 is involved in COX biogenesis and that it also has a role in maintaining copper homeostasis in plants. AtSCO2, that lacks the copper binding motif, may participate in mitochondrial redox metabolism.