REGULACIÓN DE LOS GENES AtCOX17-1 Y AtCOX17-2, CODIFICANTES DE CHAPERONAS DE COBRE, EN CONDICIONES DE ESTRÉS BIÓTICO Y ABIÓTICO

CAROLINA V. ATTALLAH, ELINA WELCHEN Y DANIEL H. GONZÁLEZ

Chascomús, Buenos Aires. Argentina.

Congreso; XXVI Reunión Nacional de la Asociación Argentina de Fisiología Vegetal (SAFV); 2006

Sociedad Argentina de Fisiología Vegetal

AtCOX17 genes encode Arabidopsis thaliana homologues of the yeast metallochaperone Cox17p, involved in the delivery of copper for cytochrome c oxidase assembly. Two different AtCOX17 genes, located in chromosomes 1 and 3, are present in the Arabidopsis genome. Sequences upstream from the translation start sites of AtCOX17 genes, which include an intron located in the 5’ leader region, were introduced into plants in front of the gus gene. For both genes, expression was localized preferentially in young roots, anthers and siliques, but almost 10-fold higher GUS activity levels were observed in plants transformed with AtCOX17-1 upstream regions. Both promoters were induced to different extents by wounding, treatment of leaves with the bacterial pathogen Pseudomonas syringae, incubation with agents that produce oxidative stress and metals. AtCOX17-2 showed similar responses to these factors, while AtCOX17-1 was more strongly induced by relatively low (10-100 µM) copper. The results indicate that both AtCOX17 genes have similar, though not identical, expression characteritics and suggest the existence in their promoters of elements involved in tissue-specific expression and in responses to factors that may produce mitochondrial damage.