Arabidopsis thaliana frataxin (AtFH) is involved in oxidative stress and iron homeostasis

MARTIN, M.; MALIANDI, M. V.; BUSI, M. V.; LAMATTINA, L.; DIEGO FABIAN GOMEZ CASATI; EDUARDO ZABALETA

Pinamar

Congreso; XLI Reunión Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB); 2005

Frataxin is a mitochondrial protein that is conserved throughout evolution, from bacteria to yeasts, humans and plants. The function of frataxin is still essentially unknown. It has been postulated that this protein is involved in mitochondrial energy and iron metabolism and also has a protective role against oxidants. Recently, its plant homologue was identified in Arabidopsis thaliana. Current data concerning mammalian mitochondrial Fe metabolism suggest an intricate and complicated web of supply and demand involving at least two major Fe-requiring pathways, that is, the generation of [Fe-S] clusters and heme synthesis. It was recently hypothesized that frataxin acts as a metabolic switch. In this work, to investigate whether frataxin is involved in iron homeostasis we study the correlation of AtFH expression with iron availability in Arabidopsis plants. Results obtained show that frataxin expression is up-regulated by iron-deficiency, possibly mediated by NO and a decrease in hydrogen peroxide content in yeast mutants expressing AtFH. Our results support the involvement of AtFH in iron homeostasis and oxidative stress in plant cells.