Frataxin deficiency affect chloroplast functions.

TUROWSKI, V.; MALIANDI, M. V.; ARAYA, A.; BUSI, M. V.; DIEGO FABIAN GOMEZ CASATI

Mendoza

Congreso; XLVIII Reunion SAIB; 2012

SAIB

Frataxin is aniron binding protein highly conservedthroughout evolution. It is involved invarious processes such as iron homeostasis, respiration, maturation ofFe-S proteins, hememetabolism, control of ROS and protection against oxidative damage. In yeast, mammals and plants frataxin has been described as a mitochondrial protein necessary for the normal function of this organelle. In silico studies predict mainly a mitochondrial localization for the Arabidopsis frataxin homologue (AtFH), but also a possible chloroplast localization. To determine the subcellular localization of AtFH, we constructedArabidopsis transgenic plants carrying the AtFH transit peptide fused to GFP. Using confocal lasermicroscopy we determined a dual localization of AtFH in both organelles. In addition, in order to determine the roles of AtFH in the chloroplast, we analyzed several parameters related to the physiological state of the chloroplasts in AtFH deficient plants. Results showedalterations in total iron and chlorophyll content, inthe photosynthetic capacity and in the activity of many Fe-S proteins. Results indicated that Frataxin is a functional protein in the chloroplast since its deficiency alters the normal physiology of this organelle.