Biofortificación en Arabidopsis: Aumentando el contenido de hierro en tejidos

BALPARDA, M.; DIEGO FABIAN GOMEZ CASATI; PAGANI, M.A.

Rosario

Congreso; XIX Congreso y XXXVII Reunión de la Sociedad de Biología de Rosario; 2017

Sociedad de Biologia de Rosario

One of the most promising and sustainable strategies to improve iron nutrition is thebiofortification, i.e., the engineering of crops with a higher nutritional value of theedible parts. It is precisely for this reason that we decided to study the relationshipbetween the PAP-SAL1 retrograde signaling pathway and the iron metabolism. The sal1and xrn mutants accumulate between 50 and 70% more iron respect to the wild-typeplants, both in seeds, shoots and roots. Total iron quantification and histochemicalPerls-DAB staining confirmed accumulation of this metal in mutant plants. In addition,these mutants show an increase in the activity of enzymes that use iron as a cofactor inthe form of Fe-S and heme (i.e., aconitase and catalase) indicating that the accumulatedmetal is bioavailable. The sal1 is defective in a chloroplast (and probablymitochondrial) retrograde signaling pathway. This pathway affects the activity of 5´-3´exorribonucleases (XRNs) and the levels in multiple regulatory targets (miRNAamong others). In this sense, understanding the mechanisms implicated in mobilizationof iron from roots to the aerial parts and to seeds, the possible regulation of this process,and other potential control elements involved in sensing and signaling the iron cellularlevels, is of particular importance to adapt plant responses to improve uptake andtranslocation of the metal, in order to achieve and implement effective strategies ofbiofortification.