Role of AtHscB in plant iron metabolism

LEADEN, L; BUSI, M. V.; DIEGO FABIAN GOMEZ CASATI

Mendoza

Congreso; XLVIII Reunion SAIB; 2012

SAIB

Iron is an essential nutrition element in all organisms. It is fundamental to the metabolism of mitochondria and chloroplasts. Iron-sulfur (Fe-S) clusters are produced inside both organelles and the assembly and maturation of Fe-S proteins require a complex cellular machinery. In our laboratory we have characterized different genes and proteins that are postulated to be involved in the (Fe-S) cluster biosynthesis in Arabidopsis thaliana. In this work we evaluate the effect of the overexpression of AtHscB (co-chaperone, involved in the Fe-S cluster biogenesis) on iron metabolism in A. thaliana plants. Two transgenic lines overexpressing AtHscB were analyzed. We measure the transcript level of several genes that are regulated by iron by QPCR. Results show that the mRNA levels of ferrochelate reductase (FRO2) and a metal transporter (IRT1) (involved in iron transport) are increased about 11- and 21-fold, respectively. By contrast, the transcript level of ferritin1 (AtFer1) was decreased 5-fold. Furthermore, the histochemical detection of iron deposits using the Perls method showed an increased of iron content in roots. Our results suggest an alteration of iron metabolism, content and distribution in the transgenic lines, in addition, the induction of FRO2 and IRT1 in the s-HscB lines are in agreement with the sensing of iron deficiency.