Role of AtHscB in mitochondria iron metabolism in A. thaliana plants

LAURA LEADEN; MARIANA MARTÍN; MARÍA V. BUSI; DIEGO F. GOMEZ-CASATI

Rosario

Conferencia; 8th International Conference for Plant Mitochondrial Biology ICPMB 2013; 2013

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 complex cellular machinery. In our laboratory we have characterized A. thaliana transgenic lines overexpressing AtHscB (co-chaperone, involved in the Fe-S cluster biogenesis in mitochondria). These lines grow on iron normal conditions; show an impaired translocation of Fe from the roots to the shoots; showing altered iron content, metabolism, and distribution. In addition, the induction of ferroquelate reductase (FRO2) activity is in agreement with the sensing of iron deficiency. We also evaluate the effect of the deficiency of AtHscB on iron metabolism in A. thaliana plants. Two AtHscB knock down mutant plants (mh1 and mh2) were analyzed. We determined FRO2 activity in mh1 and mh2 mutants grown under normal or iron deficient conditions. Results show that FRO2 activity is similar in wt plants in both conditions and it does not change even when mh1or mh2 mutants were grown on iron deficient conditions. Furthermore the mutant lines are more resistant to iron deficiency but showing an increased iron content in roots and shoots. Our results suggest that AtHscB could respond to changes in iron metabolism and the deficiency of AtHscB might produce an alteration of the iron transport between roots to shoot.