Ascorbate and glutathione protect Arabidopsis plants growing in iron deficient conditions.

RAMIREZ LEONOR; LAMATTINA LORENZO

Potrero de Funes

Congreso; SAIB; 2011

Ascorbate and glutathione protects Arabidopsis plants growing in iron deficient conditions Leonor Ramírez, Lorenzo Lamattina Instituto de Investigaciones Biológicas-CONICET, Universidad Nacional de Mar del Plata, Argentina.  Iron is an essential micronutrient required for a wide variety of cellular functions in plant growth and development. Chlorosis is the first visible symptom in iron deficient plants. As a consequence, cellular redox homeostasis is disturbed due mainly to the diminished photosynthetic activity. Both ascorbate (Asc) and glutathione (GSH) are multifunctional metabolites that are important in redox balancing. We were interested in studying the effect of Asc and GSH during iron deficiency in Arabidopsis plants. Either, Asc or GSH prevented the chlorosis in iron deficient plants without involving changes in hydrogen peroxide content, a ROS suspected to increase during iron deficiency stress. In addition, the content of the iron-sulfur protein ferredoxin 2 (Fd2) and the activity of the heme protein ascorbate peroxidase (APX), were diminished in leaves of iron deficient plants. Interestingly, Asc or GSH treatments were able to preserve the Fd2 levels and APX activity at the same level found in iron sufficient plants. Works are in progress to see if the protection mediated by Asc and GSH is due to improving internal iron availability increasing the cellular labile iron pool. Supported by CONICET, ANPCyT, UNMdP.