HYDROGEN SULFIDE PARTICIPATES IN ABADEPENDENT STOMATAL CLOSURE

GARCÍA-MATA, C,; LAMATTINA, L.

San Miguel de Tucumán

Congreso; XLV Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2009

SAIB

Endogenous gases had emerged as a mainstream topic in signal transduction research both in animals and plants. Among them, hydrogen sulfide (H S) is an emerging signaling molecule with 2 important functions in human physiology, it has been involved in sulfur-induced resistance in plant-pathogen interaction. In plants, it has been shown that L-cysteine desulfhydrase (L-CDES) releases H S d u r i n g L - c y s t e i n e me t a b o l i sm, wh i l e O- 2 acetylserine(thiol)lyase (OAS-TL) consumes H S during L- 2 cysteine synthesis. However, the mechanism of action and the biology of H S as a signaling molecule in plants it’s still in its 2 infancy. In the present work we report that the H S donor NaHS induces 2 stomatal closure in Vicia faba epidermal peels, in a dose dependent manner. In addition, when epidermal peels were treated with the inhibitor of L-CDES DL-Propargyglicine (PAG) ABA-dependent induction of stomatal closure was partially blocked. In order to correlate these effects at a whole plant level, we treated Impatiens walleriana plants with NaHS, and suspended the watering for four days Results show that H S treated plants were greener, and had a 2 Real Water Content (RWC) 20% higher than control plants, after the imposed stress. Consequently it is postulated that H S is 2 involved in the regulation of stomatal closure through its participation in some of the ABA evoked pathways. Supported by UMNdP-CONICET and AMPCyT