EXTRACELULAR ATP (eATP) INDUCES PHOSPHATIDIC ACID AND NITRIC OXIDE IN TOMATO CELL SUSPENSIONS.

FORESI, N. P.; SUELDO, D.; CASALONGUE, C.; LAMATTINA, L.; LAXALT, A.M.

rosario

Congreso; SAFV; 2008

SAFV

ATP is a vital molecule used by living organisms as a universal source of energy. In animals, extracellular ATP (eATP) is a well-documented regulatory signal involved in numerous physiological processes. eATP release Ca2+ from internal stores via the phospholipase C (PLC) derived inositol-3-phosphate (IP3). In plants, eATP induces increases in citoplasmic Ca2+ concentration, however it is not know whether PLC-derived IP3 is regulating this process. PLC has role in signaling generating two-second messengers IP3 and diacylglycerol (DAG). In plants DAG is converted to phosphatidic acid (PA) via DAG kinase (DGK). Still another source of PA is phospholipase D (PLD). The aim of the present work is study whether eATP induce phospholipid signaling in tomato cell suspensions. Our results show that eATP induces a biphasic PA response at different eATP doses. Time course experiments showed that PA is generated within minutes and the contribution of PLD and/or PLC pathway is being studied. Another second messenger induced by eATP in plants is NO. We studied the cross talk between NO, Ca2+ and PLC signaling during eATP treatment. Our results resembled the ones already described in animals where eATP induces PLC and then NO productions takes place. Supported by CONICET, ANPCyT and UNMdP