INVESTIGADORES
CAMPETELLI Alexis Nazareno
congresos y reuniones científicas
Título:
EFFECT OF TUBULIN IN PMCA ACTIVITY DEPENDS ON LIPID COMPOSITION WHERE THE ENZYME IS IMMERSED.
Autor/es:
MONESTEROLO N E; CAMPETELLI A N; AMAIDEN M R; SANTANDER V; PREVITALI G; CASALE C H
Lugar:
Puerto Madryn
Reunión:
Congreso; SAIB; 2010
Institución organizadora:
SAIB
Resumen:
In previous work we demostrated that acetylated tubulin forms a complex with PMCA (Ca2+-ATPase) and the formation of the complex in vivo inhibits the enzimatic activity. We recently demonstrated that the effect of tubulin on PMCA activity is dependent on the environment in which both proteins are immersed. The reconstitution of the PMCA in liposomes and the subsequent addition of tubulin caused the activation of the PMCA. In this work we study the effect of tubulin on the PMCA activity reconstituted in different lipids. For this proposes PMCA was purified from rat brain and reconstituted in liposomes with diacylglycerol (DAG),lipid acid (BE) and phosphatidic acid (PA) or phosphatidylcholine (PC). Results shown that tubulin is able to activating PMCA independently of the tubulin concentration when the enzyme was reconstituted in BE and PA. However, the effecto of tubulin was dependent on the tubulin concentration when the reconstitution was done in DAG or PC, tubulin concentrations below 25 μg/ml activates PMCA more than two times, whereas higher concentrations inhibited the enzymatic activity. These results indicate that the effect of tubulin on the PMCA activity is dependent on lipid composition in which the enzyme is immersed and the tubulin concentration.