Mechanism of inhibition of Epigallocatechin on the Plasma Membrane Ca2+-ATPase.

RIESCO, A; RINALDI, D.E; FERREIRA GOMES, M; ROSSI, R.C; ROSSI, J.P.; MANGIALAVORI, I. .

Cordoba

Congreso; LII Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2016

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular

Keeping a low cytoplasmatic Ca2+ level depends on the active transport that sequester the cation from the cytoplasm. This is carried out by the Ca2+ATPases of the sarco-endoplasmic reticulum (SERCA) and the plasma membrane calcium pump (PMCA). PMCA is the main mechanism to fine-regulate the cytosolic Ca2+ levels. Is a P-type ATPase that form a phosphoenzyme by covalently binding with the -phosphate of ATP. PMCA is an integral protein of 138 KDa with 10 transmembrane domains which is regulated by calmodulin (CaM) that reversible binds to an auto-inhibitory site in the C-terminus. Catechins are known to have antioxidant, anticancer and cardioprotective effects. Epigallocatechin-3-gallate (EGCg) is the major catechin found in green tea that is responsible for those beneficial properties. EGCg is able to modify the intracellular Ca2+ levels both in excitable and non-excitable cells. Previous studies have shown that EGCg inhibits Na+/K+-ATPase through the interaction with membrane phospholipids. In this work, we had studied the effect and mechanism of EGCg on PMCA activity.