Regulation of plasma membrane Ca2Â +-ATPase activity by acetylated tubulin: Influence of the lipid environment

► Tubulin inhibits PMCA activity in plasma membrane through a reversible interaction. ► When the enzyme is reconstituted in the presence of acidic or neutral lipids and low concentrations of tubulin, PMCA is activated. ► PMCA is activated independently of surrounding lipid composition at low tubulin concentrations. ► PMCA is activated mainly by reconstitution in acidic lipids at high tubulin concentrations. ► Regulation of PMCA activity by tubulin is dependent on lipid composition and tubulin concentration.