THE PLASMA-MEMBRANE CALCIUM-PUMP - A PHYSIOLOGICAL PERSPECTIVE ON ITSREGULATION

This review focuses on the physiological role of the plasma membrane C a2++Mg2+-dependent adenosine triphosphatase (PM Ca2+-ATPase) in cellul ar signalling. Particular attention has been paid to the regulation of the PM Ca2+-ATPase (PM Ca2+ pump) by calmodulin, proteases, protein k inases, acidic phospholipids and oligomerization in intact cells, We a lso review recent work investigating the possible regulation of the PM Ca2+ pump by G proteins and agonists, The source of adenosine triphos phate (ATP) and Ca2+ in fuelling and activating the Ca2+ pump is discu ssed, as well as the possible role of the PM Ca2+-ATPase in subplasmam embrane Ca2+ regulation, The physiological implication of the localisa tion of the PM Ca2+ pump in caveolae is also considered.