Popis: |
There has been a rapidly growing list of ATP-fueled ion pumps. Most of these are H+-transporting ATPases ranging from the mitochondrial F1F0 ATPase through the H+ pump of intracellular organelles to the gastric H+-K+ ATPase (Racker, 1976; Cidon and Nelson, 1983; Sachs et al, 1976). In addition to the Ca2+ ATPase of sarcoplasmic reticulum and plasma membrane (Schatzman, 1982), the role of the Ca2+ pump of rough endoplasmic reticulum in fueling a facultative Ca2+ store has been recognized (Berridge, 1984), and its properties are currently of interest. |