Vacuolar-type ATPase (V-ATPase) is a highly conserved evolutionarily ancient enzyme with remarkably diverse functions in eukaryotic organisms. V-ATPases acidify a wide array of intracellular organelles and pumps protons across the plasma membranes of numerous cell types. V-ATPases couple the energy of ATP hydrolysis to proton transport across intracellular and plasma membranes of eukaryotic cells. It is generally seen as the polar opposite of ATP synthase because ATP synthase is a proton channel that uses the energy from a proton gradient to produce ATP. V-ATPase however, is a proton pump that uses the energy from ATP hydrolysis to produce a proton gradient.
Ca2+ ATPase is a form of P-ATPase that transfers calcium after a muscle has contracted. The two kinds of calcium ATPase are:
The plasma membrane Ca2+ ATPase (PMCA) is a transport protein in the plasma membrane of cells and functions to remove calcium (Ca2+) from the cell. PMCA function is vital for regulating the amount of Ca2+ within all eukaryotic cells. There is a very large transmembrane electrochemical gradient of Ca2+ driving the entry of the ion into cells, yet it is very important that they maintain low concentrations of Ca2+ for proper cell signalling. Thus, it is necessary for cells to employ ion pumps to remove the Ca2+. The PMCA and the sodium calcium exchanger (NCX) are together the main regulators of intracellular Ca2+ concentrations. Since it transports Ca2+ into the extracellular space, the PMCA is also an important regulator of the calcium concentration in the extracellular space.
Sodium/potassium-transporting ATPase subunit alpha-1 is an enzyme that in humans is encoded by the ATP1A1 gene.
Sodium/potassium-transporting ATPase subunit alpha-2 is a protein which in humans is encoded by the ATP1A2 gene.
Calcium-transporting ATPase type 2C member 1 is an enzyme that in humans is encoded by the ATP2C1 gene.
Plasma membrane calcium-transporting ATPase 1 is a plasma membrane Ca2+
ATPase, an enzyme that in humans is encoded by the ATP2B1 gene. It's a transport protein, a translocase, a calcium pump EC 7.2.2.10.
Plasma membrane calcium-transporting ATPase 2 is an enzyme that in humans is encoded by the ATP2B2 gene.
Sodium/potassium-transporting ATPase subunit beta-1 is an enzyme that in humans is encoded by the ATP1B1 gene.
V-type proton ATPase 16 kDa proteolipid subunit is an enzyme that in humans is encoded by the ATP6V0C gene.
Sarcoplasmic/endoplasmic reticulum calcium ATPase 3 is an enzyme that in humans is encoded by the ATP2A3 gene.
V-type proton ATPase subunit B, brain isoform is an enzyme that in humans is encoded by the ATP6V1B2 gene.
V-type proton ATPase subunit C 1 is an enzyme that in humans is encoded by the ATP6V1C1 gene.
V-type proton ATPase 116 kDa subunit a isoform 1 is an enzyme that in humans is encoded by the ATP6V0A1 gene.
V-type proton ATPase catalytic subunit A is an enzyme that in humans is encoded by the ATP6V1A gene.
V-type proton ATPase subunit G 2 is an enzyme that in humans is encoded by the ATP6V1G2 gene.
V-type proton ATPase subunit G 3 is an enzyme that in humans is encoded by the ATP6V1G3 gene.
V-type proton ATPase subunit e 1 is an enzyme that in humans is encoded by the ATP6V0E1 gene.
Plasma membrane calcium-transporting ATPase 3 is an enzyme that in humans is encoded by the ATP2B3 gene.
Calcium pumps are a family of ion transporters found in the cell membrane of all animal cells. They are responsible for the active transport of calcium out of the cell for the maintenance of the steep Ca2+ electrochemical gradient across the cell membrane. Calcium pumps play a crucial role in proper cell signalling by keeping the intracellular calcium concentration roughly 10,000 times lower than the extracellular concentration. Failure to do so is one cause of muscle cramps.
