H⁺-ATPase

H⁺-ATPase (also known as vacuolar ATPase, V-ATPase) is an enzyme transporter that functions to acidify intracellular compartments in eukaryotic cells. It is ubiquitously expressed and is present in endomembrane organelles such as vacuoles, lysosomes, the Golgi apparatus, chromaffin granules and coated vesicles, as well as in the plasma membrane.

H⁺-ATPase is a multisubunit complex composed of two domains. The V1 domain is responsible for ATP hydrolysis and the V0 domain is responsible for protein translocation. There are two main mechanisms of regulating H⁺-ATPase activity; recycling of H⁺-ATPase-containing vesicles to and from the plasma membrane and glucose-sensitive assembly/disassembly of the holoenzyme complex.

These transporters play an important role in processes such as receptor-mediated endocytosis, protein degradation and coupled transport. They have a function in bone reabsorption and mutations in the A3 gene cause recessive osteopetrosis. Furthermore, H⁺-ATPases have been implicated in tumor metastasis and regulation of sperm motility and maturation.

External sources of pharmacological information for H⁺-ATPase :

• BJP Guide

H⁺-ATPase Gene Data