ATP6V1B2
Description
The ATP6V1B2 (ATPase H+ transporting V1 subunit B2) is a protein-coding gene located on chromosome 8.
ATP6V1B2, also known as V-type proton ATPase subunit B, brain isoform, encodes a component of vacuolar ATPase (V-ATPase), a multi-subunit enzyme responsible for acidifying eukaryotic intracellular organelles. This process is essential for functions such as protein sorting, zymogen activation, receptor-mediated endocytosis, and synaptic vesicle proton gradient generation. V-ATPase is composed of a cytosolic V1 domain and a transmembrane V0 domain. The V1 domain contains the ATP catalytic site and is comprised of three A, three B, and two G subunits, as well as a C, D, E, F, and H subunit. The protein encoded by ATP6V1B2 is one of two V1 domain B subunit isoforms and is the only B isoform highly expressed in osteoclasts. In melanocytic cells, ATP6V1B2 gene expression may be regulated by MITF.
ATP6V1B2 is a non-catalytic subunit of the V1 complex of vacuolar (H+)-ATPase (V-ATPase), a multi-subunit enzyme responsible for acidifying intracellular compartments. V-ATPase comprises a peripheral complex (V1) that hydrolyzes ATP and a membrane integral complex (V0) that translocates protons. In some cell types, V-ATPase is targeted to the plasma membrane where it acidifies the extracellular environment. ATP6V1B2 can partially compensate for the lack of ATP6V1B1 in renal intercalated cells and mediate secretion of protons (H+) into urine under baseline conditions, but not in conditions of acid load.
ATP6V1B2 is also known as ATP6B1B2, ATP6B2, DOOD, HO57, VATB, VPP3, Vma2, ZLS2.
Associated Diseases
- Zimmermann-Laband syndrome
- Zimmermann-Laband syndrome 2
- Autosomal dominant deafness-onychodystrophy syndrome
- DOORS syndrome
- Deafness, congenital, and onychodystrophy, autosomal dominant
