V-type proton ATPase 21 kDa proteolipid subunit c'' (ATP6V0B)

V-type proton ATPase 21 kDa proteolipid subunit c'' (ATP6V0B) is an integral membrane protein forming part of the V0 sector of vacuolar ATPase (V-ATPase), a multisubunit enzyme complex that acidifies intracellular organelles such as endosomes, lysosomes, and secretory vesicles in eukaryotic cells[1][3][4][6]. The V-ATPase consists of the ATP-hydrolyzing peripheral V1 domain and the proton-translocating membrane-embedded V0 domain, with ATP6V0B constituting one of the proteolipid subunits of the V0 proton channel[1][2][4]. Organelle acidification by V-ATPase is essential for processes including protein sorting, activation of hydrolytic enzymes, receptor-mediated endocytosis, neurotransmitter loading into synaptic vesicles, and general vesicle trafficking[1][3][4][5]. Dysfunction of V-ATPase or its subunits, including ATP6V0B, is implicated in rare congenital diseases (such as severe congenital neutropenia), cancer progression, and metabolic bone disorders, due to the centrality of pH regulation in cellular homeostasis[1][3][5]. Direct subunit-specific drugs are not available, but several non-specific V-ATPase inhibitors are used in research contexts[6].

Other names

ATPase H+ transporting V0 subunit bHATPLVMA16ATP6FATPase, H+ transporting, lysosomal 21kDa, V0 subunit bV-type proton ATPase 21 kDa proteolipid subunit c''Vacuolar proton pump 21 kDa proteolipid subunit c''V-ATPase 21 kDa proteolipid subunit c''V-ATPase subunit bATPase, H+ transporting, lysosomal, 21-KD, V0 subunit C-primeVacuolar ATP synthase 21 kDa proteolipid subunitH(+)-transporting two-sector ATPase, subunit FV-ATPase subunit c''

V-ATPase inhibitors: block proton translocation, increase organelle pH, inhibit cellular acidification