V-type proton ATPase 116 kDa subunit a isoform 4 (ATP6V0A4)

V-type proton ATPase 116 kDa subunit a isoform 4 (ATP6V0A4) is a membrane-bound component of the multisubunit V-ATPase enzyme complex, responsible for transporting protons across intracellular and plasma membranes through ATP hydrolysis. The a4 isoform is especially critical in the kidney and the inner ear, where it acidifies urine and helps maintain the inner ear’s pH. Mutations in ATP6V0A4 lead to distal renal tubular acidosis, metabolic bone disease, and sensorineural hearing loss. The V-ATPase consists of a cytosolic V1 domain (ATP hydrolysis) and a membrane-embedded V0 domain (proton translocation), with the a4 subunit forming part of the transmembrane channel. While the enzyme complex is a validated physiological target, direct therapeutic modulation is limited because of fundamental cellular roles throughout the body[1][2][3][4][5].

Other names

V-type proton ATPase 116 kDa subunit a 4ATPase H+ transporting V0 subunit a4Vacuolar proton translocating ATPase 116 kDa subunit a isoform 4Vacuolar proton translocating ATPase 116 kDa subunit a kidney isoformV-ATPase subunit a4VPP2RDRTA2RTADRA4ATP6N1BATP6N2DRTA3RTA1CSTV1VPH1

Inhibition of proton transport (blocks acidification of intracellular/extracellular compartments by inhibiting V-ATPase activity overall; this is the mechanism of generic V-ATPase inhibitors, experimentally used)