Vacuolar ATPase accessory protein 1 (ATP6AP1)

Vacuolar ATPase accessory protein 1 (ATP6AP1) is an accessory subunit of the V-type proton ATPase (V-ATPase), a multi-subunit enzyme complex responsible for acidification of eukaryotic intracellular organelles, which is essential for normal protein sorting, enzyme precursor activation, and receptor-mediated endocytosis. ATP6AP1 helps guide and assemble the V-ATPase complex to its correct subcellular localization, especially in secretory vesicles of neuroendocrine and other regulated cells. Pathogenic variants in ATP6AP1 cause X-linked congenital disorder of glycosylation (CDG), characterized primarily by liver disease, with variable immunodeficiency and connective tissue abnormalities, and less frequently neurologic features. The gene is critical for basic cellular processes via its role in proton transport and membrane dynamics, and defects cause severe multi-organ phenotypes.

Other names

ATPase H+ transporting accessory protein 1VATPS1XAP3ATP6IP1ATP6S1XAP-3Ac4516ACF2V-type proton ATPase subunit S1V-ATPase Ac45 subunitV-ATPase S1 accessory proteinVacuolar ATPase subunit S1Vacuolar proton pump subunit S1X-associated protein 3Protein XAP-3Epididymis secretory sperm binding proteinATPase, H+ transporting, lysosomal (vacuolar proton pump), subunit 1ATPase, H+ transporting, lysosomal accessory protein 1ATPase, H+ transporting, lysosomal interacting protein 1H-ATPase subunit

Not directly targeted by drugs as a single subunit; however, the V-ATPase complex can be inhibited by small molecules, affecting processes like organelle acidification and trafficking