V-type proton ATPase 116 kDa subunit a isoform 2 (ATP6V0A2) (ATP6V0A2)

The Vacuolar-type H+-ATPase a2 subunit (ATP6V0A2) is a critical transmembrane component of the V0 domain within the V-ATPase multisubunit complex. It functions as an ATP-dependent proton pump, primarily localized to the Golgi apparatus and early endosomes, where it maintains the acidic environment necessary for organelle function (UniProt: P0CAN7). This acidification is essential for the proper post-translational modification of proteins, particularly N- and O-linked glycosylation, as well as for efficient intracellular protein trafficking. Mutations in the ATP6V0A2 gene are the primary cause of autosomal recessive cutis laxa type IIA and wrinkly skin syndrome, which are characterized by skin abnormalities and developmental delays (PubMed: 18154859). In the context of oncology, the a2 subunit is often upregulated and contributes to the acidification of the tumor microenvironment, promoting protease activity and cancer cell invasion (PubMed: 31558480). While it is a potential therapeutic target for treating metabolic and malignant diseases, current pharmacological agents like bafilomycin A1 are non-selective inhibitors of the entire V-ATPase complex (PubMed: 28257030). Developing subunit-specific inhibitors remains a significant challenge in drug discovery due to the high conservation of V-ATPase components across different tissues. Consequently, targeting the a2 subunit requires strategies that can achieve tissue or isoform specificity to minimize systemic toxicity and adverse effects on global pH homeostasis.

Other names

ATP6V0A2V-type proton ATPase subunit a isoform 2TJ6WSSARCL2ASTV1J6M7Vacuolar proton pump subunit a2V-ATPase a2 subunit

Inhibition of the V-ATPase complex prevents the translocation of protons across the membrane, thereby disrupting the acidification of intracellular compartments such as the Golgi apparatus and lysosomes, which is essential for proper protein processing and degradation.