Vacuolar ATPase assembly factor VMA22 (VMA22)

Vacuolar ATPase assembly factor VMA22 (often referred to as CCDC115 in mammals) is an essential assembly chaperone required for the biogenesis of the V-ATPase proton pump complex. VMA22 is localized to the endoplasmic reticulum–Golgi intermediate compartment and is crucial for the stepwise assembly of the membrane-embedded VO region of the V-ATPase, together with two other assembly factors (Vma12 and Vma21)[1][2]. Its primary function is to ensure proper V-ATPase assembly and quality control, preventing premature ATPase activity and acidification in unwanted cellular compartments[1]. Mutations in VMA22/CCDC115 are associated with congenital disorder of glycosylation, type IIo, characterized by impaired lysosomal acidification and related multisystem symptoms[2]. VMA22/CCDC115 also contributes to intracellular iron homeostasis and can influence cell proliferation and death, although it is not part of the mature V-ATPase complex and does not function as an enzyme, receptor, or classical therapeutic target[1][2].

Other names

Vacuolar ATPase assembly protein VMA22CCDC115Coiled-coil domain-containing protein 115CDG2OMGC12981FLJ30131ccp1