InterPro domain: IPR019013

The vacuolar ATPase assembly integral membrane protein Vma21 is required for the assembly of the integral membrane sector (V0 component) of the vacuolar ATPase (V-ATPase) in the endoplasmic reticulum [ 1 ]. Mutations in the human VMA32 gene cause X-linked myopathy with excessive autophagy (XMEA), which is a childhood-onset disease characterised by progressive vacuolation and atrophy of skeletal muscle [ 2 ].

1. Role of Vma21p in assembly and transport of the yeast vacuolar ATPase. Mol. Biol. Cell 15, 5075-91
2. VMA21 deficiency causes an autophagic myopathy by compromising V-ATPase activity and lysosomal acidification. Cell 137, 235-46