This is a family of subunit D form various ATP synthases including V-type H+ transporting and Na+ dependent. Subunit D is suggested to be an integral part of the catalytic sector of the V-ATPase [2].

1: Subunit structure and organization of the genes of the A1A0 ATPase from the Archaeon Methanosarcina mazei Go1. Wilms R, Freiberg C, Wegerle E, Meier I, Mayer F, Muller V; J Biol Chem 1996;271:18843-18852. PMID:8702544

2: A bovine cDNA and a yeast gene (VMA8) encoding the subunit D of the vacuolar H(+)-ATPase. Nelson H, Mandiyan S, Nelson N; Proc Natl Acad Sci U S A 1995;92:497-501. PMID:7831318