This domain family is found in eukaryotes, and is approximately 50 amino acids in length. The family is found in association with pfam00689, pfam00122, pfam00702, pfam00690. There is a conserved RRFR sequence motif. There are two completely conserved residues (F and W) that may be functionally important. This family is the N terminal autoinhibitory domain of an endosomal Ca2+-ATPase.