This domain is found at the N-terminal end of human Apoptosis -stimulating of p53 protein 2 (ASPP2) and similar sequences mainly from vertebrates. ASPP2 plays a central role in regulation of apoptosis and cell growth via its interactions with proteins such as TP53. This domain shows a mixed twisted beta-sheet and alpha -helices that pack on one side of the beta-sheet, with similarity to a Ras-association (RA) domain [1,2].

1: Solution structure of ASPP2 N-terminal domain (N-ASPP2) reveals a ubiquitin-like fold. Tidow H, Andreeva A, Rutherford TJ, Fersht AR; J Mol Biol. 2007;371:948-958. PMID:17594908

2: iASPP oncoprotein is a key inhibitor of p53 conserved from worm to human. Bergamaschi D, Samuels Y, O'Neil NJ, Trigiante G, Crook T, Hsieh JK, O'Connor DJ, Zhong S, Campargue I, Tomlinson ML, Kuwabara PE, Lu X; Nat Genet. 2003;33:162-167. PMID:12524540