This domain is found at the N terminus of inositol hexakisphosphate and diphosphoinositol-pentakisphosphate kinase 1/2 (VIP1/2, or PPIP5K1/2) and related proteins. Structure analysis of human PPIP5K2 indicate that this region forms α-β-alpha domain []. PPIP5K2 is one of the mammalian PPIP5K isoforms responsible for synthesis of diphosphoinositol polyphosphates (inositol pyrophosphates; PP-InsPs), regulatory molecules that function at the interface of cell signaling and organismic homeostasis [].
