InterPro domain: IPR040557

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 alpha-beta-alpha domain [ 1 ]. 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 [ 2 ].

1. Structural basis for an inositol pyrophosphate kinase surmounting phosphate crowding. Nat. Chem. Biol. 8, 111-6
2. Synthetic inositol phosphate analogs reveal that PPIP5K2 has a surface-mounted substrate capture site that is a target for drug discovery. Chem. Biol. 21, 689-99