This is the N-terminal domain found in the Inositol hexakisphosphate and diphosphoinositol-pentakisphosphate kinase 2 (PPIP5K2), EC:2.7.4.24. 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 [3].

1: Structural basis for an inositol pyrophosphate kinase surmounting phosphate crowding. Wang H, Falck JR, Hall TM, Shears SB; Nat Chem Biol. 2011;8:111-116. PMID:22119861

2: First synthetic analogues of diphosphoinositol polyphosphates: interaction with PP-InsP5 kinase. Riley AM, Wang H, Weaver JD, Shears SB, Potter BV; Chem Commun (Camb). 2012;48:11292-11294. PMID:23032903

3: Synthetic inositol phosphate analogs reveal that PPIP5K2 has a surface-mounted substrate capture site that is a target for drug discovery. Wang H, Godage HY, Riley AM, Weaver JD, Shears SB, Potter BV; Chem Biol. 2014;21:689-699. PMID:24768307

4: Synthesis of densely phosphorylated bis-1,5-diphospho-myo-inositol tetrakisphosphate and its enantiomer by bidirectional P-anhydride formation. Capolicchio S, Wang H, Thakor DT, Shears SB, Jessen HJ; Angew Chem Int Ed Engl. 2014;53:9508-9511. PMID:25044992