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4hn2

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Crystal structure of the catalytic domain of human diphosphoinositol pentakisphosphate kinase 2 (PPIP5K2) in complex with AMPPNP and a substrate analog 5PA-IP5

Structural highlights

4hn2 is a 1 chain structure with sequence from Homo sapiens. This structure supersedes the now removed PDB entry 4gb4. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 1.9Å
Ligands:	, ,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

VIP2_HUMAN Bifunctional inositol kinase that acts in concert with the IP6K kinases IP6K1, IP6K2 and IP6K3 to synthesize the diphosphate group-containing inositol pyrophosphates diphosphoinositol pentakisphosphate, PP-InsP5, and bis-diphosphoinositol tetrakisphosphate, (PP)2-InsP4. PP-InsP5 and (PP)2-InsP4, also respectively called InsP7 and InsP8, regulate a variety of cellular processes, including apoptosis, vesicle trafficking, cytoskeletal dynamics, exocytosis, insulin signaling and neutrophil activation. Phosphorylates inositol hexakisphosphate (InsP6) at positions 1 or 3 to produce PP-InsP5 which is in turn phosphorylated by IP6Ks to produce (PP)2-InsP4. Alternatively, phosphorylates at position 1 or 3 PP-InsP5, produced by IP6Ks from InsP6, to produce (PP)2-InsP4.^[1] ^[2]

Publication Abstract from PubMed

We synthesised analogues of diphosphoinositol polyphosphates (PP-InsPs) in which the diphosphate is replaced by an alpha-phosphonoacetic acid (PA) ester. Structural analysis revealed that 5-PA-InsP(5) mimics 5-PP-InsP(5) binding to the kinase domain of PPIP5K2; both molecules were phosphorylated by the enzyme. PA-InsPs are promising candidates for further studies into the biology of PP-InsPs.

First synthetic analogues of diphosphoinositol polyphosphates: interaction with PP-InsP(5) kinase.,Riley AM, Wang H, Weaver JD, Shears SB, Potter BV Chem Commun (Camb). 2012 Oct 3. PMID:23032903^[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Fridy PC, Otto JC, Dollins DE, York JD. Cloning and characterization of two human VIP1-like inositol hexakisphosphate and diphosphoinositol pentakisphosphate kinases. J Biol Chem. 2007 Oct 19;282(42):30754-62. Epub 2007 Aug 9. PMID:17690096 doi:http://dx.doi.org/M704656200
↑ Choi JH, Williams J, Cho J, Falck JR, Shears SB. Purification, sequencing, and molecular identification of a mammalian PP-InsP5 kinase that is activated when cells are exposed to hyperosmotic stress. J Biol Chem. 2007 Oct 19;282(42):30763-75. Epub 2007 Aug 16. PMID:17702752 doi:http://dx.doi.org/M704655200
↑ Riley AM, Wang H, Weaver JD, Shears SB, Potter BV. First synthetic analogues of diphosphoinositol polyphosphates: interaction with PP-InsP(5) kinase. Chem Commun (Camb). 2012 Oct 3. PMID:23032903 doi:http://dx.doi.org/10.1039/c2cc36044f