inositol-tetrakisphosphate 1-kinase; inositol-1,3,4-trisphosphate 5/6-kinase; inositol-triphosphate 5/6-kinase; ins(1,3,4)P(3) 5/6-kinase (ITPK1)

Function: - phosphorylates Ins(1,3,4)P3 & Ins(3,4,5,6)P4 - phosphorylates Ins(3,4,5,6)P4 at position 1 to form Ins(1,3,4,5,6)P5. - phosphorylates Ins(1,3,4)P3 on O-5 and O-6 to form Ins(1,3,4,5,6)P5 - dephosphorylates Ins(1,3,4,5)P4 & Ins(1,3,4,6)P4 to Ins(1,3,4)P3, & Ins(1,3,4,5,6)P5 to Ins(3,4,5,6)P4 - interconverts the inositol tetraphosphateisomers Ins(1,3,4,5)P4 & Ins(1,3,4,6)P4 - rate-limiting enzyme of the InsP6 pathway - modifies TNF-alpha-induced apoptosis by interfering with the activation of TNFRSF1A-associated death domain Cofactor: binds 2 Mg⁺² ions. Structure: - belongs to the ITPK1 family - contains 1 ATP-grasp domain Alternative splicing: named isoforms=2 Expression: - expressed in brain > heart > skeletal muscle = liver > lung - in brain, expressed in cerebellum, cerebral cortex, medulla, spinal cord, occipital lobe, frontal lobe, temporal lobe & putamen

Properties

SIZE: MW = 46 kD entity length = 414 aa MOTIF: binding site SITE: 18-18 FOR-BINDING-OF: inositol 1,3,4-triphosphate ATP-grasp domain SITE: 117-325 MOTIF: ATP-binding site NAME: ATP-binding site SITE: 147-208 binding site SITE: 167-167 FOR-BINDING-OF: inositol 1,3,4-triphosphate binding site SITE: 199-199 FOR-BINDING-OF: inositol 1,3,4-triphosphate Mg+2-binding site SITE: 281-281 Mg+2-binding site SITE: 295-295 Mg+2-binding site SITE: 295-295 Mg+2-binding site SITE: 297-297 binding site SITE: 297-297 FOR-BINDING-OF: inositol 1,3,4-triphosphate

Database Correlations

OMIM 601838 UniProt Q13572 Pfam PF05770 Entrez Gene 3705 Kegg hsa:3705 ENZYME correlations

References

UniProt :accession Q13572