CATH Classification

Domain Context

CATH Clusters

Superfamily 3.40.50.11370
Functional Family Inositol-tetrakisphosphate 1-kinase

Enzyme Information

2.7.1.134
Inositol-tetrakisphosphate 1-kinase.
based on mapping to UniProt Q13572
ATP + 1D-myo-inositol 3,4,5,6-tetrakisphosphate = ADP + 1D-myo-inositol 1,3,4,5,6-pentakisphosphate.
-!- This enzyme also phosphorylates Ins(1,3,4)P(3) on O-5 and O-6. -!- The phosphotransfer from ATP to either inositol 1,3,4-trisphosphate or inositol 3,4,5,6-tetrakisphosphate appears to be freely reversible to the extent that the enzyme can act like an inositol polyphosphate phosphatase in the presence of ADP. -!- It can also catalyze an isomerization between Ins(1,3,4,5)P(4) and Ins(1,3,4,6)P(4) in the presence of ADP. -!- Formerly EC 2.7.1.133 and EC 2.7.1.139.
2.7.1.159
Inositol-1,3,4-trisphosphate 5/6-kinase.
based on mapping to UniProt Q13572
(1) ATP + 1D-myo-inositol 1,3,4-trisphosphate = ADP + 1D-myo-inositol 1,3,4,5-tetrakisphosphate. (2) ATP + 1D-myo-inositol 1,3,4-trisphosphate = ADP + 1D-myo-inositol 1,3,4,6-tetrakisphosphate.
-!- In humans, this enzyme, along with EC 2.7.1.127, EC 2.7.1.140 and EC 2.7.1.158 is involved in the production of inositol hexakisphosphate (InsP(6)). -!- InsP(6) is involved in many cellular processes, including mRNA export from the nucleus. -!- Yeast do not have this enzyme, so produce InsP(6) from Ins(1,4,5)P(3) by the actions of EC 2.7.1.151 and EC 2.7.1.158.

UniProtKB Entries (1)

Q13572
ITPK1_HUMAN
Homo sapiens
Inositol-tetrakisphosphate 1-kinase

PDB Structure

PDB 2ODT
External Links
Method X-RAY DIFFRACTION
Organism Escherichia
Primary Citation
Structure of human Inositol 1,3,4-trisphosphate 5/6-kinase
Busam, R.D., Arrowsmith, C., Berglund, H., Collins, R., Edwards, A., Ericsson, U.B., Flodin, S., Flores, A., Hammarstrom, M., Holmberg, S.L., Johansson, I., Karlberg, T., Kotenyova, T., Moche, M., Nilsson, M.E., Nordlund, P., Nyman, T., Ogg, D., Sagemark, J., Sundstrom, M., Uppenberg, J., Van Den Berg, S., Weigelt, J., Persson, C., Thorsell, A.G., Hallberg, B.M.
To be Published