Phosphatidylinositol-5-Phosphate-4-Kinase Type II Beta (PIP4K2b)

PIP4K2b catalyzes the phosphorylation of phosphatidylinositol-4-phosphate on the fifth hydroxyl of the myo-inositol ring to form phosphatidylinositol-4,5-bisphosphate. This gene is a member of the phosphatidylinositol-4-phosphate 5-kinase family. The encoded protein sequence does not show similarity to other kinases, but the protein does exhibit kinase activity. Additionally, the encoded protein interacts with p55 TNF receptor.

The deduced 416-amino acid protein is 78% identical to PIP5K2A. Using SDS-PAGE, the authors estimated that bacterially expressed PIP5K2B has a molecular mass of 47 kD. Northern blot analysis detected a 6.3-kb PIP5K2B transcript which was abundantly expressed in several human tissues.