A phospholipid that is a component of the plasma membrane with signal transduction inducing activity. Phosphatidylinositol 4,5-bisphosphate (PIP2) is an intermediate that can be converted into either the second messenger signaling molecules, inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG), or phosphatidylinositol (3,4,5)-trisphosphate (PtdIns(3,4,5)P3; PIP3). Both PIP2 and PIP3 can act as docking phospholipids, which recruit signaling proteins to the plasma membrane and promotes the activation of several signaling cascades.

Synonyms: 1-Phosphatidyl-D-myo-Inositol 4,5-Bisphosphate Phosphatidylinositol 4,5-Diphosphate PtsIns-4,5-P2 1,2-Diacyl-sn-Glycero-3-Phospho-(1'-myo-Inositol-4',5'-Bisphosphate) 1-O-(3-sn-Phosphatidyl)-1D-myo-Inositol 4,5-Bis(Dihydrogen Phosphate) PtdIns(4,5)P2 Phosphatidyl-myo-Inositol 4,5-Bisphosphate PIPP Phosphatidylinositol 4,5-bisphosphate PIP2 1-Phosphatidyl-1D-myo-Inositol 4,5-Bisphosphate