Merck, 840046P-5MG, Brain PI(4,5)P2

Although PI(4,5)P2 is a minor component of cell membranes, it plays a critical role as a substrate for a number of important signaling proteins. PI(4,5)P2 is an intermediate in the IP3/DAG pathway where it is hydrolyzed by phospholipase C to liberate the second messengers, inositol 1,4,5-triphosphate (IP3) and diacylglycerol (DAG). PI(4,5)P2 is also a substrate for PI 3-kinase where it is phosphorylated to PI(3,4,5)P3, an activator of downstream signaling components such as the protein kinase AKT.