Diacylglycerol

Diacylglycerol (DAG) is molecule which is bound to the inner layer of the phoslipid bilayer in eukaryotic cells by two transmembrane fatty acid tails. DAG is activated when the IP (Inositol-Phospholipid) signalling pathway is activated by a GPCR (G Protein Coupled Recptor) binding. The PI pathway activates PLC-β (phospholipase C) which catalyses the reaction whereby PIP₂ (phosphotitylinositol-4,5-bisphosphate) is cleaved to form the free molecule IP₃ (Inositol-1,4,5-trisphosphate) and DAG. From this DAG is then able to interact further in the cell signalling pathway by activating PKC (Ca2+ dependent Protein Kinase), which is a kinase involved in an intercellular phosphorylation cascade.