PathwayStep536 PathwayStep669 PathwayStep665 PathwayStep668 PathwayStep662 PathwayStep663 PathwayStep664 Activation of Protein Kinase C novel isoforms Calcium and Diacylglycerol activate CalDAG-GEFs (RasGRPs) Binding of IP3 to IP3 receptor DAG kinase produces phosphatidic acid from DAG DAG activation of TRPC channels Transport of Ca++ from platelet dense tubular system to cytoplasm Arachidonate production from DAG Effects of PIP2 hydrolysis Edited: Jupe, S, 2009-09-09 Hydrolysis of phosphatidyl inositol-bisphosphate (PIP2) by phospholipase C (PLC) produces diacylglycerol (DAG) and inositol triphosphate (IP3). Both are potent second messengers. IP3 diffuses into the cytosol, but as DAG is a hydrophobic lipid it remains within the plasma membrane. IP3 stimulates the release of calcium ions from the smooth endoplasmic reticulum, while DAG activates the conventional and unconventional protein kinase C (PKC) isoforms, facilitating the translocation of PKC from the cytosol to the plasma membrane. The effects of DAG are mimicked by tumor-promoting phorbol esters. DAG is also a precursor for the biosynthesis of prostaglandins, the endocannabinoid 2-arachidonoylglycerol and an activator of a subfamily of TRP-C (Transient Receptor Potential Canonical) cation channels 3, 6, and 7. Pubmed17157506 Pubmed9601053 Reactome Database ID Release 43114508 Reactome, http://www.reactome.org ReactomeREACT_2202