The Phospholipase C family consists of 13 isozymes within six subfamilies, PLC-beta, -gamma, -delta, -epsilon, -zeta, and -eta. PLC-gamma 2 (Phospholipase C gamma-2) contains two SH2 and 1 SH3 domains and is primarily limited to cells of hematopoietic lineage. PLC-gamma 2 is activated by receptor tyrosine kinases in response to growth factors, neurotransmitters, and hormones. Activated PLC-gamma 2 catalyzes the hydrolysis of phosphatidylinositol 4, 5-biphosphate to produce the second messengers inositol 1, 4, 5-triphosphate (IP3) and diacylglycerol (DAG). IP3 mobilizes the release of calcium while DAG activates protein kinase C. PLC-gamma 2 is involved in collagen induced signaling in platelets and antigen-dependent signaling in B-lymphocytes.