Phospholipase C PLC is an essential enzyme involved in hormone-mediated signaling pathways, particularly in the transduction of extracellular signals into intracellular responses. It plays a crucial role in the regulation of various cellular processes, including cell growth, differentiation, and apoptosis. PLC is activated by a variety of hormones, neurotransmitters, and growth factors, which bind to specific cell surface receptors, such as G protein-coupled receptors GPCRs and receptor tyrosine kinases RTKs .The primary function of PLC in hormone-mediated signaling pathways is to hydrolyze phosphatidylinositol 4,5-bisphosphate PIP2 , a membrane phospholipid, into two second messengers: inositol 1,4,5-trisphosphate IP3 and diacylglycerol DAG . This hydrolysis is initiated when the hormone binds to its specific receptor, leading to the activation of PLC.The two second messengers generated by PLC, IP3 and DAG, have distinct roles in intracellular signaling:1. IP3: IP3 binds to the IP3 receptors located on the endoplasmic reticulum ER membrane, which are calcium channels. The binding of IP3 to these receptors causes the release of calcium ions Ca2+ from the ER into the cytosol. This increase in intracellular calcium concentration acts as a signal for various cellular processes, such as muscle contraction, secretion, and gene expression. The activation of intracellular calcium signaling is essential for the proper functioning of many physiological processes and cellular responses.2. DAG: DAG remains in the plasma membrane and activates protein kinase C PKC , a family of serine/threonine kinases. PKC, in turn, phosphorylates various target proteins, leading to the activation or inhibition of these proteins and modulating various cellular processes, such as cell proliferation, differentiation, and apoptosis.In summary, phospholipase C PLC plays a critical role in hormone-mediated signaling pathways by hydrolyzing PIP2 into IP3 and DAG. This process leads to the activation of intracellular calcium signaling through the release of calcium ions from the ER, as well as the activation of PKC, which modulates various cellular processes. The coordinated action of these signaling molecules allows cells to respond appropriately to extracellular signals, such as hormones, and maintain proper cellular function.