Activated phosphatidylinositol-specific phospholipase C enzymes catalyze the production of the second messenger molecules diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3) involved in G-protein coupled receptor signaling pathways. PLCB4 is a direct effector of the endothelin receptor signaling pathway that plays an essential role in lower jaw and middle ear structures development (PubMed:35284927).