Phospholipase C (PLC) β and ε enzymes hydrolyze phosphatidylinositol (PI) lipids in response to direct interactions with heterotrimeric G protein subunits and small GTPases, which are activated downstream of G protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs). PI hydrolysis generates second messengers that increase the intracellular Ca²⁺ concentration and activate protein kinase C (PKC), thereby regulating numerous physiological processes. PLCβ and PLCε share a highly conserved core required for lipase activity, but use different strategies and structural elements to autoinhibit basal activity, bind membranes, and engage G protein activators. In this review, we discuss recent structural insights into these enzymes and the implications for how they engage membranes alone or in complex with their G protein regulators.

磷脂酶 C (PLC) β 和 ε 酶水解磷脂酰肌醇 (PI) 脂质，以响应与异源三聚体 G 蛋白亚基和小 GTP 酶的直接相互作用，这些 G 蛋白偶联受体 (GPCR) 和受体酪氨酸激酶 (RTK) 在下游被激活。PI水解产生增加细胞内Ca ^{2+的第二信使}浓度并激活蛋白激酶 C (PKC)，从而调节许多生理过程。PLCβ 和 PLCε 共享脂肪酶活性所需的高度保守的核心，但使用不同的策略和结构元件来自动抑制基础活性、结合膜并接合 G 蛋白激活剂。在这篇综述中，我们讨论了最近对这些酶的结构见解以及它们如何单独或与它们的 G 蛋白调节剂复合地接合膜的影响。