Skippen Alison, Swigart Philip, Cockcroft Shamshad
Department of Physiology, University College London, London, UK.
Methods Mol Biol. 2005;312:183-93. doi: 10.1385/1-59259-949-4:183.
Hormones, neurotransmitters, chemoattractants, and growth factors all elicit intracellular responses on binding to cell surface receptors by activating inositol phospholipid-specific phospholipase C (PLC). Activated PLC catalyzes the hydrolysis of phosphatidylinositol bisphosphate (PIP(2)), a minor membrane phospholipid, to form two second messengers, diacylglycerol (DAG) and inositol (1,4,5)trisphosphate [Ins(1,4,5,)P(3)]. DAG is a direct activator of protein kinase C isozymes, and Ins(1,4,5)P(3) mobilizes intracellular Ca(2+). G protein-coupled receptors couple to the PLC-β family via G proteins, and tyrosine kinase receptors activate PLC-γ isozymes. Regardless of the PLC isozyme activated, the product is invariantly Ins(1,4,5)P(3).
激素、神经递质、化学引诱剂和生长因子在与细胞表面受体结合时，均通过激活肌醇磷脂特异性磷脂酶C（PLC）引发细胞内反应。活化的PLC催化磷脂酰肌醇二磷酸（PIP(2)，一种少量的膜磷脂）水解，形成两种第二信使，即二酰基甘油（DAG）和肌醇（1,4,5）三磷酸[Ins(1,4,5)P(3)]。DAG是蛋白激酶C同工酶的直接激活剂，而Ins(1,4,5)P(3)可动员细胞内的Ca(2+)。G蛋白偶联受体通过G蛋白与PLC-β家族偶联，酪氨酸激酶受体则激活PLC-γ同工酶。无论激活的是哪种PLC同工酶，其产物始终是Ins(1,4,5)P(3)。
