Correa Ana Maria Bernal, Guimarães Jennifer Diniz Soares, Dos Santos E Alhadas Everton, Kushmerick Christopher
Graduate Program in Physiology and Pharmacology, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
Departamento de Fisiologia e Biofísica - ICB, UFMG, Av. Pres. Antônio Carlos, 6627 - Pampulha, Belo Horizonte, MG, 31270-901, Brazil.
Biophys Rev. 2017 Oct;9(5):835-845. doi: 10.1007/s12551-017-0301-7. Epub 2017 Aug 23.
Metabotropic glutamate (mGlu) receptors couple through G proteins to regulate a large number of cell functions. Eight mGlu receptor isoforms have been cloned and classified into three Groups based on sequence, signal transduction mechanisms and pharmacology. This review will focus on Group I mGlu receptors, comprising the isoforms mGlu and mGlu. Activation of these receptors initiates both G protein-dependent and -independent signal transduction pathways. The G-protein-dependent pathway involves mainly Gα, which can activate PLCβ, leading initially to the formation of IP and diacylglycerol. IP can release Ca from cellular stores resulting in activation of Ca-dependent ion channels. Intracellular Ca, together with diacylglycerol, activates PKC, which has many protein targets, including ion channels. Thus, activation of the G-protein-dependent pathway affects cellular excitability though several different effectors. In parallel, G protein-independent pathways lead to activation of non-selective cationic currents and metabotropic synaptic currents and potentials. Here, we provide a survey of the membrane transport proteins responsible for these electrical effects of Group I metabotropic glutamate receptors.
代谢型谷氨酸（mGlu）受体通过G蛋白偶联，以调节大量细胞功能。已克隆出8种mGlu受体亚型，并根据序列、信号转导机制和药理学特性分为3组。本综述将聚焦于I组mGlu受体，包括mGlu和mGlu亚型。这些受体的激活会启动G蛋白依赖性和非依赖性信号转导途径。G蛋白依赖性途径主要涉及Gα，它可激活PLCβ，最初导致IP和二酰基甘油的形成。IP可从细胞内储存中释放Ca，从而激活Ca依赖性离子通道。细胞内Ca与二酰基甘油一起激活PKC，PKC有许多蛋白质靶点，包括离子通道。因此，G蛋白依赖性途径的激活通过几种不同的效应器影响细胞兴奋性。同时，G蛋白非依赖性途径导致非选择性阳离子电流以及代谢型突触电流和电位的激活。在此，我们概述了负责I组代谢型谷氨酸受体这些电效应的膜转运蛋白。
