McGarrigle Deirdre, Huang Xin-Yun
Department of Physiology, Cornell University Weill Medical College, New York, NY 10021, USA.
Sci STKE. 2007 Jun 26;2007(392):pe35. doi: 10.1126/stke.3922007pe35.
A wide range of extracellular signals are transduced by G protein-coupled receptors (GPCRs). When activated by ligands, GPCRs can activate associated heterotrimeric guanine nucleotide-binding proteins (G proteins), which in turn act on various effectors. Increasing evidence indicates that GPCRs also signal independently of heterotrimeric G proteins. Several GPCRs directly interact with Src-family kinases. Here, we discuss the evidence for direct interaction and activation of Src-family kinases by GPCRs and data that suggest that agonist dosage provides a mechanism by which GPCRs can switch between G protein-dependent and G protein-independent signaling.
多种细胞外信号通过G蛋白偶联受体（GPCRs）进行转导。当被配体激活时，GPCRs可激活相关的异源三聚体鸟嘌呤核苷酸结合蛋白（G蛋白），而G蛋白又作用于各种效应器。越来越多的证据表明，GPCRs也可独立于异源三聚体G蛋白进行信号传导。一些GPCRs直接与Src家族激酶相互作用。在此，我们讨论GPCRs直接与Src家族激酶相互作用并激活它们的证据，以及表明激动剂剂量提供了一种机制，通过该机制GPCRs可在G蛋白依赖性和G蛋白非依赖性信号传导之间切换的数据。
