Bockaert J, Pin J P
UPR CNRS 9023, CCIPE, 141 rue de la Cardonille, 34094 Montpellier Cedex 5, France.
EMBO J. 1999 Apr 1;18(7):1723-9. doi: 10.1093/emboj/18.7.1723.
Among membrane-bound receptors, the G protein-coupled receptors (GPCRs) are certainly the most diverse. They have been very successful during evolution, being capable of transducing messages as different as photons, organic odorants, nucleotides, nucleosides, peptides, lipids and proteins. Indirect studies, as well as two-dimensional crystallization of rhodopsin, have led to a useful model of a common 'central core', composed of seven transmembrane helical domains, and its structural modifications during activation. There are at least six families of GPCRs showing no sequence similarity. They use an amazing number of different domains both to bind their ligands and to activate G proteins. The fine-tuning of their coupling to G proteins is regulated by splicing, RNA editing and phosphorylation. Some GPCRs have been found to form either homo- or heterodimers with a structurally different GPCR, but also with membrane-bound proteins having one transmembrane domain such as nina-A, odr-4 or RAMP, the latter being involved in their targeting, function and pharmacology. Finally, some GPCRs are unfaithful to G proteins and interact directly, via their C-terminal domain, with proteins containing PDZ and Enabled/VASP homology (EVH)-like domains.
在膜结合受体中，G蛋白偶联受体（GPCRs）无疑是种类最多的。它们在进化过程中非常成功，能够转导各种不同的信号，如光子、有机气味分子、核苷酸、核苷、肽、脂质和蛋白质。间接研究以及视紫红质的二维结晶，已得出一个有用的模型，即由七个跨膜螺旋结构域组成的共同“中央核心”及其激活过程中的结构修饰。至少有六个GPCR家族，它们之间没有序列相似性。它们使用大量不同的结构域来结合配体并激活G蛋白。它们与G蛋白偶联的微调受剪接、RNA编辑和磷酸化调节。已发现一些GPCR可与结构不同的GPCR形成同二聚体或异二聚体，也可与具有一个跨膜结构域的膜结合蛋白形成二聚体，如nina - A、odr - 4或RAMP，后者参与其靶向、功能和药理学。最后，一些GPCR对G蛋白不专一，而是通过其C末端结构域直接与含有PDZ和Enabled/VASP同源（EVH）样结构域的蛋白质相互作用。
