Standard Article

G Protein-coupled Receptors

  1. Joël Bockaert

Published Online: 15 MAR 2009

DOI: 10.1002/9780470015902.a0000118.pub2



How to Cite

Bockaert, J. 2009. G Protein-coupled Receptors. eLS. .

Author Information

  1. University of Montpellier, CNRS, INSERM, France

Publication History

  1. Published Online: 15 MAR 2009

This is not the most recent version of the article. View current version (15 APR 2014)


Among membrane-bound receptors that recognize regulatory messages (hormones, neurotransmitters, photon, odours, etc.) the seven transmembrane receptors (7 TM) coupled to G proteins (G protein-coupled receptor, GPCRs) are the most numerous. They represent 3% of the total number of genes in human genome. They have similar three-dimensional (3D) structure but can be grouped into 8 classes that share few sequence similarities. GPCRs are targets for more than 50% of the drugs used in therapy.

Key concepts:

  • Cell–cell communication involved messages (hormone, neurotransmitter growth factors, odorant, etc.) and receptors, the majority of them being GPCRs.

  • GPCRs are 7 transmembrane receptors. They form homo- or heterodimers.

  • There are three main classes of GPCRs differing in they primary sequences.

  • The class 3 is the more original one having it binding site within an extra-cellular structure called ‘Venus fly trap’.

  • During evolution mutations have tinkered the GPCR structure in order to allow recognition of ligands as diverse as photon, odorant, sugar, proteins, etc.

  • Virus like human immunodeficiency virus (HIV) virus use GPCRs such as those recognizing chemokines (CCR5, CXCR3) to enter specialized cells such as macrophages or lymphocytes.

  • GPCRs are allosteric molecules and drugs can be developed enhancing or silencing the effect of the natural ligand without having any effect by themselves.

  • Mutations of GPCR are responsible of pathologies. These mutations can render the receptor constitutively active or inactive.


  • signal transduction;
  • receptors;
  • G proteins;
  • hormones;
  • neurotransmitters