Class C GPCR

The class C G-protein-coupled receptors (InterPro: IPR000337) are a class of G-protein coupled receptors that include the metabotropic glutamate receptors (InterPro: IPR000162) and several additional receptors.^[1]

Structurally they are composed of four elements; an N-terminal signal sequence; a large hydrophilic extracellular agonist-binding region containing several conserved cysteine residues which could be involved in disulphide bonds; a shorter region containing seven transmembrane domains; and a C-terminal cytoplasmic domain of variable length.^[1] This protein family includes metabotropic glutamate receptors, the extracellular calcium-sensing receptors, the gamma-amino-butyric acid (GABA) type B receptors, and the vomeronasal type-2 receptors.