Contribution of heteromerization to G protein-coupled receptor function

•Family A GPCRs can function as monomers but they also form higher order complexes.•These complexes are involved in almost every step of the GPCR life cycle.•They are also involved numerous neuropsychiatric conditions.•GPCR heteromers represent novel targets for selective pharmacological treatments.

G protein-coupled receptors (GPCRs) are a remarkably multifaceted family of transmembrane proteins that exert a variety of physiological effects. Although family A GPCRs are able to operate as monomers, there is increasing evidence that heteromerization represents a fundamental aspect of receptor function, trafficking and pharmacology. Most recently, it has been suggested that GPCR heteromers may play a crucial role as new molecular targets of heteromer-selective and bivalent ligands. The current review summarizes key recent developments in these topics.