G-protein-coupled receptor heteromers or how neurons can display differently flavoured patterns in response to the same neurotransmitter

It is becoming accepted that G-protein-coupled receptors (GPCRs) arrange in the neuronal membrane into homo-and hetero-oligomers and, therefore, these complexes mediate neurotransmission. New models are then needed to understand GPCR operation and predict the consequences of GPCR homo-or hetero-oligomerization. Although there is not any unifying theory addressing how hetero-oligomerization occurs, recent models have been devised to understand the thermodynamics of binding of neurotransmitters to GPCRs and the allosteric protomer-protomer interactions involved in neurotransmitter-mediated activation of GPCRs. Although a model to predict how signalling is produced via homo- or hetero-oligomerization is lacking, functional data show that receptor oligomers exist to produce a variety of effects in neurons in response to a single neurotransmitter. British Journal of Pharmacology (2009) 158, 23-31; doi:10.1111/j.1476-5381.2009.00181.x; published online 5 May 2009