Quaternary structure predictions and structural communication features of GPCR dimers

In spite of the ever-increasing evidence that G protein-coupled receptors (GPCRs) form dimers/oligomers, the biological role(s) and structural architecture of homologous and heterologous receptor aggregation are, however, far from being clarified. This chapter reviews the insights gained so far, at multiscale levels of resolution, on GPCR dimerization/oligomerization from in vitro experiments, structure predictions, and structure determinations. Focus is put on the achievement by the FiPD-based approach, which proved effective in predicting the supramolecular organization of membrane proteins including GPCRs. The combination of FiPD-based quaternary structure predictions with molecular simulations and analyses can be a valuable tool to infer the effects of dimerization on the structural communication features of a receptor dimer/oligomer bound to functionally different ligands. Ultimately, the integration between atomistic and mesoscopic simulations is expected to be a promising tool to unveil functioning mechanisms that involve intricate protein networks. © 2013 Elsevier Inc.