Structures for G-Protein-Coupled Receptor Tetramers in Complex with G Proteins.

G-Protein-coupled receptors (GPCRs) were classically described as monomers. We now appreciate that they also function as homo- and hetero-oligomers, for which structural information is lacking. Here, we use available 3D structures and biochemical considerations to present and evaluate experimentally testable structural models for GPCR oligomers and associated G proteins. [ABSTRACT FROM AUTHOR]