Measuring Protein-Protein Interactions of Melatonin Receptors by Bioluminescence Resonance Energy Transfer (BRET).

The melatonin receptor subfamily belongs to the G protein-coupled receptor superfamily and consists of three members in mammals, MT1, MT2, and GPR50. These receptors can interact with each other to form homo- and heterodimers that are part of larger molecular complexes composed of G proteins, β-arrestins, and other membrane and cytosolic proteins. BRET (bioluminescence resonance energy transfer) is a versatile technique to follow protein-protein interactions on the nanometer scale, in real time, in living cells, which contributed largely to our understanding of the function of melatonin receptors. In this chapter, we describe our BRET protocols for melatonin receptors, which can also be applied to other GPCRs.