Measuring the rapid kinetics of receptor-ligand interactions in live cells using NanoBRET

The importance of receptor-ligand binding kinetics has often been overlooked during drug development, however, over the past decade it has become increasingly clear that a better understanding of the kinetic parameters is crucial for fully evaluating pharmacological effects of a drug. One technique enabling us to measure the real-time kinetics of receptor-ligand interactions in live cells is NanoBRET, which is a bioluminescence resonance energy transfer (BRET)-based assay that uses Nano luciferase. The assay described here allows the measurement of kinetic parameters of a fluorescent ligand and an unlabeled ligand binding to the same place at the receptor, as well as monitoring the effects of another compound like an allosteric modulator on the ligand binding.