Nanoluc-Based Methods To Measure Beta-Arrestin2 Recruitment To G Protein-Coupled Receptors

Cytosolic beta-arrestins are key regulators of G protein-coupled receptors (GPCRs) by sterically uncoupling G protein activation, facilitating receptor internalization, and/or acting as G protein-independent signaling scaffolds. The current awareness that GPCR ligands may display bias toward G protein signaling or beta-arrestin recruitment makes beta-arrestin recruitment assays important additions to the drug discovery toolbox. This chapter describes two NanoLuc-based methods to monitor beta-arrestin2 recruitment to the human histamine H-1 receptor by measuring bioluminescence resonance energy transfer and enzyme-fragment complementation in real-time on living cells with reasonable high throughput. In addition to the detection of agonism, both assay formats can be used to qualitatively evaluate the binding kinetics of antihistamines on the human histamine H-1 receptor.