Establishment of a CaCC-based cell model and method for high-throughput screening of M3 receptor drugs

Abstract

Abstract Muscarinic acetylcholine receptor subtype 3 (M3 receptor) is a G Protein-Coupled Receptor (GPCR) that mediates many important physiological functions. Currently, no M3 receptor drugs with high specificity, high activity, and few side effects have been developed, and there is a lack of methods suitable for high-throughput screening of drugs with GPCRs. In this study, we established an efficient and sensitive drug cell screening model and method for targeting M3 receptors based on calcium-activated chloride channels (CaCCs). This screening model consists of Fischer rat thyroid follicular epithelial (FRT) cells that endogenously express M3 receptors, CaCCs, and the indicator YFP-H148Q/I152L. We verified that the model can sensitively detect changes in intracellular Ca2+ concentration using fluorescence quenching kinetics experiments, confirmed the screening function of the model by applying available M3 receptor drugs, and also evaluated the good performance of the model in high-throughput screening.