Multicolored fluorescent assay for GPCR biased ligands discovery

Here we show a multiplexed assay using multicolored Nomad technology and Endothelin receptor 2 to screen compound libraries. The molecular structure of Nomad Biosensors comprises: a membrane

localization peptide, a second messenger transduction protein binding peptide, a reticulum retention signal and a uorescent peptide. Nomad biosensors are normally localized in the Plasma Membrane

but an increase in the second messenger concentration leads to a change in the structural folding of the Biosensor that promotes its vesicularization. In this assay it is possible to analyze both signals:

calcium and AMPc concentration changes due to the receptor activity, simultaneously. In this work we have used this multiplex assay to screen a library of 480 compounds. Endothelin-1 and BQ-788 were

used as agonist control and antagonist control for this model, respectively. After the screening campaign, positive compounds were chosen for further testing, based on the strength of the initial response

and the lack of cytotoxicity. Our results indicate that this multiplex model is a valid strategy for drug screening.