First, the intracellular calcium response to histamine was measured in HEK 293 cells using the Fluo-4 Direct™ Calcium Assay. Advanced high resolution cell layer scanning shows a correlation with the calcium signal and cell location in the well. Second, arrestin recruitment through activation of the dopamine D1 receptor with dopamine (D1 agonist) was measured using Tango™ D1-bla U2OS cells and a live cell FRET substrate (LiveBLAzer™). The fluorescent signal generated in the cells by the LiveBLAzer™ substrate greatly benefits from the PHERAstar®'s unique bottom read dual emission detection.
This application note proves the PHERAstar's suitability for GPCR-related drug discovery research that is supported by its direct optic bottom reading; dual emission detection; injection at the point of measurement; high resolution well scanning and orbital averaging.