Fig. 3
Human and cat TAS2R43 show different ligand responses and affinities. Cells were transiently transfected with Gα16-gust44 and the indicated receptors human TAS2R38 (H38) TAS2R43 (H43) cat Tas2r38 (C38) and Tas2r43 (C43). 22 hours post-transfection, calcium influx was measured in cells challenged with the ligands characteristic for human TAS2R43. (a & b) Both human and cat Tas2r43 responded to aloin in a dose-dependent manner (individual trace shown for 300 μM); however the cat Tas2r43 EC50 (346 μM) was roughly 10-fold higher than that of human TAS2R43 (35 μM). (c & d) While both human and cat TAS2R43 responded to denatonium, the cat receptor displayed greater sensitivity and a greater than 5-fold lower EC50 (217 μM) than human TAS2R43 (1206 μM). (e) Only human TAS2R43 responded to saccharin