Fig 1: In vitro activity and binding of KCEM1 at the GLP-1R (A, B), the MC4R (C, D) and activity at the MC5R (E) and MC1R (F). (A) Dose-dependent agonism (% change in FRET ratio tracking levels of cAMP) of Ex-4 and KCEM1 at the GLP-1R. (B) Percent binding average of GLP-1 in the presence of Ex-4 and KCEM1 at the hGLP-1R in competition binding assay. (C) Dose-dependent agonism (cAMP tracking via chemiluminescent signal) of α-MSH and KCEM1 at the hMC4R. (D) Percent binding average of α-MSH and KCEM1 at the hMC4R. (E) Dose-dependent agonism (cAMP tracking via homogeneous time-resolved fluorescence) of NDP-α-MSH and KCEM1 at the MC5R. (F) Dose-dependent agonism (cAMP tracking via homogeneous time resolved fluorescence) of NDP-α-MSH and KCEM1 at the MC1R. KCEM1 also binds the MC3R with a KD of 647 nM (please see supplemental Fig. S1).