Figure 7. Functional profiles of selected MOR-D₃R hybrids.

Each panel shows a different signaling readout: A. Nb33 recruitment at MOR, B. MOR-mediated Gα_i2 protein activation, C. Antagonism at MOR using GPA in the presence of 100 nM of DAMGO, D. Arrestin-3 recruitment at MOR in the presence of overexpressed GRK2, E. D₃R-mediated Gα_oA protein activation and F. Antagonism at D₃R using GPA in the presence of 3 nM of quinpirole. In order to ensure that test ligands achieved maximal receptor occupancy possible before agonist addition, all ligands were added to the cells 3h prior to activating D₃R with quinpirole and measuring BRET signals with the exception of 5. Dotted lines represent fits where the bottom asymptote was constrained to be 0%.