FIGURE 5.

C‐tail multisite phosphorylation is crucial for GRK3 recruitment and dissociation. The association of CB1R‐GRK3 in CB1R mutants that interact with GRK3 is increased by SGIP1. HEK293 cells were transiently co‐transfected with the plasmids coding CB1R‐YFP variant + GRK3‐RLuc8 + empty plasmid pRK6/SGIP1‐mCherry (2:1:2 ratio). Cells were stimulated by WIN55212‐2 (WIN, 1 μM). (a) Kinetic profile of GRK3 recruitment to CB1R in the presence and absence of SGIP1. (b) Kinetic profile of GRK3 recruitment to CB1R, CB1R_2A, and CB1R_2A + SGIP1. (c) Kinetic profile of GRK3 recruitment to CB1R and CB1R_6A in the presence or absence of SGIP1. (d) Kinetic profile of GRK3 recruitment to CB1R, CB1R_8A, and CB1R_8A + SGIP1. Data represent the mean ± SEM of three experiments of independent cell preparations performed in three technical replicates. *p ≤ 0.05 (full statistical analysis is disclosed in Tables S4 and S5)