Fig. 3

GRK2 is recruited to the activated GLP-1R and this occurs to a different extent by biased agonists. GRK2 recruitment to GLP-1R was measured by nanoBRET in INS1 832/3 GLP-1R KO cells using 100 nM of Exendin-4 (a). AUC of GRK2 recruitment assay by nanoBRET (b), n = 3 independent experiments, each point is an average from 3 to 4 technical replicas (a, b). The same experiment was performed in the presence of 100 nM of different Exendin-4 biased agonists: Ex4-Phe1 (Gαs-biased) and Ex4-Asp3 (β-arrestin biased) (c). AUC of GRK2 recruitment assay by nanoBRET (d). N = 3 independent experiments, each point is an average from 3 to 4 technical replicas. Means ± SEM data are represented, statistical analysis was performed using repeated measures two-way ANOVA (a, c) or paired one-way ANOVA (d) followed by Bonferroni’s post hoc test and paired t test (b), **/^##p < 0.01, ***/^###p < 0.001