Figure 4.
Gαz-induced activation by the β1AR and β2AR. (a) Schematic representation of the Gαz-Rluc/Gγ1-GFP biosensor used to study the Gαz induced βAR signalling. HEK 293 cells were transfected with Gαz-Rluc, Gγ1-GFP and untagged Gβ1, along with (b,d) β1AR or (c,e) β2AR. Kinetic curves represent time course of Gαz activation by (b) β1AR (vehicle n = 1; isoproterenol n = 2) or (c) β2AR (vehicle and isoproterenol, n = 2) expressed as absolute BRET ratios. Concentration-responses curves for Gαz activation following (d) β1AR or (e) β2AR activation by indicated ligands. Data were normalized to maximal isoproterenol response, which was take as 100%, and are expressed as mean ± SEM values. Details of the number of experiments, maximal responses, pEC50 values and statistical comparisons of curve parameters for (d) β1AR activation by different ligands are provided in Supplementary Tables S1 and S2. For (e) β2AR activation, n = 3 for all ligands.