Fig. 5: Functional studies of mutant α_1A-AR and α_1B-AR.

a Representative Ca²⁺ response traces of cells expressing wild-type α_1A-AR in response to different concentrations of A61603. b Representative Ca²⁺ response traces of cells expressing the triple mutant α_1A-AR(V185A, A189S, M292L) in response to different concentrations of A61603 and a saturating concentration of epinephrine. c Dose–response curves for different α_1A-AR constructs in response to A61603. n = 3 independent experiments. Data are presented as mean ± SD. d Representative Ca²⁺ response traces of cells expressing wild-type α_1B-AR in response to different concentrations of A61603 and a saturating concentration of epinephrine. e Representative Ca²⁺ response traces of cells expressing the triple mutant α_1B-AR(A204V, S208A, L314M) in response to different concentrations of A61603. f Dose–response curves for different α_1B-AR constructs in response to A61603. Calcium imaging were analyzed using ImageJ and NIS-Elements Advance Research 5.2.6 software. Each single cell was manually selected as region of interest and the fluorescence intensity was normalized to the baseline before agonist application. An average trace (60-200 cells per recording) was used to quantify maximum fluorescence amplitude after drug application. n = 3 independent experiments. Data are presented as mean ± SD. Dose–response curve was done using nonlinear fit in GraphPad Prism.