Fig. 2.

Ca²⁺ facilitates G_i3 coupling in negatively charged phosphatidylserine. a The effect of 10 mM CaCl₂ on mB−β₂AR−G protein interaction (G_i3 and G_s) was examined in micelles containing 5:1 DDM:POPS (mole ratio). Data were collected in the absence (APO) and presence (100 μM) of epinephrine. mB−β₂AR concentration is 250 nM. Data are mean ± s.e.m. of three independent experiments. Multiplicity adjusted P values were computed by two-way ANOVA followed by Sidak’s post hoc test between CaCl₂ conditions. b The effect of 10 mM CaCl₂ on mB−β₂AR−G_i3 interaction in DDM micelles ± POPS (i.e. DDM alone vs. 2.5:1 DDM:POPS mole ratio). mB−β₂AR concentration is 250 nM. Data are mean ± s.e.m. of three independent experiments. Multiplicity adjusted P values were computed by three-way ANOVA followed by Sidak’s post hoc test between indicated groups. Source data are provided in the Source Data File