Extended Data Figure 7: Effect of guanine nucleotides on [3H]antagonist binding are also seen in competition binding assays.
From: Allosteric coupling from G protein to the agonist-binding pocket in GPCRs

a, Agonist (isoproterenol) competition binding using apyrase-treated β2AR•Gs complexes shows the characteristic G-protein-dependent shift in agonist affinity, along with a dramatic increase in total [3H]DHAP binding, upon the addition of 10 μM GTPγS. b, Normalization of the data from a yields a plot representative of what is commonly reported in the literature. c, Similar to the β2AR, agonist (morphine) competition binding using MOPr•Go complexes shows the characteristic G-protein-dependent shift in agonist affinity, along with a dramatic increase in total [3H]DPN binding, upon the addition of 10 μM GTPγS. d, Normalization of the data from c. All data are shown as mean ± s.e.m. from n = 3 independent experiments performed in duplicate.