Fig. 5: ICL2 preferentially contributes to Gq signaling.
From: Insights into G-protein coupling preference from cryo-EM structures of Gq-bound PTH1R
a, Conformational differences between Gq-bound and Gs-bound PTH1R around ICL2. b,c. Interactions between the TM4 side of ICL2 and the G protein in Gq (b) and Gs (c). Residues potentially engaged in ionic interactions are shown as stick models. d,e. Interactions between the TM3 side of ICL2 and the G protein in Gq (d) and Gs (e). Notable residues are shown as stick and CPK models. f, Gq and Gs coupling activities of the PTH1R mutants. PTH-induced Gq and Gs responses were analyzed by the NanoBiT G-protein dissociation assay. Bars and error bars represent the mean and s.e.m., respectively, from 3–6 independent experiments. The exact sample sizes are provided in Supplementary Table 3. Statistical analysis was performed using a two-way ANOVA, followed by Šidák’s post hoc test (NS, P > 0.05; *P < 0.05, **P < 0.01 and ***P < 0.001). g,h, Schematic representation of the G-protein coupling preference for Gq (g) and Gs (h).
