Fig. 4.
Structural comparison between SV1 and GHRHR. (A) Comparison between the cryo-EM structures of GHRH–SV1–Gs and GHRH–GHRHR–Gs complexes. Receptors and GHRH are shown in cartoon: GHRHR is colored in green, SV1 in blue, and GHRH in wheat and yellow. Gs is omitted for clarity. (B) Detailed interaction between GHRH (yellow) and the ECD of GHRHR (green). Key residues are shown as sticks. (C) Detailed interaction between GHRH (wheat) and the peptide-binding pocket of SV1 (blue). Salt bridges and hydrogen bonds are shown as dashed lines. (D) Effects of mutations in the peptide-binding pocket of SV1 on cAMP accumulation. Data shown are means ± SEM of four independent experiments (n = 4) conducted in quadruplicate.