Fig. 5: Interactions of OTR and Gαo/q.
From: Structural basis for the activation and ligand recognition of the human oxytocin receptor
a Detailed interactions of Gq α5 with OTR. b Structural comparison of OTR:Go/q to Gs/q complexes with focus on Gq α5 positioning: NK1R:Gs/q (purple, PDB 7P00), OX2R:Gs/q (green, PDB 7L1U), and CCK1R:Gs/q (yellow, PDB 7MBY). c Structural superposition of OTR with α1AR:Go (green; PDB ID: 6K41), CCR6:Go (purple; PDB ID: 6WWZ), and M2R:Go (yellow; PDB ID: 6OIK) as viewed from the intracellular side with a focus on receptor – G protein interaction. Arrows indicate structural differences between intracellular receptor helix tips and α5 orientations. d Schematic drawing of direct interactions between OTR and the α5 helix of Gαo/q. Hydrogen bonds are drawn as dashed lines. Salt bridges are indicated by lines coloured in red. Amino acids are coloured according to their biophysical properties. e Structural superposition of OTR-bound Go/q with Gs/q from different signalling complexes: NK1R:Gs/q (purple; PDB ID: 7P00), OX2R:Gs/q (green; PDB ID: 7L1U), and CCK1R:Gs/q (yellow, PDB ID: 7MBY) with two different close-up views on Gα5. f Structural comparison of OTR:Go/q and V2R:Gs (pink, PDB 7KH0) with focus on helix α5 positioning.
