Fig. 4: The small interface between FZD and G proteins.
From: A framework for Frizzled-G protein coupling and implications to the PCP signaling pathways
a Superposition of the FZD1-Gq, FZD3-Gs and FZD6-Gs structures. b Calculated interface area (Å2) of representative GPCR-G protein complexes in five classes. c Superposition of the FZD1-Gq (green) structure with representative GPCR-G protein structures. Magnified views of α5 helix of G protein are shown in respective dashed boxes with the terminal point of the α5 helix indicated by a blue dashed line. Downward movement of α5 helix in FZD1-Gq structure relative to other GPCR complexes is indicated by the red arrow. Color coding is annotated for each receptor. d The schematic diagram shows the relative position of Gα protein of classical GPCRs (gray) and FZDs (pink). Key interactions between FZD6 and Gs (purple and pink, e), FZD3 and Gs (cyan and orange, f), FZD1 and Gq (green and blue, g). Key residues are shown as sticks. Color coding is annotated for each protein component.
