Fig. 3: The Cryo-EM structure of the FZD3 in complex with Nb9 megabody and BLI data for FZD3 linker peptide interacts with Wnt5a finger-3 peptide.
From: Structural insights into Frizzled3 through nanobody modulators
a The Cryo-EM map of FZD3 in complex with Nb9 Megabody. The extracellular region of FZD3 is coloured in dark grey, TM helices in rainbow, Nb9 in pink, megabody scaffold in cyan, and detergent disc in light grey (transparent surface). b Cartoon representation of the cryo-EM structure. The CRD is placed in the weak density showing a possible orientation with surrounding dashed lines indicating flexibility. c Superposition of a modelled Wnt5a-FZD3 CRD complex (Wnt3_FZD8, PDB 6AHY, was used as the template for modelling) and the FZD3 CRD–Nb8 complex structure (Nb8 coloured in wheat). The Wnt5a finger-3 is coloured orange and FZD3 linker domain is coloured blue. d FZD3 (orange) superimposed with the inactive FZD5 (PDB 6WW2, dark grey) and the active FZD7 (PDB 6EVW, magenta). Only TM5/6 are displayed for clarity. The FZD3 surface is shown for relative TM5/6 location. e Putative small molecule-binding pocket in the FZD3 TMD (grey surface). FZD3 residues that correspond to FZD7 residues proposed to interact with the small molecule F7H are indicated. Numbering of residues according to the Ballesteros-Weinstein scheme is shown in superscript. f BLI sensorgrams for biotinylated Wnt5a finger-3 peptide interacting with the FZD3 linker peptide. g BLI sensorgrams for biotinylated Wnt5a finger-3 peptide interacting with BSA (bovine serum albumin). Different concentrations are shown by coloured lines with indicated concentrations (µM). Fitted curves are shown by black lines.
