Fig. 1: Structure of LGR4.
From: Structural insights into Wnt/β-catenin signaling regulation by LGR4, R-spondin, and ZNRF3
a Schematic diagrams of the domain organization of human LGR4, RSPO2, and ZNRF3. SP signal peptide, LRR Leucine-rich repeat, LRRNT LRR N-terminal motif, LRRCT LRR C-terminal motif, ECD extracellular domain, TMD transmembrane domain, ICD intracellular domain, Fu furin domain, TSP thrombospondin-like, BR basic amino acid-rich, PAD protease-associated domain, RING RING domain. The regions used in this study are shown below the diagram and the dashed lines represent the unmodeled regions. b Overall structure of human LGR4. The cryo-EM map (left) and ribbon model (right) are shown. LRRNT (salmon pink), 17-LRR (green), LRRCT (salmon pink), connecting segments (yellow), and TMD (blue) are shown in different colors. The gray dashed lines indicate the disordered loop region within the LRRCT. c Structural comparison of the 7-TM structures of LGR4 TMD (blue) and the inactive conformation of LHCGR/LGR2 TMD (pink, PDB: 7FIJ) with the labeled TM numbers. d Close-up view of the ECD-TMD hinge region (dashed rectangle in (b). ECL extracellular Loop, TM Transmembrane helix.
