GPC3-Unc5 receptor complex structure and role in cell migration

Cell. 2022 Oct 13;185(21):3931-3949.e26. doi: 10.1016/j.cell.2022.09.025.


Neural migration is a critical step during brain development that requires the interactions of cell-surface guidance receptors. Cancer cells often hijack these mechanisms to disseminate. Here, we reveal crystal structures of Uncoordinated-5 receptor D (Unc5D) in complex with morphogen receptor glypican-3 (GPC3), forming an octameric glycoprotein complex. In the complex, four Unc5D molecules pack into an antiparallel bundle, flanked by four GPC3 molecules. Central glycan-glycan interactions are formed by N-linked glycans emanating from GPC3 (N241 in human) and C-mannosylated tryptophans of the Unc5D thrombospondin-like domains. MD simulations, mass spectrometry and structure-based mutants validate the crystallographic data. Anti-GPC3 nanobodies enhance or weaken Unc5-GPC3 binding and, together with mutant proteins, show that Unc5/GPC3 guide migrating pyramidal neurons in the mouse cortex, and cancer cells in an embryonic xenograft neuroblastoma model. The results demonstrate a conserved structural mechanism of cell guidance, where finely balanced Unc5-GPC3 interactions regulate cell migration.

Keywords: GPC3; UNC5A; UNC5B; UNC5C; UNC5D; Unc5; cell guidance; cell migration; cortex development; crystallography; glypican-3; nanobodies; neuroblastoma; stripe assay; structural biology; surface plasmon resonance; uncoordinated-5.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Movement*
  • Glypicans / chemistry*
  • Glypicans / metabolism
  • Humans
  • Mice
  • Mutant Proteins
  • Netrin Receptors / chemistry*
  • Netrin Receptors / metabolism
  • Receptors, Cell Surface / metabolism
  • Single-Domain Antibodies
  • Thrombospondins


  • GPC3 protein, human
  • GPC3 protein, mouse
  • Glypicans
  • Mutant Proteins
  • Netrin Receptors
  • Receptors, Cell Surface
  • Single-Domain Antibodies
  • Thrombospondins
  • Unc5A protein, mouse
  • Unc5b protein, mouse