Neural crest cells organize the eye via TGF-β and canonical Wnt signalling

Nat Commun. 2011;2:265. doi: 10.1038/ncomms1269.

Abstract

In vertebrates, the lens and retina arise from different embryonic tissues raising the question of how they are aligned to form a functional eye. Neural crest cells are crucial for this process: in their absence, ectopic lenses develop far from the retina. Here we show, using the chick as a model system, that neural crest-derived transforming growth factor-βs activate both Smad3 and canonical Wnt signalling in the adjacent ectoderm to position the lens next to the retina. They do so by controlling Pax6 activity: although Smad3 may inhibit Pax6 protein function, its sustained downregulation requires transcriptional repression by Wnt-initiated β-catenin. We propose that the same neural crest-dependent signalling mechanism is used repeatedly to integrate different components of the eye and suggest a general role for the neural crest in coordinating central and peripheral parts of the sensory nervous system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chick Embryo
  • Chickens
  • Eye / cytology
  • Eye / embryology
  • Eye / metabolism*
  • Lens, Crystalline / embryology
  • Lens, Crystalline / metabolism
  • Models, Biological
  • Neural Crest / cytology
  • Neural Crest / embryology
  • Neural Crest / metabolism*
  • Signal Transduction*
  • Smad3 Protein / genetics
  • Smad3 Protein / metabolism
  • TGF-beta Superfamily Proteins / metabolism*
  • Transforming Growth Factor beta / metabolism
  • Wnt2 Protein / genetics
  • Wnt2 Protein / metabolism*

Substances

  • Smad3 Protein
  • TGF-beta Superfamily Proteins
  • Transforming Growth Factor beta
  • Wnt2 Protein