The fin-to-limb transition as the re-organization of a Turing pattern

Nat Commun. 2016 May 23;7:11582. doi: 10.1038/ncomms11582.


A Turing mechanism implemented by BMP, SOX9 and WNT has been proposed to control mouse digit patterning. However, its generality and contribution to the morphological diversity of fins and limbs has not been explored. Here we provide evidence that the skeletal patterning of the catshark Scyliorhinus canicula pectoral fin is likely driven by a deeply conserved Bmp-Sox9-Wnt Turing network. In catshark fins, the distal nodular elements arise from a periodic spot pattern of Sox9 expression, in contrast to the stripe pattern in mouse digit patterning. However, our computer model shows that the Bmp-Sox9-Wnt network with altered spatial modulation can explain the Sox9 expression in catshark fins. Finally, experimental perturbation of Bmp or Wnt signalling in catshark embryos produces skeletal alterations which match in silico predictions. Together, our results suggest that the broad morphological diversity of the distal fin and limb elements arose from the spatial re-organization of a deeply conserved Turing mechanism.

MeSH terms

  • Animal Fins / embryology*
  • Animal Fins / metabolism
  • Animals
  • Biological Evolution*
  • Bone Morphogenetic Proteins / metabolism
  • Computer Simulation
  • Mice
  • Models, Biological
  • SOX9 Transcription Factor / metabolism*
  • Sharks / embryology*
  • Sharks / metabolism
  • Wnt Proteins / metabolism


  • Bone Morphogenetic Proteins
  • SOX9 Transcription Factor
  • Wnt Proteins