Early origin of the bilaterian developmental toolkit

  title={Early origin of the bilaterian developmental toolkit},
  author={Douglas H. Erwin},
  journal={Philosophical Transactions of the Royal Society B: Biological Sciences},
  pages={2253 - 2261}
  • D. Erwin
  • Published 12 August 2009
  • Biology
  • Philosophical Transactions of the Royal Society B: Biological Sciences
Whole-genome sequences from the choanoflagellate Monosiga brevicollis, the placozoan Trichoplax adhaerens and the cnidarian Nematostella vectensis have confirmed results from comparative evolutionary developmental studies that much of the developmental toolkit once thought to be characteristic of bilaterians appeared much earlier in the evolution of animals. The diversity of transcription factors and signalling pathway genes in animals with a limited number of cell types and a restricted… 

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