Dorsalization of the neural tube by the non-neural ectoderm

Development. 1995 Jul;121(7):2099-106. doi: 10.1242/dev.121.7.2099.

Abstract

The patterning of cell types along the dorsoventral axis of the spinal cord requires a complex set of inductive signals. While the chordamesoderm is a well-known source of ventralizing signals, relatively little is known about the cues that induce dorsal cell types, including neural crest. Here, we demonstrate that juxtaposition of the non-neural and neural ectoderm is sufficient to induce the expression of dorsal markers, Wnt-1, Wnt-3a and Slug, as well as the formation of neural crest cells. In addition, the competence of neural plate to express Wnt-1 and Wnt-3a appears to be stage dependent, occurring only when neural tissue is taken from stage 8-10 embryos but not from stage 4 embryos, regardless of the age of the non-neural ectoderm. In contrast to the induction of Wnt gene expression, neural crest cell formation and Slug expression can be induced when either stage 4 or stage 8-10 neural plates are placed in contact with the non-neural ectoderm. These data suggest that the non-neural ectoderm provides a signal (or signals) that specifies dorsal cell types within the neural tube, and that the response is dependent on the competence of the neural tissue.

Publication types

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

MeSH terms

  • Animals
  • Central Nervous System / embryology*
  • Chick Embryo
  • Ectoderm / cytology
  • Ectoderm / physiology*
  • Embryonic Induction / genetics
  • Gene Expression
  • In Situ Hybridization
  • Morphogenesis / genetics
  • Protein-Tyrosine Kinases / genetics
  • Proteins / genetics
  • Proto-Oncogene Proteins / genetics
  • Snail Family Transcription Factors
  • Transcription Factors / genetics
  • Wnt Proteins
  • Wnt1 Protein
  • Wnt3 Protein
  • Zebrafish Proteins*
  • Zinc Fingers / genetics

Substances

  • Proteins
  • Proto-Oncogene Proteins
  • Snail Family Transcription Factors
  • Transcription Factors
  • Wnt Proteins
  • Wnt1 Protein
  • Wnt3 Protein
  • Zebrafish Proteins
  • Protein-Tyrosine Kinases