Pax3 and Pax7 interact reciprocally and regulate the expression of cadherin-7 through inducing neuron differentiation in the developing chicken spinal cord

J Comp Neurol. 2016 Apr 1;524(5):940-62. doi: 10.1002/cne.23885. Epub 2015 Sep 9.

Abstract

Pax3 and Pax7 are closely related transcription factors that are widely expressed in the developing nervous system and somites. In the CNS, both genes are expressed in the dorsal part of the neural tube during development. Pax3 and Pax7 are involved in the sonic hedgehog (Shh) signaling pathway and are inhibited by Shh overexpression. The present study confirms in vivo that Pax3 overexpression represses the expression of Pax7, whereas Pax7 overexpression endogenously enhances and ectopically induces the expression of Pax3 in the developing chicken spinal cord. Overexpression of Pax3 and Pax7 represses the endogenous expression of cadherin-7, a member of the cadherin family of morphogenetic genes, and induces its ectopic expression. The present study also shows that overexpression of Pax3 and Pax7 changes the fate and morphology of cells in the neuroepithelial layer and induces the expression of postmitotic neuronal markers. We show that both Pax3 and Pax7 promote the differentiation of neural progenitor cells into neurons. Furthermore, the downregulation of Pax3 and Pax7 with specific shRNAs results in apoptosis in the developing spinal cord. Collectively, these results suggest that the transcription factors Pax3 and Pax7 play important roles in regulating morphogenesis and cell differentiation in the developing spinal cord.

Keywords: Pax3; Pax7; RRID:AB_2531881; RRID:AB_2531882; RRID:AB_528111; RRID:AB_528426; RRID:AB_528428; cadherin-7; expression regulation; spinal cord.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Avian Proteins / biosynthesis*
  • Cadherins / biosynthesis*
  • Cell Differentiation / physiology*
  • Chick Embryo
  • Chickens
  • Gene Expression Regulation, Developmental
  • Mice
  • Neurogenesis / physiology
  • Neurons / metabolism*
  • PAX3 Transcription Factor
  • PAX7 Transcription Factor / metabolism*
  • Paired Box Transcription Factors / metabolism*
  • Protein Binding / physiology
  • Spinal Cord / cytology
  • Spinal Cord / embryology
  • Spinal Cord / metabolism*

Substances

  • Avian Proteins
  • Cad7 protein, Gallus gallus
  • Cadherins
  • PAX3 Transcription Factor
  • PAX3 protein, human
  • PAX7 Transcription Factor
  • PAX7 protein, human
  • Paired Box Transcription Factors