Lineage specific transcription factors and epigenetic regulators mediate TGFβ-dependent enhancer activation

Nucleic Acids Res. 2018 Apr 20;46(7):3351-3365. doi: 10.1093/nar/gky093.

Abstract

During neurogenesis, dynamic developmental cues, transcription factors and histone modifying enzymes regulate the gene expression programs by modulating the activity of neural-specific enhancers. How transient developmental signals coordinate transcription factor recruitment to enhancers and to which extent chromatin modifiers contribute to enhancer activity is starting to be uncovered. Here, we take advantage of neural stem cells as a model to unravel the mechanisms underlying neural enhancer activation in response to the TGFβ signaling. Genome-wide experiments demonstrate that the proneural factor ASCL1 assists SMAD3 in the binding to a subset of enhancers. Once located at the enhancers, SMAD3 recruits the histone demethylase JMJD3 and the remodeling factor CHD8, creating the appropriate chromatin landscape to allow enhancer transcription and posterior gene activation. Finally, to analyze the phenotypical traits owed to cis-regulatory regions, we use CRISPR-Cas9 technology to demonstrate that the TGFβ-responsive Neurog2 enhancer is essential for proper neuronal polarization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Basic Helix-Loop-Helix Transcription Factors / genetics*
  • CRISPR-Cas Systems / genetics
  • Cell Lineage / genetics
  • Cell Polarity / genetics
  • DNA-Binding Proteins / genetics
  • Enhancer Elements, Genetic / genetics*
  • Epigenesis, Genetic
  • Jumonji Domain-Containing Histone Demethylases / genetics
  • Mice
  • Nerve Tissue Proteins / genetics
  • Neural Stem Cells / metabolism
  • Neurogenesis / genetics*
  • Promoter Regions, Genetic
  • Signal Transduction / genetics
  • Smad3 Protein / genetics*
  • Transcription Factors / genetics
  • Transforming Growth Factor beta / genetics*

Substances

  • ASCL1 protein, human
  • Basic Helix-Loop-Helix Transcription Factors
  • CHD8 protein, human
  • DNA-Binding Proteins
  • NEUROG2 protein, human
  • Nerve Tissue Proteins
  • SMAD3 protein, human
  • Smad3 Protein
  • Transcription Factors
  • Transforming Growth Factor beta
  • Jumonji Domain-Containing Histone Demethylases
  • KDM6B protein, human