Pioneer transcription factors shape the epigenetic landscape

J Biol Chem. 2018 Sep 7;293(36):13795-13804. doi: 10.1074/jbc.R117.001232. Epub 2018 Mar 5.


Pioneer transcription factors have the unique and important role of unmasking chromatin domains during development to allow the implementation of new cellular programs. Compared with those of other transcription factors, this activity implies that pioneer factors can recognize their target DNA sequences in so-called compacted or "closed" heterochromatin and can trigger remodeling of the adjoining chromatin landscape to provide accessibility to nonpioneer transcription factors. Recent studies identified several steps of pioneer action, namely rapid but weak initial binding to heterochromatin and stabilization of binding followed by chromatin opening and loss of cytosine-phosphate-guanine (CpG) methylation that provides epigenetic memory. Whereas CpG demethylation depends on replication, chromatin opening does not. In this Minireview, we highlight the unique properties of this transcription factor class and the challenges of understanding their mechanism of action.

Keywords: DNA demethylation; cell differentiation; chromatin remodeling; development; epigenetics; gene transcription.

Publication types

  • Review

MeSH terms

  • Animals
  • Chromatin / metabolism
  • DNA Methylation
  • Epigenesis, Genetic / physiology*
  • Heterochromatin / metabolism
  • Humans
  • Protein Binding
  • Transcription Factors / physiology*


  • Chromatin
  • Heterochromatin
  • Transcription Factors