The interdependence of mammary-specific super-enhancers and their native promoters facilitates gene activation during pregnancy

Exp Mol Med. 2020 Apr;52(4):682-690. doi: 10.1038/s12276-020-0425-x. Epub 2020 Apr 22.

Abstract

Lineage-specific genetic programs rely on cell-restricted super-enhancers, which are platforms for high-density transcription factor occupation. It is not known whether super-enhancers synergize specifically with their native promoters or provide autonomous and independent regulatory platforms. Here, we investigated the ability of the mammary Wap super-enhancer to activate the promoter of the juxtaposed and ubiquitously expressed Tbrg4 gene in the mouse mammary gland. The Wap super-enhancer was fused, alone or in combination with the Wap promoter, to the Tbrg4 gene. While the super-enhancer increased the expression of the Tbrg4 promoter five-fold, the combination of the super-enhancer and promoter resulted in 80-fold gene upregulation, demonstrating lineage-specific promoter-enhancer synergy. Employing ChIP-seq profiling to determine transcription factor binding and identify activating histone marks, we uncovered a chromatin platform that enables the high-level expression of the native promoter-enhancer but not the heterologous promoter. Taken together, our data reveal that lineage-specific enhancer-promoter synergy is critical for mammary gene regulation during pregnancy and lactation.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Binding Sites
  • Chromatin
  • Chromatin Immunoprecipitation Sequencing
  • Enhancer Elements, Genetic*
  • Female
  • Gene Expression Regulation*
  • Mice
  • Pregnancy
  • Promoter Regions, Genetic*
  • Protein Binding
  • Transcriptional Activation*

Substances

  • Chromatin