Cooperative binding between distant transcription factors is a hallmark of active enhancers

Mol Cell. 2021 Apr 15;81(8):1651-1665.e4. doi: 10.1016/j.molcel.2021.02.014. Epub 2021 Mar 10.

Abstract

Enhancers harbor binding motifs that recruit transcription factors (TFs) for gene activation. While cooperative binding of TFs at enhancers is known to be critical for transcriptional activation of a handful of developmental enhancers, the extent of TF cooperativity genome-wide is unknown. Here, we couple high-resolution nuclease footprinting with single-molecule methylation profiling to characterize TF cooperativity at active enhancers in the Drosophila genome. Enrichment of short micrococcal nuclease (MNase)-protected DNA segments indicates that the majority of enhancers harbor two or more TF-binding sites, and we uncover protected fragments that correspond to co-bound sites in thousands of enhancers. From the analysis of co-binding, we find that cooperativity dominates TF binding in vivo at the majority of active enhancers. Cooperativity is highest between sites spaced 50 bp apart, indicating that cooperativity occurs without apparent protein-protein interactions. Our findings suggest nucleosomes promoting cooperativity because co-binding may effectively clear nucleosomes and promote enhancer function.

Keywords: chromatin dynamics; enhancer; enhancer cooperativity; nucleosome; transcription factor.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Binding Sites / genetics
  • Cell Line
  • Drosophila / genetics
  • Drosophila / metabolism
  • Enhancer Elements, Genetic / genetics*
  • Genome / genetics
  • Micrococcal Nuclease / genetics
  • Nucleosomes / genetics
  • Nucleosomes / metabolism
  • Protein Binding / genetics*
  • Protein Interaction Maps / genetics
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism*
  • Transcriptional Activation / genetics

Substances

  • Nucleosomes
  • Transcription Factors
  • Micrococcal Nuclease