Molecular architecture of transcription factor hotspots in early adipogenesis

Cell Rep. 2014 Jun 12;7(5):1434-1442. doi: 10.1016/j.celrep.2014.04.043. Epub 2014 May 22.


Transcription factors have recently been shown to colocalize in hotspot regions of the genome, which are further clustered into super-enhancers. However, the detailed molecular organization of transcription factors at hotspot regions is poorly defined. Here, we have used digital genomic footprinting to precisely define factor localization at a genome-wide level during the early phase of 3T3-L1 adipocyte differentiation, which allows us to obtain detailed molecular insight into how transcription factors target hotspots. We demonstrate the formation of ATF-C/EBP heterodimers at a composite motif on chromatin, and we suggest that this may be a general mechanism for integrating external signals on chromatin. Furthermore, we find evidence of extensive recruitment of transcription factors to hotspots through alternative mechanisms not involving their known motifs and demonstrate that these alternative binding events are functionally important for hotspot formation and activity. Taken together, these findings provide a framework for understanding transcription factor cooperativity in hotspots.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3 Cells
  • Activating Transcription Factors / genetics
  • Activating Transcription Factors / metabolism*
  • Adipogenesis*
  • Animals
  • CCAAT-Enhancer-Binding Proteins / genetics
  • CCAAT-Enhancer-Binding Proteins / metabolism
  • Chromatin / genetics
  • DNA Footprinting
  • Gene Expression Regulation, Developmental
  • Genome
  • Mice
  • Nucleotide Motifs
  • Protein Binding
  • Transcriptional Activation


  • Activating Transcription Factors
  • CCAAT-Enhancer-Binding Proteins
  • Chromatin

Associated data

  • GEO/GSE57415