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Updated: May 12, 2026
10:16
Promoter Capture Hi-C: High-resolution, Genome-wide Profiling of Promoter Interactions
Published on: June 28, 2018
An active tissue-specific enhancer and bound transcription factors existing in a precisely positioned nucleosomal
C E McPherson1, E Y Shim, D S Friedman
1Section of Biochemistry, Brown University, Providence, Rhode Island 02912.
Cell
|October 22, 1993
Summary
Certain transcription factors organize nucleosomes to create active enhancers in liver chromatin. This precise nucleosomal arrangement is essential for enhancer function and gene regulation.
Area of Science:
- Molecular Biology
- Genetics
- Chromatin Biology
Background:
- Nucleosomes typically inhibit protein binding and activity at gene promoters.
- Understanding enhancer regulation is crucial for deciphering gene expression control.
Purpose of the Study:
- To investigate the nucleosomal organization of a liver-specific enhancer.
- To determine the relationship between nucleosome positioning and enhancer activity in vivo.
- To elucidate the role of transcription factors in establishing active enhancer structures.
Main Methods:
- Nucleotide-level analysis of chromatin structure in various mouse tissues.
- In vivo footprinting to identify occupied transcription factor-binding sites.
- In vitro chromatin assembly using purified proteins.
Main Results:
- A specific array of three precisely positioned nucleosomes was found only in active liver chromatin.
- Essential transcription factor-binding sites were occupied on nucleosome surfaces, sometimes distorting nucleosome structure.
- An in vitro system replicated this nucleosomal array, dependent on transcription factor binding.
Conclusions:
- Transcription factors can dictate nucleosome organization to define active enhancer elements.
- Precise nucleosome positioning is a key feature of active enhancers.
- This mechanism highlights a novel mode of gene regulation
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