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Updated: Feb 20, 2026
09:20
CRISPR-Mediated Reorganization of Chromatin Loop Structure
Published on: September 14, 2018
13.1K
Recent evidence that TADs and chromatin loops are dynamic structures
Anders S Hansen1,2, Claudia Cattoglio1,2, Xavier Darzacq1
1a Department of Molecular and Cell Biology, Li Ka Shing Center for Biomedical and Health Sciences, CIRM Center of Excellence , University of California , Berkeley , CA , USA.
Nucleus (Austin, Tex.)
|October 28, 2017
Summary
Mammalian genomes fold into Topologically Associating Domains (TADs) and chromatin loops. Recent evidence suggests these structures are dynamic, continually forming and breaking, rather than stable.
Area of Science:
- Genomics
- Molecular Biology
- Biophysics
Background:
- Mammalian genomes are organized into spatial domains that regulate gene expression.
- Topologically Associating Domains (TADs) and chromatin loops are key structural elements involved in enhancer-promoter interactions.
Purpose of the Study:
- To review recent studies on the structure and function of TADs and chromatin loops.
- To discuss the dynamic nature of TADs and chromatin loops.
Main Methods:
- Review of genomic, biochemical, and single-molecule imaging studies.
- Analysis of polymer simulation and Hi-C studies.
- Examination of CTCF and cohesin function in TAD formation.
Main Results:
- Loop extrusion models can explain TAD formation.
- TADs are formed by cohesin and their boundaries are established by CTCF.
- TADs and chromatin loops are dynamic structures that form and break throughout the cell cycle.
Conclusions:
- Evidence argues against stable loops.
- A dynamic model of TADs, which continually form and break, is supported.
- This dynamic model operates throughout the cell cycle.
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