Related Experiment Video
Updated: Aug 6, 2026
10:16
Promoter Capture Hi-C: High-resolution, Genome-wide Profiling of Promoter Interactions
Published on: June 28, 2018
Cross-platform Hi-C meta-analysis identifies functional insulators that actively block enhancer-promoter interactions
Jian Cui1, Wanying Xu1,2, Xiuyuan Lang1,2
1Department of Genetics and Genome Sciences, School of Medicine, Case Western Reserve University, Cleveland, OH, USA.
Nature Communications
|July 16, 2026
Summary
Functional Insulators (FINs) dynamically block genome rewiring, challenging the role of static topologically associating domain (TAD) boundaries. These FINs, identified via Hi-C analysis after CTCF/cohesin depletion, are crucial for gene regulation.
Area of Science:
- Genomics
- Molecular Biology
- Epigenetics
Background:
- Topologically associating domain (TAD) boundaries are debated as transcriptional insulators.
- Understanding genome architecture's role in gene regulation is critical.
Purpose of the Study:
- To dynamically define Functional Insulators (FINs) based on their ability to prevent architectural rewiring.
- To investigate the role of CTCF and cohesin in genome insulation and gene activation.
Main Methods:
- Utilized DeepLoop for cross-platform Hi-C data meta-analysis.
- Performed genome-wide mapping of FINs after CTCF or cohesin depletion.
- Conducted multiplexed CTCF-displacement assays to confirm FIN function.
Main Results:
- CTCF depletion induced specific, cohesin-dependent enhancer-promoter loops at G-rich elements.
- These loops drove early-response gene activation.
- FINs were found in active euchromatin, distinct from most TAD boundaries, and sensitive to WAPL.
Conclusions:
- Genome insulation is mediated by dynamic, discrete FINs, not static TAD boundaries.
- FINs play a causal role in localized genome rewiring and gene activation.
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