Capture Hi-C Library Generation and Analysis to Detect Chromatin Interactions.

Area of Science:

• Genomics
• Molecular Biology
• Epigenetics

Background:

• Chromosome conformation capture (3C) and Hi-C reveal genome folding and its role in gene regulation, DNA replication, and repair.
• In situ Hi-C improves upon Hi-C by preserving nuclear integrity during processing, reducing artifactual fragment ligations.
• Standard Hi-C requires high-depth sequencing for accurate identification of chromatin contacts.

Purpose of the Study:

• To introduce and detail Capture Hi-C (CHi-C) as an enrichment strategy for Hi-C libraries.
• To demonstrate CHi-C's utility in identifying biologically significant chromatin interactions, particularly with gene promoters.
• To provide protocols for in situ Hi-C and CHi-C library generation and associated bioinformatics analysis.

Main Methods:

• Utilized in situ Hi-C to maintain nuclear integrity during chromatin conformation capture.
• Employed Capture Hi-C (CHi-C) to enrich Hi-C libraries for specific genomic regions, such as gene promoters.
• Developed and described protocols for library preparation and sequencing for both in situ Hi-C and CHi-C.

Main Results:

• CHi-C enables the identification of significant chromatin interactions with greater efficiency than conventional Hi-C for equivalent sequencing depths.
• The method effectively enriches for interactions involving targeted regions, such as gene promoters.
• Genome-wide analysis of chromatin interactions with promoters was successfully performed using CHi-C.

Conclusions:

• CHi-C is a powerful technique for enhancing the discovery of biologically relevant chromatin interactions.
• This method offers a more cost-effective approach to studying 3D genome architecture and its role in gene regulation.
• The described protocols facilitate the application of CHi-C in diverse research settings.