Genome-Wide Chromatin Structure Changes During Adipogenesis and Myogenesis

Area of Science:

• Genomics
• Epigenetics
• Cell Biology

Background:

• The spatial organization of the genome, or 3D chromatin structure, is a critical regulator of gene expression.
• Understanding how this architecture changes during cell differentiation processes like adipogenesis and myogenesis is essential.

Purpose of the Study:

• To investigate dynamic changes in 3D chromatin structure and their effect on gene expression during adipogenesis and myogenesis.
• To map the genome-wide 3D chromatin organization in differentiating cell types.

Main Methods:

• Utilized high-throughput chromatin conformation capture (Hi-C) technology.
• Mapped 3D chromatin organization in 3T3-L1 pre-adipocytes/adipocytes and C2C12 myoblasts/myotubes.

Main Results:

• Significant genome-wide compartment A/B rearrangements (~22%) occurred during differentiation, correlating with upregulated gene expression.
• Over half of topologically associating domains (TADs) were dynamic, with specific gene clusters showing altered local interactions.
• Differential chromatin interactions (DCIs), particularly promoter-enhancer interactions (PEIs), were enriched for differentially expressed genes and mediated by key transcription factors.

Conclusions:

• Dynamic 3D genome architecture plays a crucial role in mediating gene expression changes during adipogenesis and myogenesis.
• The study provides a comprehensive resource for understanding long-range chromatin interactions that regulate differentiation-specific gene expression.