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Updated: Oct 14, 2025
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A Method to Study de novo Formation of Chromatin Domains
Published on: August 23, 2019
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Structural insights into the interactions of Polycomb Repressive Complex 2 with chromatin
Akhil Gargey Iragavarapu1, Liqi Yao1, Vignesh Kasinath1
1Department of Biochemistry, University of Colorado, Boulder, CO 80303, U.S.A.
Biochemical Society Transactions
|November 8, 2021
Summary
Polycomb repressive complex 2 (PRC2) silences genes by modifying histones. Recent structural studies reveal how cofactor proteins regulate PRC2 recruitment and activity through crosstalk between histone modifications.
Area of Science:
- Epigenetics and Gene Regulation
- Chromatin Biology
- Molecular Mechanisms of Gene Silencing
Background:
- Polycomb repressive complexes (PRCs) are crucial for gene expression regulation and cell identity.
- PRCs function as gene silencers through reversible chemical modifications of histones H3 and H2A.
- Polycomb repressive complex 2 (PRC2) is key in H3K27 trimethylation (H3K27me3), a marker for transcriptional repression.
Purpose of the Study:
- To review recent structural insights into PRC2 regulation.
- To elucidate mechanisms of PRC2 recruitment and activation at target genes.
- To highlight the role of cofactor proteins in PRC2 function.
Main Methods:
- Review of recent structural studies on Polycomb repressive complexes.
- Analysis of mechanisms regulating PRC2 recruitment and activation.
- Investigation of cofactor protein roles in histone modification crosstalk.
Main Results:
- Structural studies reveal cofactor proteins mediate crosstalk between histone modifications.
- Cofactors are critical for recruiting PRC2 to target genes.
- Cofactors stimulate PRC2 methyltransferase activity.
Conclusions:
- Crosstalk between histone modifications, mediated by cofactors, is essential for PRC2 function.
- Understanding these mechanisms provides insight into gene silencing and cell-type identity.
- Recent structural data advances knowledge of PRC2 regulation.
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