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bioRxiv · 10.1101/2022.05.13.491808

Polycomb proteins translate histone methylation to chromatin folding

Lizana, L.·Nahali, N.·Schwartz, Y.
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Abstract

Epigenetic repression often involves covalent histone modifications. Yet, how the presence of a histone mark translates into changes in chromatin structure that ultimately benefit the repression is largely unclear. Polycomb group proteins comprise a family of evolutionarily conserved epigenetic repressors. They act as multi-subunit complexes one of which trimethylates histone H3 at Lysine 27 (H3K27). Here we describe a novel Monte Carlo - Molecular Dynamics simulation framework, which we employed to discover that stochastic interaction of the Polycomb Repressive Complex 1 (PRC1) with tri-methylated H3K27 is sufficient to fold the methylated chromatin. Unexpectedly, such chromatin folding leads to spatial clustering of the DNA elements bound by PRC1.

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Lizana, L., Nahali, N., Schwartz, Y.. 2022-05-13. Polycomb proteins translate histone methylation to chromatin folding. https://doi.org/10.1101/2022.05.13.491808

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