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Polycomb-mediated chromatin loops revealed by a subkilobase-resolution chromatin interaction map.

ABSTRACT: The locations of chromatin loops in Drosophila were determined by Hi-C (chemical cross-linking, restriction digestion, ligation, and high-throughput DNA sequencing). Whereas most loop boundaries or "anchors" are associated with CTCF protein in mammals, loop anchors in Drosophila were found most often in association with the polycomb group (PcG) protein Polycomb (Pc), a subunit of polycomb repressive complex 1 (PRC1). Loops were frequently located within domains of PcG-repressed chromatin. Promoters located at PRC1 loop anchors regulate some of the most important developmental genes and are less likely to be expressed than those not at PRC1 loop anchors. Although DNA looping has most commonly been associated with enhancer-promoter communication, our results indicate that loops are also associated with gene repression.

SUBMITTER: Eagen KP

PROVIDER: S-EPMC5565414 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Polycomb-mediated chromatin loops revealed by a subkilobase-resolution chromatin interaction map.

Eagen Kyle P KP Aiden Erez Lieberman EL Kornberg Roger D RD

Proceedings of the National Academy of Sciences of the United States of America 20170801 33

The locations of chromatin loops in <i>Drosophila</i> were determined by Hi-C (chemical cross-linking, restriction digestion, ligation, and high-throughput DNA sequencing). Whereas most loop boundaries or "anchors" are associated with CTCF protein in mammals, loop anchors in <i>Drosophila</i> were found most often in association with the polycomb group (PcG) protein Polycomb (Pc), a subunit of polycomb repressive complex 1 (PRC1). Loops were frequently located within domains of PcG-repressed chr ...[more]

PMID: 28765367

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