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Cohesin organizes chromatin loops at DNA replication factories.

ABSTRACT: Genomic DNA is packed in chromatin fibers organized in higher-order structures within the interphase nucleus. One level of organization involves the formation of chromatin loops that may provide a favorable environment to processes such as DNA replication, transcription, and repair. However, little is known about the mechanistic basis of this structuration. Here we demonstrate that cohesin participates in the spatial organization of DNA replication factories in human cells. Cohesin is enriched at replication origins and interacts with prereplication complex proteins. Down-regulation of cohesin slows down S-phase progression by limiting the number of active origins and increasing the length of chromatin loops that correspond with replicon units. These results give a new dimension to the role of cohesin in the architectural organization of interphase chromatin, by showing its participation in DNA replication.

SUBMITTER: Guillou E

PROVIDER: S-EPMC3003199 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature

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Cohesin organizes chromatin loops at DNA replication factories.

Guillou Emmanuelle E Ibarra Arkaitz A Coulon Vincent V Casado-Vela Juan J Rico Daniel D Casal Ignacio I Schwob Etienne E Losada Ana A Méndez Juan J

Genes & development 20101201 24

Genomic DNA is packed in chromatin fibers organized in higher-order structures within the interphase nucleus. One level of organization involves the formation of chromatin loops that may provide a favorable environment to processes such as DNA replication, transcription, and repair. However, little is known about the mechanistic basis of this structuration. Here we demonstrate that cohesin participates in the spatial organization of DNA replication factories in human cells. Cohesin is enriched a ...[more]

PMID: 21159821

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