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Open and closed domains in the mouse genome are configured as 10-nm chromatin fibres.

ABSTRACT: The mammalian genome is compacted to fit within the confines of the cell nucleus. DNA is wrapped around nucleosomes, forming the classic "beads-on-a-string" 10-nm chromatin fibre. Ten-nanometre chromatin fibres are thought to condense into 30-nm fibres. This structural reorganization is widely assumed to correspond to transitions between active and repressed chromatin, thereby representing a chief regulatory event. Here, by combining electron spectroscopic imaging with tomography, three-dimensional images are generated, revealing that both open and closed chromatin domains in mouse somatic cells comprise 10-nm fibres. These findings indicate that the 30-nm chromatin model does not reflect the true regulatory structure in vivo.

SUBMITTER: Fussner E

PROVIDER: S-EPMC3492707 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Open and closed domains in the mouse genome are configured as 10-nm chromatin fibres.

Fussner Eden E Strauss Mike M Djuric Ugljesa U Li Ren R Ahmed Kashif K Hart Michael M Ellis James J Bazett-Jones David P DP

EMBO reports 20121101 11

The mammalian genome is compacted to fit within the confines of the cell nucleus. DNA is wrapped around nucleosomes, forming the classic "beads-on-a-string" 10-nm chromatin fibre. Ten-nanometre chromatin fibres are thought to condense into 30-nm fibres. This structural reorganization is widely assumed to correspond to transitions between active and repressed chromatin, thereby representing a chief regulatory event. Here, by combining electron spectroscopic imaging with tomography, three-dimensio ...[more]

PMID: 22986547

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