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CENP-A confers a reduction in height on octameric nucleosomes.

ABSTRACT: Nucleosomes with histone H3 replaced by CENP-A direct kinetochore assembly. CENP-A nucleosomes from human and Drosophila have been reported to have reduced heights as compared to canonical octameric H3 nucleosomes, thus suggesting a unique tetrameric hemisomal composition. We demonstrate that octameric CENP-A nucleosomes assembled in vitro exhibit reduced heights, indicating that they are physically distinct from H3 nucleosomes and negating the need to invoke the presence of hemisomes.

SUBMITTER: Miell MD

PROVIDER: S-EPMC3676451 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature

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CENP-A confers a reduction in height on octameric nucleosomes.

Miell Matthew D D MD Fuller Colin J CJ Guse Annika A Barysz Helena M HM Downes Andrew A Owen-Hughes Tom T Rappsilber Juri J Straight Aaron F AF Allshire Robin C RC

Nature structural & molecular biology 20130505 6

Nucleosomes with histone H3 replaced by CENP-A direct kinetochore assembly. CENP-A nucleosomes from human and Drosophila have been reported to have reduced heights as compared to canonical octameric H3 nucleosomes, thus suggesting a unique tetrameric hemisomal composition. We demonstrate that octameric CENP-A nucleosomes assembled in vitro exhibit reduced heights, indicating that they are physically distinct from H3 nucleosomes and negating the need to invoke the presence of hemisomes. ...[more]

PMID: 23644598

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