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Identification of noncoding transcripts from within CENP-A chromatin at fission yeast centromeres.

ABSTRACT: The histone H3 variant CENP-A is the most favored candidate for an epigenetic mark that specifies the centromere. In fission yeast, adjacent heterochromatin can direct CENP-A(Cnp1) chromatin establishment, but the underlying features governing where CENP-A(Cnp1) chromatin assembles are unknown. We show that, in addition to centromeric regions, a low level of CENP-A(Cnp1) associates with gene promoters where histone H3 is depleted by the activity of the Hrp1(Chd1) chromatin-remodeling factor. Moreover, we demonstrate that noncoding RNAs are transcribed by RNA polymerase II (RNAPII) from CENP-A(Cnp1) chromatin at centromeres. These analyses reveal a similarity between centromeres and a subset of RNAPII genes and suggest a role for remodeling at RNAPII promoters within centromeres that influences the replacement of histone H3 with CENP-A(Cnp1).

SUBMITTER: Choi ES

PROVIDER: S-EPMC3123123 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature

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Identification of noncoding transcripts from within CENP-A chromatin at fission yeast centromeres.

Choi Eun Shik ES Strålfors Annelie A Castillo Araceli G AG Durand-Dubief Mickaël M Ekwall Karl K Allshire Robin C RC

The Journal of biological chemistry 20110428 26

The histone H3 variant CENP-A is the most favored candidate for an epigenetic mark that specifies the centromere. In fission yeast, adjacent heterochromatin can direct CENP-A(Cnp1) chromatin establishment, but the underlying features governing where CENP-A(Cnp1) chromatin assembles are unknown. We show that, in addition to centromeric regions, a low level of CENP-A(Cnp1) associates with gene promoters where histone H3 is depleted by the activity of the Hrp1(Chd1) chromatin-remodeling factor. Mor ...[more]

PMID: 21531710

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