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A cell-free CENP-A assembly system defines the chromatin requirements for centromere maintenance.

ABSTRACT: Centromeres are defined by the presence of CENP-A nucleosomes in chromatin and are essential for accurate chromosome segregation. Centromeric chromatin epigenetically seeds new CENP-A nucleosome formation, thereby maintaining functional centromeres as cells divide. The features within centromeric chromatin that direct new CENP-A assembly remain unclear. Here, we developed a cell-free CENP-A assembly system that enabled the study of chromatin-bound CENP-A and soluble CENP-A separately. We show that two distinct domains of CENP-A within existing CENP-A nucleosomes are required for new CENP-A assembly and that CENP-A nucleosomes recruit the CENP-A assembly factors CENP-C and M18BP1 independently. Furthermore, we demonstrate that the mechanism of CENP-C recruitment to centromeres is dependent on the density of underlying CENP-A nucleosomes.

SUBMITTER: Westhorpe FG

PROVIDER: S-EPMC4477859 | biostudies-literature | 2015 Jun

REPOSITORIES: biostudies-literature

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A cell-free CENP-A assembly system defines the chromatin requirements for centromere maintenance.

Westhorpe Frederick G FG Westhorpe Frederick G FG Fuller Colin J CJ Straight Aaron F AF

The Journal of cell biology 20150615 6

Centromeres are defined by the presence of CENP-A nucleosomes in chromatin and are essential for accurate chromosome segregation. Centromeric chromatin epigenetically seeds new CENP-A nucleosome formation, thereby maintaining functional centromeres as cells divide. The features within centromeric chromatin that direct new CENP-A assembly remain unclear. Here, we developed a cell-free CENP-A assembly system that enabled the study of chromatin-bound CENP-A and soluble CENP-A separately. We show th ...[more]

PMID: 26076692

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