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E-GEOD-10742 - Nucleosome Mapping in S. pombe Centromeres

Status
Submitted on 6 March 2008, released on 30 May 2008, last updated on 1 May 2014
Organism
Schizosaccharomyces pombe
Samples (32)
Arrays (2)
Protocols (7)
Description
A key element for defining the centromere identity is the incorporation of a specific histone H3, CENP-A, known as Cnp1p in S. pombe. Previous studies have suggested that functional S. pombe centromeres lack nucleosome arrays and may involve chromatin remodeling as a key step of kinetochore assembly. We used tiling microarrays to show that nucleosomes are in fact positioned in regular intervals in the core of centromere 2, providing the first high resolution map of regional centromere chromatin. Nucleosome locations are not disrupted by mutations in kinetochore proteins cnp1, mis18, mis12, nuf2, mal2, overexpression of Cnp1p, or deletion of ams2. Bioinformatic analysis of the centromere sequence indicates certain enriched motifs in linker regions between nucleosomes and reveals a sequence-bias in nucleosome positioning. We conclude that centromeric nucleosome positions are stable and may be derived from the underlying DNA sequence. In addition, sequence analysis of nucleosome-free regions identifies novel binding sites for the GATA-like protein Ams2p, which participates in CENP-A incorporation. Keywords: Nucleosome Mapping Study Entire cnt regions and histone-related genes were tiled at 1-5 bp spacing using 60-mer probes.
Experiment type
ChIP-chip by tiling array 
Contacts
Jun S Song, X.Shirley Liu, Xiangwei He, Xingkun Liu
Citation
MIAME
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