A high-resolution map of nucleosome positioning on a fission yeast centromere

Genome Res. 2008 Jul;18(7):1064-72. doi: 10.1101/gr.075374.107. Epub 2008 Apr 14.

Abstract

A key element for defining the centromere identity is the incorporation of a specific histone H3, CENPA, known as Cnp1p in Schizosaccharomyces pombe. Previous studies have suggested that functional S. pombe centromeres lack regularly positioned nucleosomes 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 protein genes cnp1, mis18, mis12, nuf2, mal2; overexpression of cnp1; or the deletion of ams2, which encodes a GATA-like factor participating in CENPA incorporation. Bioinformatics analysis of the centromere sequence indicates certain enriched motifs in linker regions between nucleosomes and reveals a sequence bias in nucleosome positioning. In addition, sequence analysis of nucleosome-free regions identifies novel binding sites of Ams2p. We conclude that centromeric nucleosome positions are stable and may be derived from the underlying DNA sequence.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Centromere / genetics*
  • Chromosome Mapping*
  • Chromosomes, Fungal / genetics*
  • DNA, Fungal / analysis
  • DNA, Fungal / genetics
  • Nucleosomes / genetics*
  • Schizosaccharomyces / genetics*

Substances

  • DNA, Fungal
  • Nucleosomes