The budding yeast point centromere associates with two Cse4 molecules during mitosis

Curr Biol. 2013 May 6;23(9):770-4. doi: 10.1016/j.cub.2013.03.042. Epub 2013 Apr 25.

Abstract

The centromere is defined by the incorporation of the centromere-specific histone H3 variant centromere protein A (CENP-A). Like histone H3, CENP-A can form CENP-A-H4 heterotetramers in vitro. However, the in vivo conformation of CENP-A chromatin has been proposed by different studies as hemisomes, canonical, or heterotypic nucleosomes. A clear understanding of the in vivo architecture of CENP-A chromatin is important, because it influences the molecular mechanisms of the assembly and maintenance of the centromere and its function in kinetochore nucleation. A key determinant of this architecture is the number of CENP-A molecules bound to the centromere. Accurate measurement of this number can limit possible centromere architectures. The genetically defined point centromere in the budding yeast Saccharomyces cerevisiae provides a unique opportunity to define this number accurately, as this 120-bp-long centromere can at the most form one nucleosome or hemisome. Using novel live-cell fluorescence microscopy assays, we demonstrate that the budding yeast centromere recruits two Cse4 (ScCENP-A) molecules. These molecules are deposited during S phase and they remain stably bound through late anaphase. Our studies suggest that the budding yeast centromere incorporates a Cse4-H4 tetramer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anaphase
  • Autoantigens / chemistry
  • Autoantigens / genetics
  • Autoantigens / metabolism*
  • Centromere / metabolism*
  • Centromere Protein A
  • Chromatin / metabolism
  • Chromosomal Proteins, Non-Histone / chemistry
  • Chromosomal Proteins, Non-Histone / genetics
  • Chromosomal Proteins, Non-Histone / metabolism*
  • Histones / metabolism
  • Kinetochores / chemistry
  • Kinetochores / metabolism*
  • Microscopy, Fluorescence
  • Mitosis
  • Nucleosomes / genetics
  • Nucleosomes / metabolism*
  • Protein Conformation
  • S Phase
  • Saccharomyces cerevisiae / physiology*
  • Saccharomyces cerevisiae Proteins / chemistry
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*

Substances

  • Autoantigens
  • Centromere Protein A
  • Chromatin
  • Chromosomal Proteins, Non-Histone
  • Histones
  • Nucleosomes
  • Saccharomyces cerevisiae Proteins