Format

Send to

Choose Destination
Nat Struct Mol Biol. 2013 Jun;20(6):687-95. doi: 10.1038/nsmb.2562. Epub 2013 May 5.

The octamer is the major form of CENP-A nucleosomes at human centromeres.

Author information

1
Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA.

Abstract

The centromere is the chromosomal locus that ensures fidelity in genome transmission at cell division. Centromere protein A (CENP-A) is a histone H3 variant that specifies centromere location independently of DNA sequence. Conflicting evidence has emerged regarding the histone composition and stoichiometry of CENP-A nucleosomes. Here we show that the predominant form of the CENP-A particle at human centromeres is an octameric nucleosome. CENP-A nucleosomes are very highly phased on α-satellite 171-base-pair monomers at normal centromeres and also display strong positioning at neocentromeres. At either type of functional centromere, CENP-A nucleosomes exhibit similar DNA-wrapping behavior, as do octameric CENP-A nucleosomes reconstituted with recombinant components, having looser DNA termini than those on conventional nucleosomes containing canonical histone H3. Thus, the fundamental unit of the chromatin that epigenetically specifies centromere location in mammals is an octameric nucleosome with loose termini.

PMID:
23644596
PMCID:
PMC3760417
DOI:
10.1038/nsmb.2562
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center