In and out: histone variant exchange in chromatin.

Stowers Institute for Medical Research, 1000 East 50th Street, Kansas City, MO 64110, USA.
Trends in Biochemical Sciences (Impact Factor: 13.52). 01/2006; 30(12):680-7. DOI: 10.1016/j.tibs.2005.10.003
Source: PubMed

ABSTRACT Alterations in nucleosome structure affect the accessibility of the DNA and can generate specialized domains of chromatin in the genome. Such changes can be introduced by posttranslational modifications of histones, by chromatin remodeling, or by the incorporation of variants of H2A and H3 into nucleosomes. In contrast to the canonical histones, which are deposited behind the replication fork during S phase, histone variants are incorporated in a process that is independent of DNA replication. Recent studies have shown that distinct multiprotein complexes are responsible for the targeted deposition of histone variants at active genes, centromeres and silent loci. The incorporation of histone variants most probably has epigenetic consequences and contributes to architectural changes in chromosomes.

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