| Literature DB >> 21855802 |
Sharon E Torigoe1, Debra L Urwin, Haruhiko Ishii, Douglas E Smith, James T Kadonaga.
Abstract
Chromatin assembly involves the combined action of histone chaperones and ATP-dependent motor proteins. Here, we investigate the mechanism of nucleosome assembly with a purified chromatin assembly system containing the histone chaperone NAP1 and the ATP-dependent motor protein ACF. These studies revealed the rapid formation of a stable nonnucleosomal histone-DNA intermediate that is converted into canonical nucleosomes by ACF. The histone-DNA intermediate does not supercoil DNA like a canonical nucleosome, but has a nucleosome-like appearance by atomic force microscopy. This intermediate contains all four core histones, lacks NAP1, and is formed by the initial deposition of histones H3-H4. Conversion of the intermediate into histone H1-containing chromatin results in increased resistance to micrococcal nuclease digestion. These findings suggest that the histone-DNA intermediate corresponds to nascent nucleosome-like structures, such as those observed at DNA replication forks. Related complexes might be formed during other chromatin-directed processes such as transcription, DNA repair, and histone exchange.Entities:
Mesh：
Substances：
Year: 2011 PMID： 21855802 PMCID： PMC3160715 DOI： 10.1016/j.molcel.2011.07.017
Source DB: PubMed Journal: Mol Cell ISSN： 1097-2765 Impact factor: 17.970