Probing SWI/SNF remodeling of the nucleosome by unzipping single DNA molecules
UMass Chan Affiliations
Department of Molecular MedicinePetersonCornell University
Graduate School of Biomedical Sciences
Document Type
Journal ArticlePublication Date
2006-05-30Keywords
Chromosomal Proteins, Non-Histone; DNA; Molecular Probes; Nucleosomes; Transcription FactorsLife Sciences
Medicine and Health Sciences
Metadata
Show full item recordAbstract
Chromatin-remodeling enzymes can overcome strong histone-DNA interactions within the nucleosome to regulate access of DNA-binding factors to the genetic code. By unzipping individual DNA duplexes, each containing a uniquely positioned nucleosome flanked by long segments of DNA, we directly probed histone-DNA interactions. The resulting disruption-force signatures were characteristic of the types and locations of interactions and allowed measurement of the positions of nucleosomes with 2.6-base-pair (bp) precision. Nucleosomes remodeled by yeast SWI/SNF were moved bidirectionally along the DNA, resulting in a continuous position distribution. The characteristic distance of motion was approximately 28 bp per remodeling event, and each event occurred with a catalytic efficiency of 0.4 min(-1) per nM SWI/SNF. Remodeled nucleosomes had essentially identical disruption signatures to those of unremodeled nucleosomes, indicating that their overall structure remained canonical. These results impose substantial constraints on the mechanism of SWI/SNF remodeling.Source
Nat Struct Mol Biol. 2006 Jun;13(6):549-54. Epub 2006 May 28. Link to article on publisher's siteDOI
10.1038/nsmb1102Permanent Link to this Item
http://hdl.handle.net/20.500.14038/32551PubMed ID
16732285Related Resources
Link to Article in PubMedae974a485f413a2113503eed53cd6c53
10.1038/nsmb1102