title: Mechanical disruption of individual nucleosomes reveals a reversible multistage release of DNA.
abstract: The dynamic structure of individual nucleosomes was examined by stretching nucleosomal arrays with a feedback-enhanced optical trap. Forced disassembly of each nucleosome occurred in three stages. Analysis of the data using a simple worm-like chain model yields 76 bp of DNA released from the histone core at low stretching force. Subsequently, 80 bp are released at higher forces in two stages: full extension of DNA with histones bound, followed by detachment of histones. When arrays were relaxed before the dissociated state was reached, nucleosomes were able to reassemble and to repeat the disassembly process. The kinetic parameters for nucleosome disassembly also have been determined.
authors.affiliation: Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853, USA.
authors.forename: Brent D
authors.initials: BD
authors.lastname: Brower-Toland
authors.forename: Corey L
authors.initials: CL
authors.lastname: Smith
authors.forename: Richard C
authors.initials: RC
authors.lastname: Yeh
authors.forename: John T
authors.initials: JT
authors.lastname: Lis
authors.forename: Craig L
authors.initials: CL
authors.lastname: Peterson
authors.forename: Michelle D
authors.initials: MD
authors.lastname: Wang
mesh_terms: D000818:Animals; D001717:Birds; D002843:Chromatin / Q000378:metabolism; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D006657:Histones / Q000737:chemistry; D007700:Kinetics; D008954:Models, Biological; D009707:Nucleosomes / Q000737:chemistry* / Q000378:metabolism; D013997:Time Factors
chemical_list: D002843:Chromatin; D006657:Histones; D009707:Nucleosomes; D004247:DNA