Title
Mechanical disruption of individual nucleosomes reveals a reversible multistage release of DNA
GSBS Program
Biochemistry & Molecular Pharmacology
UMMS Affiliation
Graduate School of Biomedical Sciences; Program in Molecular Medicine; Program in Gene Function and Expression
Date
2-21-2002
Document Type
Article
Medical Subject Headings
Animals; Birds; Chromatin; DNA; Histones; Kinetics; Models, Biological; Nucleosomes; Time Factors
Disciplines
Life Sciences | Medicine and Health Sciences
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.
Rights and Permissions
Citation: Proc Natl Acad Sci U S A. 2002 Feb 19;99(4):1960-5. Link to article on publisher's site