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Updated: May 19, 2026
09:52
Probing The Structure And Dynamics Of Nucleosomes Using Atomic Force Microscopy Imaging
Published on: January 31, 2019
Unzipping single DNA molecules to study nucleosome structure and dynamics
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA.
Methods in Enzymology
|August 30, 2012
Summary
DNA unzipping with optical traps offers a powerful single-molecule method to investigate protein-DNA interactions. This guide details practical protocols for nucleosome studies, enabling analysis of structure, dynamics, and remodeling.
Area of Science:
- Biophysics
- Molecular Biology
- Genetics
Background:
- Single-molecule techniques are crucial for understanding complex biological processes.
- Optical trapping provides high-resolution force measurements for biomolecules.
- Nucleosomes are fundamental units of DNA packaging, influencing gene regulation.
Purpose of the Study:
- To provide a comprehensive protocol for DNA unzipping using optical tweezers.
- To demonstrate the application of DNA unzipping in studying nucleosome dynamics.
- To guide researchers in data acquisition, processing, and analysis.
Main Methods:
- Preparation of DNA unzipping templates.
- Construction and calibration of an optical trap instrument.
- Single-molecule force spectroscopy to measure DNA unzipping forces.
- Data acquisition, processing, and analysis pipelines.
Main Results:
- Detailed protocols for DNA unzipping experiments are presented.
- The technique is exemplified through studies on nucleosome structure and dynamics.
- Key findings on nucleosome positioning and remodeling using DNA unzipping are summarized.
Conclusions:
- DNA unzipping with optical tweezers is a versatile and powerful technique.
- This method provides critical insights into protein-DNA interactions at the single-molecule level.
- The presented protocols facilitate the application of DNA unzipping in various biological contexts, particularly nucleosome research.
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