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Probing The Structure And Dynamics Of Nucleosomes Using Atomic Force Microscopy Imaging
Published on: January 31, 2019
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Nanoscale Nucleosome Dynamics Assessed with Time-lapse AFM
1Department of Pharmaceutical Sciences, University of Nebraska Medical Center, 986025, Nebraska Medical Center, Omaha, NE 68198-6025, U. S. A., 402-559-1971 (office), 402-559-9543 (fax).
Biophysical Reviews
|May 20, 2014
Summary
Nucleosomes are dynamic, not static. High-speed atomic force microscopy (HS-AFM) reveals nucleosome dynamics like sliding and unwrapping, offering new insights into chromatin regulation.
Area of Science:
- Molecular Biology
- Biophysics
- Genetics
Background:
- Chromosomal gene regulation hinges on DNA accessibility within nucleosomes.
- Nucleosomes are now understood as dynamic, not static, structures.
- Understanding nucleosome dynamics is crucial for gene regulation insights.
Purpose of the Study:
- To investigate the range and mechanisms of nucleosome dynamics.
- To determine if non-ATP dependent nucleosome unwrapping occurs.
- To identify factors influencing large-scale nucleosome opening and unwrapping.
Main Methods:
- Utilized time-lapse Atomic Force Microscopy (AFM).
- Employed high-speed AFM (HS-AFM) for millisecond-scale molecular dynamics visualization.
- Observed nucleosome dynamics at sub-second time scales.
Main Results:
- Visualized diverse nucleosome dynamics, including sliding and unwrapping.
- Observed complete nucleosome dissociation.
- Provided direct data on the temporal scale of nucleosome movements.
Conclusions:
- Nucleosomes exhibit significant dynamic behaviors beyond static models.
- HS-AFM offers unprecedented views into spontaneous chromatin dynamics.
- Revealed novel mechanisms governing nucleosome opening and unwrapping.
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