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Updated: May 23, 2025
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Stretching Short Sequences of DNA with Constant Force Axial Optical Tweezers
Published on: October 13, 2011
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Multi-plateau force-extension curves of long double-stranded DNA molecules
Alexander Y Afanasyev1, Alexey V Onufriev2,3
1Department of Biomedical Engineering and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
Biorxiv : the Preprint Server for Biology
|March 10, 2025
Summary
Stretched double-stranded DNA (dsDNA) can show multiple plateaus in force-extension curves when composed of segments with different stretching properties. This sequence-dependent behavior may influence DNA processing by cellular machinery.
Area of Science:
- Biophysics
- Molecular Biology
- Computational Biology
Background:
- Double-stranded DNA (dsDNA) exhibits a plateau region in its force-extension curve when highly stretched.
- The mechanical properties of dsDNA are crucial for its biological functions.
Purpose of the Study:
- To predict the force-extension behavior of composite dsDNA fragments with segments of varying plateau forces.
- To investigate the formation of distinct structural states and their potential functional implications.
Main Methods:
- Utilized a bead-spring coarse-grained dynamic model with a non-convex potential.
- Simulated long dsDNA fragments composed of consecutive segments with different plateau force values.
Main Results:
- Predicted multiple distinct plateau regions in force-extension curves for composite dsDNA fragments.
- Observed co-existence of mixed and uniformly stretched DNA states.
- Demonstrated significant differences in segment extension, with sequence order having minimal impact.
Conclusions:
- Composite dsDNA fragments exhibit complex force-extension behaviors with multiple plateau regions.
- Distinct structural states of stretched dsDNA may play a functional role in sequence-dependent DNA processing.
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