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Updated: Jun 18, 2026
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Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
Double helix crookedness regulates the twist-stretch coupling: A quantitative molecular dynamics analysis
Hai-Long Dong1, Wei-Wei Ju1, Ting Yu2
1College of Physics and Engineering, Henan University of Science and Technology, Luoyang 471023, China.
The Journal of Chemical Physics
|June 17, 2026
Summary
DNA twist-stretch coupling, crucial for biological processes, is regulated by DNA sequence and conformation. Molecular dynamics reveal a non-monotonic relationship between DNA crookedness and twist-stretch coupling, impacting DNA elasticity.
Area of Science:
- Molecular Biology
- Biophysics
- Computational Biology
Background:
- DNA conformation and twist-stretch coupling are vital for biological functions.
- Understanding the relationship between DNA structure and its elastic properties, like twist-stretch coupling, remains a challenge.
Purpose of the Study:
- To investigate how DNA sequence-dependent structural variations influence twist-stretch coupling.
- To elucidate the relationship between DNA conformation and its elastic response to overwinding.
Main Methods:
- Utilized molecular dynamics simulations to model DNA behavior.
- Analyzed sequence-dependent helical structure variations and their impact on twist-stretch coupling.
- Quantified DNA conformation using DNA crookedness (β) and analyzed base-pair parameters.
Main Results:
- Revealed that DNA sequence variations significantly regulate twist-stretch coupling, sometimes causing shortening upon overwinding.
- Identified a non-monotonic relationship between DNA crookedness (β) and the twist-stretch coupling parameter (dL/dN).
- Demonstrated that changes in helical radius, driven by base-pair slide and rise, underlie this structure-elasticity relationship.
Conclusions:
- Established a structure-elasticity framework for double-stranded DNA (dsDNA) twist-stretch coupling.
- Highlighted the critical role of DNA conformation in modulating its mechanical properties.
- Provided quantitative insights into the base-pair level mechanisms governing DNA elasticity.
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