New Kinetic Model Explains Force-Induced Rupture of Short DNA Strands
Researchers have developed a master equation framework to model the force-induced rupture of short double-stranded DNA (dsDNA) under shear, accurately reproducing experimental data from DNA-gold nanoparticle constructs. The model incorporates a force-dependent nucleation-zipper pathway with single-base transitions and highlights that the three-dimensional helical geometry of dsDNA is essential for correctly calculating end-to-end distances under shear. The work provides a predictive kinetic foundation for interpreting force-rupture experiments and designing force- and temperature-actuated DNA nanostructures.
A new theoretical study posted to arXiv introduces a master equation framework for modeling shear-induced rupture of short double-stranded DNA (dsDNA), a process relevant to single-molecule biophysics and DNA nanotechnology. The model uses a force-dependent nucleation-zipper pathway with single-base transitions to calculate dissociation rates and transition state distances across a broad force range. When applied to a DNA-gold nanoparticle-DNA construct under constant shear force, the framework accurately reproduces room-temperature experimental data and offers a unified interpretation of prior measurements on similarly sheared duplexes across all force regimes. A key finding is that the three-dimensional helical geometry of dsDNA must be accounted for when defining the end-to-end distance in the rod-like polymer model, a factor previously underappreciated. The study also demonstrates that extracted transition state distances are robust to variations in single-stranded DNA polymer parameters within experimentally relevant ranges. Additionally, the model addresses temperature dependence of rupture, capturing globally-heated dissociation while identifying added complexities introduced by localized plasmonic heating in gold nanoparticle-coupled systems. The authors suggest these results can guide the rational design of DNA nanostructures that respond to mechanical force or temperature stimuli.
What's missing
The model has not yet undergone peer review, as it is a preprint posted to arXiv. The study focuses on constant shear force conditions; its applicability to dynamic or time-varying force regimes is not fully addressed.
What different sources said
- arXiv q-bioCenter
A kinetic model of shear-induced rupture of short dsDNA
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