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Dynamics of force-induced DNA slippage

Richard A. Neher·Ulrich Gerland
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Abstract

We study the basepairing dynamics of DNA with repetitive sequences where local strand slippage can create, annihilate, and move bulge loops. Using an explicit theoretical model, we find a rich dynamical behavior as a function of an applied shear force f: reptation-like dynamics at f=f_c with a rupture time scaling as N^3 with its length N, drift-diffusion dynamics for f_c < f < f^*, and a dynamical transition to an unraveling mode of strand separation at f = f^*. We predict a viscoelastic behavior for periodic DNA with time and force scales that can be programmed into its sequence.

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Richard A. Neher, Ulrich Gerland. 2004-09-24. Dynamics of force-induced DNA slippage. https://doi.org/10.1103/physrevlett.93.198102

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