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arXiv · 1406.0213

Anomalous dynamics of DNA hairpin folding

R. Frederickx·T. in't Veld·E. Carlon
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Abstract

By means of computer simulations of a coarse-grained DNA model we show that the DNA hairpin zippering dynamics is anomalous, i.e. the characteristic time T scales non-linearly with N, the hairpin length: T ~ N^a with a>1. This is in sharp contrast with the prediction of the zipper model for which T ~ N. We show that the anomalous dynamics originates from an increase in the friction during zippering due to the tension built in the closing strands. From a simple polymer model we get a = 1+ nu = 1.59 with nu the Flory exponent, a result which is in agreement with the simulations. We discuss transition path times data where such effects should be detected.

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R. Frederickx, T. in't Veld, E. Carlon. 2014-06-01. Anomalous dynamics of DNA hairpin folding. https://doi.org/10.1103/physrevlett.112.198102

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