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Unzipping of DNA with correlated base-sequence

A. E. Allahverdyan·Zh. S. Gevorkian·Chin-Kun Hu·Ming-Chya Wu
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Abstract

We consider force-induced unzipping transition for a heterogeneous DNA model with a correlated base-sequence. Both finite-range and long-range correlated situations are considered. It is shown that finite-range correlations increase stability of DNA with respect to the external unzipping force. Due to long-range correlations the number of unzipped base-pairs displays two widely different scenarios depending on the details of the base-sequence: either there is no unzipping phase-transition at all, or the transition is realized via a sequence of jumps with magnitude comparable to the size of the system. Both scenarios are different from the behavior of the average number of unzipped base-pairs (non-self-averaging). The results can be relevant for explaining the biological purpose of correlated structures in DNA.

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A. E. Allahverdyan, Zh. S. Gevorkian, Chin-Kun Hu, Ming-Chya Wu. 2004-06-29. Unzipping of DNA with correlated base-sequence. https://doi.org/10.1103/physreve.69.061908

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