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arXiv · 1102.3313

DNA as a one-dimensional chiral material: Application to the structural transition between B form and Z form

Teruaki Okushima·Hiroshi Kuratsuji
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Abstract

A dynamical model is presented for chiral change in DNA molecules. The model is an extension of the conventional elastic model which incorporates the structure of base pairs and uses a spinor representation for the DNA configuration together with a gauge principle. Motivated by a recent experiment reporting chiral transitions between right-handed B-DNA and left-handed Z-DNA [M. Lee, et. al., Proc. Natl. Acad. Sci. (USA) 107, 4985 (2010)], we analyze the free energy for the particular case of linear DNA with an externally applied torque. The model shows that there exists, at low temperature, a rapid structural change depending on the torque exerted on the DNA, which causes switching in B and Z domain sizes. This can explain the frequent switches of DNA extension observed in experiments.

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Teruaki Okushima, Hiroshi Kuratsuji. 2011-10-05. DNA as a one-dimensional chiral material: Application to the structural transition between B form and Z form. https://doi.org/10.1103/physreve.84.021926

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