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Elastic Correlations in Nucleosomal DNA Structure

Farshid Mohammad-Rafiee·Ramin Golestanian
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Abstract

The structure of DNA in the nucleosome core particle is studied using an elastic model that incorporates anisotropy in the bending energetics and twist-bend coupling. Using the experimentally determined structure of nucleosomal DNA [T.J. Richmond and C.A. Davey, Nature {\bf 423}, 145 (2003)], it is shown that elastic correlations exist between twist, roll, tilt, and stretching of DNA, as well as the distance between phosphate groups. The twist-bend coupling term is shown to be able to capture these correlations to a large extent, and a fit to the experimental data yields a new estimate of G=25 nm for the value of the twist-bend coupling constant.

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Farshid Mohammad-Rafiee, Ramin Golestanian. 2007-01-09. Elastic Correlations in Nucleosomal DNA Structure. https://doi.org/10.1103/physrevlett.94.238102

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