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Entropic Elasticity, Cooperative Extensibility and Supercoiling Property of DNA: A Unified Viewpoint

Zhou Haijun·Zhang Yang·Ou-Yang Zhong-can
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Abstract

A unified model is constructed to study the recently observed DNA entropic elasticity, cooperative extensibility, and supercoiling property. With the introduction of a new structural parameter (the folding angle $ϕ$), bending deformations of sugar-phosphate backbones, steric effects of nucleotide basepairs, and short-range basestacking interactions are considered. The comprehensive agreement of theoretical results with experimental observations on both torsionally relaxed and negatively supercoiled DNAs strongly indicates that, basestacking interactions, although short-ranged in nature, dominate the elasticity of DNA and hence are of vital biological significance.

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Zhou Haijun, Zhang Yang, Ou-Yang Zhong-can. 1999-04-04. Entropic Elasticity, Cooperative Extensibility and Supercoiling Property of DNA: A Unified Viewpoint. https://arxiv.org/abs/cond-mat/9901321

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