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Conformational transformations of DNA macromolecule in heteronomous conformation

P. P. Kanevska·S. N. Volkov
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Abstract

To understand the mechanism of TATA-box conformational transformations we model structure mobility and find the types of conformational excitations of DNA macromolecule in heteronomous conformation. We have constructed the two-component model for describing DNA conformational transformation with simultaneous transitions in the furanos rings of the monomer link. Internal component describes the change of the base pair position in the double helix. External component describes the displacement of mass center of the monomer link. Nonlinearity of the system is accounted with a form of potential energy describing C3'-C2' and C2'-C3' sugars transitions in monomer link, and interrelation between monomer conformational transition and macromolecule deformation. The comparison of our results with experimental data allows to confirm that the localized conformational excitations may realise in DNA TATA-box. These excitations cause the deformation of the macromolecule fragment.

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P. P. Kanevska, S. N. Volkov. 2004-12-15. Conformational transformations of DNA macromolecule in heteronomous conformation. https://arxiv.org/abs/q-bio/0412025

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