Statistical models for nucleic acids

TL;DR

This paper uses a 3D mesoscopic Hamiltonian model with path integral techniques to analyze the structural differences between ds-RNA and ds-DNA, explaining their opposite twist-stretch behaviors.

Contribution

It introduces a novel application of path integral methods to model nucleic acid helices and elucidates the structural basis of their twist-stretch differences.

Findings

ds-RNA and ds-DNA have distinct di-nucleotide step structures

The model predicts the average helical repeat for short nucleic acid fragments

Structural features explain the opposite twist-stretch patterns of A- and B-forms

Abstract

ds-RNA and standard ds-DNA show specific structural differences in their di-nucleotide steps, piled along the helical axis. Modeling the helices of short fragments by a 3D mesoscopic Hamiltonian model, I use path integral techniques to compute the average helical repeat and show that these structural features are at the origin of the opposite twist-stretch patterns of the A- and B- form.