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arXiv · 1711.00741

A nucleobase-centered coarse-grained representation for structure prediction of RNA motifs

Simón Poblete·Sandro Bottaro·Giovanni Bussi
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Abstract

We introduce the SPlit-and-conQueR (SPQR) model, a coarse-grained representation of RNA designed for structure prediction and refinement. In our approach, the representation of a nucleotide consists of a point particle for the phosphate group and an anisotropic particle for the nucleoside. The interactions are, in principle, knowledge-based potentials inspired by the ESCORE function, a base-centered scoring function. However, a special treatment is given to base-pairing interactions and certain geometrical conformations which are lost in a raw knowledge-base model. This results in a representation able to describe planar canonical and non-canonical base pairs and base-phosphate interactions and to distinguish sugar puckers and glycosidic torsion conformations. The model is applied to the folding of several structures, including duplexes with internal loops of non-canonical base pairs, tetraloops, junctions and a pseudoknot. For the majority of these systems, experimental structures are correctly predicted at the level of individual contacts. We also propose a method for efficiently reintroducing atomistic detail from the coarse-grained representation.

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Simón Poblete, Sandro Bottaro, Giovanni Bussi. 2017-11-02. A nucleobase-centered coarse-grained representation for structure prediction of RNA motifs. https://doi.org/10.1093/nar%2Fgkx1269

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