Double-stranded RNA bending by AU-tract sequences

Sequence-dependent structural deformations of the DNA double helix (dsDNA) have been extensively studied, where adenine tracts (A-tracts) provide a striking example for global bending in the molecule. However, in contrast to dsDNA, sequence-dependent structural features of dsRNA have received little...

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Bibliographic Details
Authors: Marín-González, Alberto, Aicart-Ramos, Clara, Marin-Baquero, Mikel, Martín González, Alejandro, Vilhena, J.G., Moreno-Herrero, Fernando, Suomalainen, Maarit, Kannan, Abhilash, Greber, Urs F., Pérez Pérez, Rubén
Format: article
Publication Date:2020
Country:España
Institution:Universidad Autónoma de Madrid
Repository:Biblos-e Archivo. Repositorio Institucional de la UAM
Language:English
OAI Identifier:oai:repositorio.uam.es:10486/711174
Online Access:http://hdl.handle.net/10486/711174
https://dx.doi.org/10.1093/nar/gkaa1128
Access Level:Open access
Keyword:Adenine
DNA
Microscopy, Atomic Force
Molecular Dynamics Simulation
Nucleic Acid Conformation
Nucleotide Motifs
RNA, Double-Stranded
Uracil
Física
Description
Summary:Sequence-dependent structural deformations of the DNA double helix (dsDNA) have been extensively studied, where adenine tracts (A-tracts) provide a striking example for global bending in the molecule. However, in contrast to dsDNA, sequence-dependent structural features of dsRNA have received little attention. In this work, we demonstrate that the nucleotide sequence can induce a bend in a canonical Watson-Crick base-paired dsRNA helix. Using all-atom molecular dynamics simulations, we identified a sequence motif consisting of alternating adenines and uracils, or AU-tracts, that strongly bend the RNA double-helix. This finding was experimentally validated using atomic force microscopy imaging of dsRNA molecules designed to display macroscopic curvature via repetitions of phased AU-tract motifs. At the atomic level, this novel phenomenon originates from a localized compression of the dsRNA major groove and a large propeller twist at the position of the AU-tract. Moreover, the magnitude of the bending can be modulated by changing the length of the AU-tract. Altogether, our results demonstrate the possibility of modifying the dsRNA curvature by means of its nucleotide sequence, which may be exploited in the emerging field of RNA nanotechnology and might also constitute a natural mechanism for proteins to achieve recognition of specific dsRNA sequences