Force-dependent elasticity of nucleic acids

• Published in: Nanoscale Vol. 15; no. 14; pp. 6738 - 6744
• Main Authors: Luengo-Márquez, Juan, Zalvide-Pombo, Juan, Pérez, Rubén, Assenza, Salvatore
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 06.04.2023
• Subjects: DNA - chemistry; Elasticity; Mechanical Phenomena; Mechanical properties; Nucleic Acid Conformation; Nucleic Acids; Perturbation; RNA, Double-Stranded
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/d2nr06324g

The functioning of double-stranded (ds) nucleic acids (NAs) in cellular processes is strongly mediated by their elastic response. These processes involve proteins that interact with dsDNA or dsRNA and distort their structures. The perturbation of the elasticity of NAs arising from these deformations is not properly considered by most theoretical frameworks. In this work, we introduce a novel method to assess the impact of mechanical stress on the elastic response of dsDNA and dsRNA through the analysis of the fluctuations of the double helix. Application of this approach to atomistic simulations reveals qualitative differences in the force dependence of the mechanical properties of dsDNA with respect to those of dsRNA, which we relate to structural features of these molecules by means of physically-sound minimalistic models. We present a novel theoretical tool to study stress dependent elasticity from fluctuations. Application to double-stranded nucleic acids reveals that DNA stiffens and RNA softens upon stretching due to a change in the stacking interactions.