Biology subjects

Sarzynska, J.

Publications and source records attributed to Sarzynska, J..

3 recordsLinked to original sources

bioRxiv2024

Structural and dynamic consequences of inosine, 2'-O-methylation, and N6-methyladenosine modifications in RNA G-quadruplex: A molecular dynamics study

RNA G-quadruplexes (rG4) are stable non-canonical structures, often found to regulate important biological processes such as transcription, translation, splicing, RNA localization, and other steps in gene expression. rG4 structures can also influence DNA-related processes e.g. DNA replication, telomere elongation and homeostasis, and recombination. Due to the involvement of rG4s in such important processes, these structures are potential therapeutic targets against different diseases e.g., viral infection and cancer. Hence, a better understanding of the structure and stability of rG4s and their role in various therapeutically important cellular processes can help in the design of effective therapeutic strategies for targeting such structures. In the present study, we present our findings on the structural and dynamic effect of RNA modifications (inosine; 2'-O-methylation, and m6A-methylation) on RNA G-quadruplex structure from molecular dynamics simulations. Additionally, we also report the dynamic and energetic aspects of inter-quadruplex interactions and the influence of non-G purine tetrads neighboring the inter-quadruplex junction on the interactions.

biophysics↗

bioRxiv2023

Structural and thermodynamic consequences of base pairs containing pseudouridine and N1-methylpseudouridine in RNA duplexes

Pseudouridine ({Psi}) is one of the most common post-transcriptional modifications in RNA and has been known to play significant roles in several crucial biological processes. The N1-methyl derivative of pseudouridine i.e N1-methylpseudouridine has also been reported to be important for the stability and function of RNA. Several studies suggest the importance of pseudouridine and N1-methylpseudouridine in mRNA therapeutics. The critical contribution of pseudouridine, especially that of its N1-methyl derivative in the efficiency of the COVID-19 mRNA vaccines, suggests the requirement to better understand the role of these modifications in the structure, stability and function of RNA. In the present study, we have investigated the consequences of the presence of these modifications in the stability of RNA duplex structures by analyzing different structural properties, hydration characteristics and energetics of these duplexes. We have previously studied the structural and thermodynamic properties of RNA duplexes with an internal {Psi}-A pair and reported the stabilizing effect of {Psi} over U (Deb, I. et al. Sci Rep 9, 16278 (2019)). Here, we have extended our work to understand the properties of RNA duplexes with an internal m1{Psi}-A pair and also theoretically demonstrate the effect of substituting internal U-G, U-U and U-C mismatches with the {Psi}-G, {Psi}-U and {Psi}-C mismatches and also with the m1{Psi}-G, m1{Psi}-U and m1{Psi}-C mismatches respectively, within dsRNA. Our results indicate the context-dependent stabilization of base stacking interactions by N1-methylpseudouridine compared to uridine and pseudouridine, presumably resulting from the increased molecular polarizability due to the presence of the methyl group.

biophysics↗

bioRxiv2021

Structure prediction of the druggable fragments in SARS-CoV-2 untranslated regions

The outbreak of the COVID-19 pandemic has led to intensive studies of both the structure and replication mechanism of SARS-CoV-2. In spite of some secondary structure experiments being carried out, the 3D structure of the key function regions of the viral RNA has not yet been well understood. At the beginning of COVID-19 breakout, RNA-Puzzles community attempted to envisage the three-dimensional structure of 5'- and 3'-Un-Translated Regions (UTRs) of the SARS-CoV-2 genome. Here, we report the results of this prediction challenge, presenting the methodologies developed by six participating groups and discussing 100 RNA 3D models (60 models of 5'-UTR and 40 of 3'-UTR) predicted through applying both human experts and automated server approaches. We describe the original protocol for the reference-free comparative analysis of RNA 3D structures designed especially for this challenge. We elaborate on the deduced consensus structure and the reliability of the predicted structural motifs. All the computationally simulated models, as well as the development and the testing of computational tools dedicated to 3D structure analysis, are available for further study.

bioinformatics↗