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arXiv · 2408.07415

Polymeric Properties of Higher-Order G-Quadruplex Telomeric Structures: Effects of Chemically Inert Crowders

Deniz Mostarac·Mattia Trapella·Luca Bertini·Lucia Comez·Alessandro Paciaroni·Cristiano De Michele
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Abstract

G-quadruplexes are non-canonical DNA structures rather ubiquitous in human genome, which are thought to play a crucial role in the development of 85-90 % of cancers. Here, we present a novel coarse-grained approach in modeling G-quadruplexes which accounts for their structural flexibility. We apply it to study the polymeric properties of G-quadruplex multimers, with and without crowder particles, to mimic in-vivo conditions. We find that, contrary to some suggestions found in the literature, long G-quadruplex multimers are rather flexible polymeric macromolecules, with a local persistence length comparable to monomer size, exhibiting chain stiffness variation profile consistent with a real polymer in good solvent. Moreover, in a crowded environment (up to 10% volume fraction), we report that G-quadruplex multimers exhibit an increased propensity for coiling, with a corresponding decrease in the measured chain stiffness. Accurately accounting for the polymeric properties of G4 multimers is crucial for understanding their interactions with anticancer G4-targeting drugs, thereby significantly enhancing the design and effectiveness of these drugs.

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Deniz Mostarac, Mattia Trapella, Luca Bertini, Lucia Comez, Alessandro Paciaroni, Cristiano De Michele. 2024-08-14. Polymeric Properties of Higher-Order G-Quadruplex Telomeric Structures: Effects of Chemically Inert Crowders. https://arxiv.org/abs/2408.07415

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