Complexity of Guanine Quadruplex Unfolding Pathways Revealed by Atomistic Pulling Simulations.

ABSTRACT: Guanine quadruplexes (GQs) are non-canonical nucleic acid structures involved in many biological processes. GQs formed in single-stranded regions often need to be unwound by cellular machinery, so their mechanochemical properties are important. Here, we performed steered molecular dynamics simulations of human telomeric GQs to study their unfolding. We examined four pulling regimes, including a very slow setup with pulling velocity and force load accessible to high-speed atomic force microscopy. We identified multiple factors affecting the unfolding mechanism, i.e.,: (i) the more the direction of force was perpendicular to the GQ channel axis (determined by GQ topology), the more the base unzipping mechanism happened, (ii) the more parallel the direction of force was, GQ opening and cross-

SUBMITTER: Stadlbauer P 

PROVIDER: S-EPMC10428220 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature