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Updated: Feb 3, 2026

Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes
Published on: April 4, 2025
Binding Modes and Selectivity of Ruthenium Complexes to Human Telomeric DNA G-Quadruplexes
Jenifer Rubio-Magnieto1,2, Sofia Kajouj3, Florent Di Meo4
1Laboratory for Chemistry of Novel Materials, Center for Innovation in Materials and Polymers, University of Mons-UMONS, 20 Place du Parc, 7000, Mons, Belgium.
Abstract:
Metal complexes constitute an important class of DNA binders. In particular, a few ruthenium polyazaaromatic complexes are attractive as "light switches" because of their strong luminescence enhancement upon DNA binding. In this paper, a comprehensive study on the binding modes of several mononuclear and binuclear ruthenium complexes to human telomeric sequences, made of repeats of the d(TTAGGG) fragment is reported. These DNA sequences form G-quadruplexes (G4s) at the ends of chromosomes and constitute a relevant biomolecular target in cancer research. By combining spectroscopy experiments and molecular modelling simulations, several key properties are deciphered: the binding modes, the stabilization of G4 upon binding, and the selectivity of these complexes towards G4 versus double-stranded DNA. These results are rationalized by assessing the possible deformation of G4 and the binding free energies of several binding modes via modelling approaches. Altogether, this comparative study provides fundamental insights into the molecular recognition properties and selectivity of Ru complexes towards this important class of DNA G4s.
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