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Updated: Jun 10, 2026
05:37
Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes
Published on: April 4, 2025
Cation involvement in telomestatin binding to g-quadruplex DNA.
Frédéric Rosu1, Valérie Gabelica, Nicolas Smargiasso
1Mass Spectrometry Laboratory, Department of Chemistry, University of Liège, 4000 Liège, Belgium.
Journal of Nucleic Acids
|August 12, 2010
Summary
Telomestatin binds to G-quadruplex DNA by coordinating cations, similar to a crown ether. This cation coordination is crucial for designing effective G-quadruplex binding ligands.
Area of Science:
- Molecular Biology
- Medicinal Chemistry
- Biophysical Chemistry
Background:
- G-quadruplex DNA structures are targets for therapeutic intervention.
- Telomestatin is a known ligand that interacts with G-quadruplex DNA.
Purpose of the Study:
- To elucidate the binding mode of telomestatin to G-quadruplex DNA.
- To understand the role of cations in telomestatin-G-quadruplex interactions.
Main Methods:
- Electrospray mass spectrometry was used to detect intact telomestatin-G-quadruplex complexes.
- Density functional theory calculations were performed to model the complex.
Main Results:
- Mass spectrometry revealed the incorporation of an ammonium ion into telomestatin complexes.
- Telomestatin demonstrated cation coordination capabilities akin to crown ethers.
- Computational studies indicated cations are situated between telomestatin and G-quartets in the complex.
Conclusions:
- Monovalent cation coordination is a key feature of telomestatin binding to G-quadruplex DNA.
- This cation binding property should be considered in the design of novel G-quadruplex ligands.
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