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Updated: May 31, 2026

Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes
Published on: April 4, 2025
A stabilizing and denaturing dual-effect for natural polyamines interacting with G-quadruplexes depending on
Hongxia Sun1, Junfeng Xiang, Yan Liu
1National Laboratory for Molecular Sciences, Center for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing, PR China.
Natural polyamines show a dual effect on G-quadruplexes, stabilizing them at low concentrations but denaturing them at high concentrations. This impacts tumor growth and proliferation research.
Area of Science:
- Biochemistry and Molecular Biology
- Cancer Research
- Structural Biology
Background:
- G-quadruplexes are nucleic acid structures implicated in cancer.
- Natural polyamines are linked to tumor growth and proliferation.
- Understanding their interaction is crucial for cancer therapeutics.
Purpose of the Study:
- To investigate the concentration-dependent effect of natural polyamines on telomeric and oncogenic G-quadruplexes.
- To elucidate the mechanisms behind polyamine-induced stabilization and denaturation of G-quadruplexes.
Main Methods:
- Absorption spectroscopy
- Fluorescence spectroscopy
- Circular Dichroism (CD)
- Nuclear Magnetic Resonance (NMR)
Main Results:
- Natural polyamines exhibit a dual effect on G-quadruplex stability.
- Lower polyamine concentrations (<1mM) promote and stabilize G-quadruplexes.
- Higher polyamine concentrations (>1mM) lead to G-quadruplex denaturation.
Conclusions:
- Polyamines can stabilize G-quadruplexes through electrostatic and hydrophobic interactions.
- Denaturation at higher concentrations may involve hydrogen-bonding disruption.
- The concentration-dependent effects of polyamines on G-quadruplexes have significant implications for cancer biology.
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