A Catalytic and Selective Scissoring Molecular Tool for Quadruplex Nucleic Acids

Area of Science:

• Supramolecular Chemistry
• DNA Nanotechnology
• Chemical Biology

Background:

• G-quadruplex DNA structures play roles in various biological processes.
• Targeting G-quadruplexes is a strategy for therapeutic intervention.
• Developing selective G-quadruplex binders and cleavers is crucial.

Purpose of the Study:

• To design and characterize a copper complex for G-quadruplex DNA binding and cleavage.
• To investigate the catalytic activity of the complex in reactive oxygen species (ROS) generation.
• To elucidate the selectivity mechanism for G-quadruplex cleavage.

Main Methods:

• Synthesis and characterization of a copper complex integrated into a naphthalene diimide scaffold.
• Förster Resonance Energy Transfer (FRET) melting assays.
• Circular Dichroism (CD) spectroscopy.
• Nuclear Magnetic Resonance (NMR) spectroscopy.
• Gel electrophoresis for DNA sequencing.
• Mass spectrometry.

Main Results:

• The designed copper complex effectively binds and cleaves G-quadruplex DNA.
• The complex exhibits catalytic activity in generating ROS.
• Experiments revealed unexpected selectivity in cleaving specific G-quadruplex sequences.
• Selectivity was attributed to both binding affinity and the structural characteristics of the target G-quadruplexes.

Conclusions:

• A novel copper complex demonstrates potent and selective G-quadruplex DNA cleavage.
• The complex's activity is linked to ROS generation and specific G-quadruplex structural recognition.
• This work provides a foundation for developing targeted G-quadruplex-based therapeutics.