Visualization of G-quadruplexes by using a BODIPY-labeled macrocyclic heptaoxazole

Area of Science:

• Biochemistry
• Molecular Biology
• Chemical Biology

Background:

• G-quadruplexes are non-canonical DNA structures implicated in various cellular processes.
• Developing selective ligands for G-quadruplexes is crucial for understanding their biological roles and for therapeutic applications.
• Fluorescent probes offer a powerful tool for real-time detection and imaging of nucleic acid structures.

Purpose of the Study:

• To develop a novel fluorescent ligand for the detection and stabilization of G-quadruplexes.
• To investigate the ability of the ligand to selectively induce and bind to intramolecular G-quadruplexes.
• To demonstrate the utility of the ligand for visualizing G-quadruplexes in a cellular context.

Main Methods:

• Synthesis and characterization of a BODIPY-labeled macrocyclic heptaoxazole (L1BOD-7OTD).
• Spectroscopic studies to assess ligand binding and stabilization of G-quadruplex forming oligonucleotides (GFOs).
• Fluorescence microscopy to visualize G-quadruplex formation in vitro and in cells.

Main Results:

• L1BOD-7OTD selectively induces intramolecular G-quadruplex formation in specific GFOs.
• The ligand exhibits strong binding affinity and stabilizing effects on intramolecular G-quadruplexes.
• Direct visualization of G-quadruplexes was achieved through green fluorescence emission of L1BOD-7OTD.
• The study provided evidence for the formation of G-quadruplexes within living cells using the developed probe.

Conclusions:

• L1BOD-7OTD is an effective fluorescent ligand for G-quadruplexes, capable of inducing, stabilizing, and visualizing these structures.
• The findings validate the use of L1BOD-7OTD for studying G-quadruplexes in biological systems.
• This fluorescent probe opens new avenues for investigating the cellular roles of G-quadruplexes.