Benzothiazole-substituted benzofuroquinolinium dye: a selective switch-on fluorescent probe for G-quadruplex

Area of Science:

• Chemical Biology
• Molecular Biology
• Biophysical Chemistry

Background:

• G-quadruplexes are four-stranded DNA structures with significant biological roles.
• Developing selective probes for G-quadruplexes is crucial for understanding their function and for therapeutic development.

Purpose of the Study:

• To design and synthesize a novel fluorescent probe with high selectivity for G-quadruplex nucleic acid structures.
• To investigate the binding mechanism and fluorescence response of the probe to G-quadruplexes.

Main Methods:

• Synthesis of a fluorescent probe incorporating a benzofuroquinolinium (binding scaffold) and benzothiazole (signalling unit).
• Fluorescence spectroscopy to assess probe response and selectivity.
• Binding studies to elucidate the interaction mode with G-quadruplex DNA.

Main Results:

• The synthesized probe demonstrated a switch-on fluorescence response.
• The probe exhibited remarkable selectivity for G-quadruplex structures over other nucleic acid forms.
• Binding studies confirmed end-stack binding as the mechanism for selective G-quadruplex recognition.

Conclusions:

• The novel fluorescent probe is highly selective for G-quadruplex DNA.
• The probe's selectivity is attributed to end-stack binding interactions.
• This probe represents a valuable tool for studying G-quadruplex structures in biological systems.