Qualitative SERS analysis of G-quadruplex DNAs using selective stabilising ligands

Area of Science:

• Biochemistry
• Molecular Biology
• Nanoscience

Background:

• Nucleic acids form diverse structures crucial for biological functions.
• Guanine-rich sequences form G-quadruplexes in genomic regions like telomeres and promoters.
• G-quadruplexes are significant in gene regulation and disease.

Purpose of the Study:

• To develop a novel method for detecting G-quadruplex formation.
• To utilize surface-enhanced Raman scattering (SERS) as a detection tool.
• To assess the dual role of G-quadruplex stabilizing ligands as therapeutic agents and SERS reporters.

Main Methods:

• Employed surface-enhanced Raman scattering (SERS) spectroscopy.
• Utilized three distinct G-quadruplex stabilizing ligands with unique SERS signatures.
• Developed an "on/off" detection strategy based on ligand SERS response.
• Tested the method with human telomeric and C-MYC promoter DNA sequences.

Main Results:

• A SERS response was observed only in the absence of G-quadruplex formation, enabling an "on/off" detection system.
• Successfully detected G-quadruplex formation qualitatively in human telomeric and C-MYC promoter DNA.
• Demonstrated that each ligand possesses a unique SERS spectrum, allowing for potential multiplexed detection.
• Confirmed the dual functionality of ligands as stabilizers and SERS reporters.

Conclusions:

• SERS provides a viable method for analyzing G-quadruplex DNA formation.
• The developed ligands can serve as both therapeutic agents and SERS-based analytical tools.
• This approach offers potential for studying higher-order DNA structures and their biological implications.