Fluorescence Methods for Probing G-Quadruplex Structure in Single- and Double-Stranded DNA.

Area of Science:

• Molecular Biology
• Biochemistry
• Genetics

Background:

• G-quadruplex (G4) structures in nucleic acids are increasingly recognized for their biological significance and chemical properties.
• Traditional methods for G4 DNA analysis, such as dimethyl sulfate assays, polymerase stop assays, and nuclease digestion, often rely on radio-isotopic labels.
• Fluorescent labeling methods offer greater versatility and are becoming preferred over radio-isotopic techniques in many laboratories.

Purpose of the Study:

• To adapt traditional G4 DNA structural analysis procedures using fluorescent labels and capillary electrophoresis.
• To demonstrate the application of these novel fluorescent assays to well-characterized G4 structures, such as the c-MYC PU27 G4.
• To provide tools for interrogating G4 structures in both double- and single-stranded DNA substrates.

Main Methods:

• Adaptation of established G4 DNA structural analysis techniques.
• Implementation of fluorescent labeling instead of radio-isotopic labels.
• Utilization of capillary electrophoresis for high-resolution separation and detection.
• Application of chemical or enzymatic cleavage methods in conjunction with fluorescent assays.

Main Results:

• Successful adaptation of traditional G4 DNA probing methods using fluorescent labels and capillary electrophoresis.
• Demonstration of the utility of these assays on established G4 structures like c-MYC PU27 G4.
• Development of three distinct fluorescent assays capable of analyzing G4 structures in various DNA contexts.

Conclusions:

• The developed fluorescent assays provide a modern, non-radioactive alternative for G4 DNA structural analysis.
• These techniques are applicable to both double- and single-stranded DNA, offering broad utility.
• Combined application of these methods yields valuable insights into G4 topology, structure, and interactions with complementary strands.