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Related Experiment Video

Updated: Sep 2, 2025

Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes

Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes

Published on: April 4, 2025

Detecting G4 unwinding.

Stefan Juranek¹, Katrin Paeschke¹

¹Department of Oncology, Hematology and Rheumatology, University Hospital Bonn, Bonn, Germany.

Methods in Enzymology

|August 7, 2022

Summary

G-quadruplex structures (G4s) are stable DNA/RNA formations. This study details a protocol to monitor how helicase proteins unfold these G4 structures, preventing cellular defects.

Area of Science:

Molecular Biology
Genetics
Biochemistry

Background:

DNA can adopt various conformations beyond the standard B-DNA form.
G-quadruplex structures (G4s) are stable nucleic acid formations found in guanine-rich regions.
G4s form through Hoogsteen hydrogen bonding, creating stacked G quartets.

Purpose of the Study:

To provide a detailed protocol for monitoring G-quadruplex structure unfolding by helicases.
To investigate the cellular mechanisms regulating G4 formation and resolution.

Main Methods:

The study describes a specific protocol to observe the unfolding of G4 structures.
This protocol focuses on the activity of helicase proteins in resolving G4s.
Methods involve monitoring G4 structure dynamics and helicase-mediated disruption.

Keywords:

G-quadruplex structures G-quadruplexes Guanine tetrads Helicases

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Main Results:

Accumulating data supports the in vivo formation and biological relevance of G4 structures.
Cellular processes tightly regulate G4 formation and unfolding.
Persistent G4s can lead to cellular defects like genome instability.

Conclusions:

Helicases are crucial proteins that cells utilize to unfold G4 DNA and RNA structures.
Preventing G4 accumulation is essential for maintaining cellular integrity.
The described protocol aids in understanding G4 unfolding mechanisms.