Related Experiment Video
Updated: Jun 3, 2025
05:37
Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes
Published on: April 4, 2025
341
Higher-Order DNA Secondary Structures and Their Transformations: The Hidden Complexities of Tetrad and Quadruplex DNA
Jens Völker1, Vera Gindikin1, Kenneth J Breslauer1,2
1Department of Chemistry and Chemical Biology, Rutgers University, 123 Bevier Rd, Piscataway, NJ 08854, USA.
Biomolecules
|January 8, 2025
Summary
Short DNA sequences can disrupt G-quadruplex structures, altering DNA conformations. This strand invasion mechanism offers potential for controlling DNA states and biomedical applications.
Area of Science:
- Molecular Biology
- Biophysics
- Structural Biology
Background:
- G-quadruplexes are noncanonical DNA secondary structures with significant biological roles.
- Understanding DNA conformational dynamics is crucial for molecular biology and medicine.
Purpose of the Study:
- To investigate the effects of oligonucleotide strand invasion on G-quadruplex DNA structures.
- To explore the potential of manipulating DNA conformations for biomedical applications.
Main Methods:
- Spectroscopic mapping of DNA reactants and products.
- Analysis of DNA secondary structure disruption and formation.
- Investigation of kinetic processes and metastability in DNA folding.
Main Results:
- Strand invasion disrupts G-quadruplex and invading strand structures, forming iDNA tetrads.
- Kinetic processes and sample history significantly influence DNA state populations.
- Topological constraints impact the stability of base-paired DNA domains.
Conclusions:
- Oligonucleotide invasion offers a pathway to control and unfold kinetically trapped DNA states.
- Designed invading oligonucleotides can manipulate noncanonical DNA conformations for biomedical use.
- Strand invasion induces coupled transformations between DNA forms, relevant to biological regulation.
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