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In Vitro Chemical Mapping of G-Quadruplex DNA Structures by Bis-3-Chloropiperidines
Published on: May 12, 2023
G-quadruplex structure and stability illuminated by 2-aminopurine phasor plots
Robert Buscaglia1, David M Jameson, Jonathan B Chaires
1James Graham Brown Cancer Center, University of Louisville, 505 S. Hancock Street, Louisville, KY 40202, USA.
Nucleic Acids Research
|January 14, 2012
Summary
Phasor diagrams simplify complex fluorescence data, enabling easier study of telomeric G-quadruplex folding and stability. This method offers a powerful tool for analyzing intricate nucleic acid structures.
Area of Science:
- Biophysics
- Molecular Biology
- Analytical Chemistry
Background:
- Time-resolved fluorescence measurements are crucial for studying telomeric G-quadruplex folding and stability.
- Complex fluorescence lifetime distributions in solution have hindered these analyses.
- Phasor diagrams offer a novel approach to simplify and analyze these complex datasets.
Purpose of the Study:
- To demonstrate the utility of phasor diagrams for analyzing complex time-resolved fluorescence data from telomeric G-quadruplexes.
- To showcase the application of phasor diagrams in monitoring G-quadruplex folding, stability, and structural changes.
- To present phasor diagrams as a model-free graphical method for characterizing complex fluorescence lifetime distributions.
Main Methods:
- Utilized time-resolved fluorescence measurements (frequency-domain and time-domain).
- Applied phasor diagram analysis to transformed time-resolved fluorescence results.
- Investigated a 2-aminopurine substituted telomeric G-quadruplex sequence.
- Compared phasor diagram analysis with traditional non-linear regression model fitting.
Main Results:
- Phasor diagrams effectively simplified complex fluorescent decays.
- The folding and stability of telomeric G-quadruplexes were monitored in the presence of sodium and potassium ions.
- Multiple transitions during telomeric G-quadruplex folding induced by potassium were identified.
- Phasor diagrams successfully monitored enzymatic digestion, fluorescence quenching, and Förster resonance energy transfer.
Conclusions:
- Phasor diagrams provide a rapid and model-free method for characterizing complex fluorescence lifetime distributions.
- This approach enhances the sensitivity of time-resolved methods for monitoring changes in telomeric G-quadruplex structures.
- The phasor diagram method is applicable to various G-quadruplex and nucleic acid systems.
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