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Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes
Published on: April 4, 2025
G-quadruplexes incorporating modified constituents: a review
1a Rimstone Laboratory , RLI, 29 Lancaster Way, Cheshire , CT , 06410 , USA .
Journal of Biomolecular Structure & Dynamics
|March 27, 2013
Summary
This review explores modified guanine analogs in DNA and RNA G-quadruplexes. These analogs enhance structural stability, aiding detailed analysis of these important nucleic acid structures.
Area of Science:
- Biochemistry
- Structural Biology
- Nucleic Acid Chemistry
Background:
- G-quadruplexes are four-stranded nucleic acid structures with significant biological roles.
- Understanding G-quadruplex structure is crucial for therapeutic development.
- Natural nucleotide building blocks can be modified to probe these structures.
Purpose of the Study:
- To review structural studies of G-quadruplexes using modified nucleotides.
- To identify useful guanine analogs for G-quadruplex structural characterization.
- To assess the impact of modifications on G-quadruplex stability and topology.
Main Methods:
- Incorporation of base, sugar, and phosphate derivatives into DNA and RNA oligonucleotides.
- Synthesis and characterization of over 50 modified G-quadruplex forming sequences.
- Stability and folding topology analysis using biophysical techniques.
Main Results:
- Several guanine analogs, including 2-aminopurine, 8-bromoguanine, 8-methylguanine, and hypoxanthine, were evaluated.
- These analogs were incorporated into various G-quadruplex forming sequences like TG4T, TG5T, thrombin aptamer, and human telomere repeat.
- 8-bromoguanine, 8-methylguanine, and hypoxanthine stabilize specific G-quadruplex folds, facilitating structural determination.
Conclusions:
- Modified nucleotides, particularly specific guanine analogs, are valuable tools for G-quadruplex structural studies.
- These analogs improve the accuracy and feasibility of structural determination using techniques like CD and NMR.
- The findings support the use of modified nucleic acids in understanding complex biological structures.
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