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Updated: Jun 20, 2025
08:28
Single-molecule Manipulation of G-quadruplexes by Magnetic Tweezers
Published on: September 19, 2017
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Strategy for modeling higher-order G-quadruplex structures recalcitrant to NMR determination
T Michael Sabo1, John O Trent1, Jonathan B Chaires1
1UofL Health Brown Cancer Center, University of Louisville, Louisville, KY, United States.
Methods (San Diego, Calif.)
|July 20, 2024
Summary
Researchers developed an integrated structural biology platform to characterize complex G-quadruplexes (G4s) and higher-order G4s (xG4s). This method enables modeling of biologically relevant xG4 structures for potential therapeutic targeting.
Area of Science:
- Structural Biology
- Biochemistry
- Genetics
Background:
- Guanine-rich nucleic acids form G-quadruplexes (G4s), with research traditionally focusing on simple, short sequences.
- Longer sequences with multiple G4 repeats, found in proto-oncogene promoters and telomeres, suggest complex higher-order structures (xG4s).
- These xG4s may offer selective drug-targeting sites for therapeutic development but are challenging to characterize.
Purpose of the Study:
- To develop and present an integrated structural biology (ISB) platform for characterizing complex higher-order G-quadruplexes (xG4s).
- To demonstrate the utility and generality of the ISB approach for biologically relevant xG4s.
Main Methods:
- Development of an integrated structural biology (ISB) platform.
- Combination of experimental and computational methods.
- Application of the ISB platform to model extended c-Myc promoter and long human telomere G4 repeats.
Main Results:
- Successful application of the ISB platform to characterize complex xG4 structures.
- Generation of self-consistent molecular models for biologically relevant xG4s.
- Demonstration of the ISB platform's utility and generality.
Conclusions:
- The ISB platform provides a robust method for structural characterization of complex xG4s.
- This approach facilitates the study of biologically relevant xG4s, aiding in the identification of potential therapeutic targets.
- The ISB platform overcomes limitations of traditional high-resolution methods for complex G4 structures.
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