Related Experiment Video
Updated: Aug 16, 2026
10:23
Time-Resolved Fluorescence Anisotropy from Single Molecules for Characterizing Local Flexibility in Biomolecules
Published on: April 25, 2025
Resolving the dynamics of atypical DNA structures using smFRET
Dorothy A Erie1, Sharonda J LeBlanc2, Keith R Weninger2
1Department of Chemistry and Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA.
Current Opinion in Structural Biology
|August 14, 2026
Summary
Single-molecule fluorescence resonance energy transfer (smFRET) reveals rapid DNA dynamics. This technique helps understand noncanonical DNA structures, protein interactions, and diseases like neurodegeneration.
Area of Science:
- Molecular Biology
- Biophysics
- Genomics
Background:
- B-form DNA is canonical, but noncanonical DNA structures (hairpins, G-quadruplexes, junctions) are crucial genomic drivers.
- These structures are dynamic and transient, posing challenges for traditional characterization methods.
- Understanding these structures is vital for insights into human diseases.
Purpose of the Study:
- To discuss the application of single-molecule fluorescence resonance energy transfer (smFRET) in studying DNA dynamics.
- To elucidate the role of noncanonical DNA structures in biological processes and disease.
- To highlight challenges in translating in vitro findings to in vivo systems.
Main Methods:
- Single-molecule fluorescence resonance energy transfer (smFRET) for sub-millisecond dynamics.
- Analysis of protein-induced DNA compaction mechanisms.
- Investigation of strand-slippage in tandem repeats linked to neurodegenerative diseases.
Main Results:
- smFRET enables characterization of rapid, transient DNA conformational changes.
- Insights into protein-DNA interactions and DNA compaction mechanisms.
- Understanding the molecular basis of strand-slippage in neurodegenerative diseases.
Conclusions:
- smFRET is essential for resolving dynamic noncanonical DNA structures.
- Studying DNA dynamics provides crucial insights into genomic functions and human diseases.
- Challenges remain in live-cell applications and potential label-induced perturbations.
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