Related Experiment Video
Updated: Sep 21, 2025
09:32
Stable DNA Motifs, 1D and 2D Nanostructures Constructed from Small Circular DNA Molecules
Published on: April 12, 2019
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Spontaneous DNA Synapsis by Forming Noncanonical Intermolecular Structures
Viacheslav Severov1, Vladimir Tsvetkov1,2,3, Nikolay Barinov1
1Federal Research and Clinical Center of Physical-Chemical Medicine, Malaya Pirogovskaya Str. 1a, 119435 Moscow, Russia.
Polymers
|May 28, 2022
Summary
We discovered spontaneous DNA-DNA junctions, potentially forming G-quadruplex structures, without proteins. These novel DNA conjugates may influence chromatin and genomic rearrangements.
Area of Science:
- Molecular Biology
- Biophysics
- Genomics
Background:
- DNA structures can form noncanonical conformations.
- Protein-mediated DNA interactions are well-studied.
- The role of spontaneous DNA structures in genome organization is less understood.
Purpose of the Study:
- To investigate the spontaneous formation of DNA-DNA junctions in solution.
- To characterize the structural and binding properties of these junctions.
- To explore the potential implications of these structures in chromatin architecture.
Main Methods:
- Atomic force microscopy (AFM) for visualization.
- G-quadruplex (G4) antibody assays for binding studies.
- Molecular modeling for structural elucidation.
Main Results:
- Spontaneous formation of DNA-DNA junctions observed via AFM.
- Junctions located at potential G-quadruplex (G4) sites.
- Conjugates showed affinity for G4 antibodies, unlike Holliday junctions.
- Molecular modeling suggested possible G4/IM-synaptic complex structures.
Conclusions:
- Intermolecular noncanonical DNA structures can form spontaneously.
- These structures may play a role in chromatin organization.
- Potential involvement in genomic rearrangement processes.
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