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Updated: Jul 22, 2026
16:24
Analyzing and Building Nucleic Acid Structures with 3DNA
Published on: April 26, 2013
High-resolution structure of a DNA helix forming (C.G)*G base triplets
L Van Meervelt1, D Vlieghe, A Dautant
1Department of Chemistry, Katholieke Universiteit Leuven, Heverlee, Belgium.
Nature
|April 20, 1995
Summary
High-resolution X-ray crystallography reveals DNA triple helix structures. This provides insights into gene regulation and homologous recombination mechanisms.
Area of Science:
- Structural Biology
- Molecular Biology
- Biochemistry
Background:
- Triple helices form from interactions between single- and double-stranded nucleic acids.
- Their formation is implicated in homologous recombination and gene activity control.
- Limited high-resolution structural data exists for triple helix motifs.
Purpose of the Study:
- To determine the high-resolution structure of a DNA nonamer forming a triple helix.
- To provide structural insights into sequence-specific nucleic acid interactions.
Main Methods:
- X-ray diffraction analysis.
- Crystallography.
- Structural determination of DNA nonamer d(GCGAATTCG) to 2.05 A resolution.
Main Results:
- The crystal structure revealed (C.G)*G triplets forming a DNA triple helix fragment.
- The guanosine-containing chains adopted a parallel orientation.
- The structure aligns with predictions for triplex organization.
Conclusions:
- The study provides the first high-resolution X-ray structure of a DNA triple helix.
- This structure offers an accurate model for sequence-specific association between nucleic acid strands.
- The findings support models of homologous recombination involving parallel triplex formation.
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