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Quantitative Detection of DNA-Protein Crosslinks and Their Post-Translational Modifications
Published on: April 21, 2023
Diepoxybutane interstrand cross-links induce DNA bending
Julie T Millard1, Erin E McGowan, Sharonda Q Bradley
1Department of Chemistry, Colby College, 5757 Mayflower Hill Drive, Waterville, ME 04901, USA. jtmillar@colby.edu
Biochimie
|August 16, 2011
Summary
The carcinogen 1,2,3,4-diepoxybutane (DEB) causes DNA damage by forming cross-links. This study reveals that DEB-induced DNA lesions cause significant DNA bending, impacting its structure.
Area of Science:
- Chemical carcinogenesis
- DNA damage and repair
- Molecular toxicology
Background:
- 1,2,3,4-diepoxybutane (DEB), a metabolite of 1,3-butadiene, is a suspected carcinogen.
- DEB induces DNA interstrand cross-links, primarily at 5'-GNC sequences.
- The formation of these cross-links necessitates DNA distortion due to the molecule's short tether.
Purpose of the Study:
- To investigate the structural consequences of DEB-induced DNA interstrand cross-links.
- To determine if DEB cross-links cause DNA bending.
Main Methods:
- Synthesis of ligated DNA oligomers containing DEB cross-links.
- Electrophoretic mobility assays to assess DNA structural changes.
- Analysis of mobility retardation to quantify DNA bending.
Main Results:
- DNA oligomers with DEB cross-links exhibited retarded electrophoretic mobility compared to controls.
- This retardation indicates a significant structural alteration in the DNA.
- Data suggest DNA bending of approximately 34° per lesion towards the major groove.
Conclusions:
- DEB-induced DNA interstrand cross-links induce significant DNA bending.
- This DNA bending may be a critical factor in the genotoxicity and carcinogenicity of DEB.
- Understanding DEB's structural impact on DNA is crucial for assessing 1,3-butadiene's carcinogenic risk.
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