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Updated: Aug 9, 2026

Using Next Generation Sequencing to Identify Mutations Associated with Repair of a CAS9-induced Double Strand Break Near the CD4 Promoter
Published on: March 31, 2022
DNA strand breaks induced by near-zero-electronvolt electron attachment to pyrimidine nucleotides
Xiaoguang Bao1, Jing Wang, Jiande Gu
1Drug Design and Discovery Center, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 201203, People's Republic of China.
Low-energy electrons (LEE) can induce DNA strand breaks by attaching to pyrimidine bases, forming radical anions. This process primarily involves C-O bond breaking, leading to DNA damage.
Area of Science:
- Computational chemistry
- Molecular biology
- Radiation chemistry
Background:
- Low-energy electrons (LEE) are implicated in DNA damage.
- Understanding the precise mechanisms of LEE-induced DNA strand breaks is crucial.
Purpose of the Study:
- To elucidate the mechanism of DNA strand breaks induced by low-energy electrons.
- To investigate the C(5')-O(5') sigma bond breaking in pyrimidine nucleotides.
Main Methods:
- Theoretical investigations using the B3LYP/DZP++ approach.
- Simulations performed in both gas phase and aqueous solution.
Main Results:
- Pyrimidine nucleotides capture near-0-eV electrons, forming stable radical anions.
- LEE-induced DNA strand breaks involve electron attachment to bases, forming base-centered radical anions.
- C-O bond cleavage is the dominant pathway due to low activation energy.
Conclusions:
- The study provides a detailed mechanism for LEE-induced DNA strand breaks.
- C-O bond breaking is a key step in this damage pathway.
- Electron affinities increase in aqueous solutions, stabilizing radical anions.
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