相关实验视频
Updated: Jun 15, 2026

10:59
Visualizing and Quantifying Endonuclease-Based Site-Specific DNA Damage
Published on: August 21, 2021
替代核酸切割修复途径用于氧化DNA损伤的替代核酸切割修复途径
Alexander A Ischenko1, Murat K Saparbaev
1Groupe "Réparation de l'ADN", UMR 8532 CNRS, LBPA-ENS Cachan, Institut Gustave Roussy, 94805 Villejuif Cedex, France.
Nature
|January 24, 2002
概括
另一种替代的DNA修复途径绕过了DNA糖酶系统,该系统与氧化损伤作斗争. 类似Nfo的内核酶通过在氧化基附近断DNA来启动修复,从而为随后的合成创造了合适的末端.
科学领域:
- 分子生物学分子生物学
- DNA 修复机制的修复机制
- 氧化应激反应的反应
背景情况:
- 氧化DNA损伤修复的标准DNA糖酶途径由于中间处理步骤,是低效的.
- 生物证据表明存在另一种途径,因为某些缺乏DNA糖系酶的突变体对活性氧物种有抗性.
研究的目的:
- 研究Nfo类内核酶在替代氧化DNA损伤修复途径中的作用.
- 描述Nfo类内核酶在各种氧化基上的DNA切割活性.
主要方法:
- 酶性测试以评估Nfo类内核酶的DNA断活性.
- 由Nfo类内核酶产生的DNA末端的表征.
- 测试生成的终端对于下游修复合成酶的适用性.
主要成果:
- 类似Nfo的内核酶将DNA 5'接到几种氧化损伤的基,包括5,6-二二胺和5-基 uracil.
- 这种切割产生3'-基和5'-酸盐末端,非常适合DNA修复合成.
- 随后,受损的核酸被结构内核酶和DNA聚合酶I所去除.
结论:
- 类似nfo的内核酶是另一种更有效的氧化DNA损伤修复途径的关键组成部分.
- 这种途径通过直接生成适合DNA修复合成的基质来克服DNA糖酶系统的局限性.
相关概念视频
Base Excision Repair
One of the common DNA damages is the chemical alteration of single bases by alkylation, oxidation, or deamination. The altered bases cause mispairing and strand breakage during replication. This type of damage causes minimal change to the DNA double helix structure and can be repaired by the base excision repair (BER) pathways. BER corrects damaged DNA sequences by removing the damaged base and restoring the original base sequence using the complementary strand as a template.
The first step of...
The first step of...
Base Excision Repair
One of the common DNA damages is the chemical alteration of single bases by alkylation, oxidation, or deamination. The altered bases cause mispairing and strand breakage during replication. This type of damage causes minimal change to the DNA double helix structure and can be repaired by the base excision repair (BER) pathways. BER corrects damaged DNA sequences by removing the damaged base and restoring the original base sequence using the complementary strand as a template.
The first step of...
The first step of...
Nucleotide Excision Repair
Overview
Nucleotide Excision Repair
DNA Distortion and Damage
Cells are regularly exposed to mutagens—factors in the environment that can damage DNA and generate mutations. UV radiation is one of the most common mutagens and is estimated to introduce a significant number of changes in DNA. These include bends or kinks in the structure, which can block DNA replication or transcription. If these errors are not fixed, the damage can cause mutations, which in turn can result in cancer or disease depending on which sequences are...
Cells are regularly exposed to mutagens—factors in the environment that can damage DNA and generate mutations. UV radiation is one of the most common mutagens and is estimated to introduce a significant number of changes in DNA. These include bends or kinks in the structure, which can block DNA replication or transcription. If these errors are not fixed, the damage can cause mutations, which in turn can result in cancer or disease depending on which sequences are...
Nucleotide Excision Repair
Overview
Overview of DNA Repair
In order to be passed through generations, genomic DNA must be undamaged and error-free. However, every day, DNA in a cell undergoes several thousand to a million damaging events by natural causes and external factors. Ionizing radiation such as UV rays, free radicals produced during cellular respiration, and hydrolytic damage from metabolic reactions can alter the structure of DNA. Damages caused include single-base alteration, base dimerization, chain breaks, and cross-linkage.
Chemically...
Chemically...

