不匹配修复蛋白MutS的晶体结构及其与基质DNA复合物的复合物
1Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
Nature
|October 26, 2000
概括
修复DNA不匹配的蛋白质MutS对于DNA复制的真实性至关重要. 晶体结构揭示了MutS如何识别DNA不匹配及其在遗传性非多重性结直肠癌中的作用.
科学领域:
- 分子生物学分子生物学
- 结构生物学 结构生物学
- 遗传学 遗传学 是一个
背景情况:
- 通过纠正DNA复制过程中的错误,DNA不匹配修复 (MMR) 对于保持基因组稳定性至关重要.
- MutS蛋白是MMR途径的关键组成部分,负责识别DNA不匹配.
- 人类MutS基因的缺陷与遗传性非多重性结直肠癌 (HNPCC) 和其他癌症有关.
研究的目的:
- 阐明 MutS 蛋白质对DNA不匹配识别的结构基础.
- 了解MutS在启动DNA不匹配修复中的机制.
- 为了解MutS.中的癌症相关突变提供一个分子框架.
主要方法:
- 采用X射线结晶学来确定一个MutS蛋白的结构.
- 确定了一种MutS-DNA复合体的晶体结构,该复合体含有带有未配对基的异质复合体.
- 结构分析的重点是MutS-DNA相互作用,域架构和活跃站点组成.
主要成果:
- 晶体结构揭示了 MutS 蛋白质的整体结构.
- 确定了一种诱导适合机制,用于识别不匹配,涉及四个MutS二元域和一个扭曲的DNA异质复合体.
- 由MutS子单元和发射器区域的残留物形成的复合ATPase活性位点的特征.
结论:
- 确定的结构为DNA不匹配识别和修复的分子机制提供了前所未有的洞察力.
- 这些结构信息为理解HNPCC和其他与癌症相关的MutS突变提供了分子基础.
- 这些发现为未来对MutS功能研究和向癌症治疗的开发铺平了道路.
相关概念视频
01:36Mismatch Repair
Overview
01:08Nucleotide Excision Repair
Overview
01:36Mismatch Repair
Overview
01:08Nucleotide Excision Repair
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01:38Nucleotide 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...
01:20Mismatch Repair
Organisms are capable of detecting and fixing nucleotide mismatches that occur during DNA replication. This sophisticated process requires identifying the new strand and replacing the erroneous bases with correct nucleotides. Mismatch repair is coordinated by many proteins in both prokaryotes and eukaryotes.
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...
The Mutator Protein Family Plays a Key Role in DNA Mismatch Repair
The human genome has more than 3 billion base pairs of DNA per cell. Prior to cell division, that vast amount of genetic...