在大肠杆菌中SOS损伤向突变的一个模型
P Pham1, J G Bertram, M O'Donnell
1Department of Biological Sciences and Chemistry, University of Southern California, University Park, Los Angeles 90089-1340, USA.
Nature
|February 24, 2001
概括
这项研究模拟了DNA聚合酶Escherichia coli pol V如何准确地复制受损的DNA. 它解释了ReCA和SSB等蛋白质如何在DNA修复过程中防止未受损的部位发生错误.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 生物化学 生物化学
背景情况:
- 大肠杆菌pol V (UmuD'2C) 是一种参与转化合成的低保真性DNA聚合酶.
- 针对SOS损伤的向突变发生在SOS对DNA损伤反应期间诱导pol V时.
- 这一过程可能导致核酸的错误结合与模板病变相反.
研究的目的:
- 提出一种解释SOS损伤向突变发生的模型.
- 将特定的生物化学功能分配给参与转化合成的蛋白质.
- 阐明PolV针对受损DNA部位的机制.
主要方法:
- 生物化学测试研究蛋白质相互作用和功能.
- 在DNA合成过程中分析ReCA发光线动力学.
- 在ReCA和SSB的存在下,polV活动的表征.
主要成果:
- 聚合物V和SSB催化RECA光纤在3'到5'方向上的拆卸,在聚合酶之前.
- ATP水解驱动双向的ReCA导线从模板链剥离.
- 这种双向的崩限制了pol V的合成到损伤的近邻部位.
结论:
- 拟议的模型解释了pol V如何实现病变向突变发生.
- 聚V,Reca和SSB的协调作用可以最大限度地减少非目标突变.
- 这种机制确保了受损部位的有效和准确的DNA修复.
更多相关视频
11:36A Protocol for Functional Assessment of Whole-Protein Saturation Mutagenesis Libraries Utilizing High-Throughput Sequencing
Published on: July 3, 2016
10.3K
11:12Determination of the Optimal Chromosomal Locations for a DNA Element in Escherichia coli Using a Novel Transposon-mediated Approach
Published on: September 11, 2017
6.8K
相关概念视频
02:10Translesion DNA Polymerases
9.3K
Translesion (TLS) polymerases rescue stalled DNA polymerases at sites of damaged bases by replacing the replicative polymerase and installing a nucleotide across the damaged site. Doing so, TLS allows additional time for the cell to repair the damage before resuming regular DNA replication.
TLS polymerases are found in all three domains of life - archaea, bacteria, and eukaryotes. Of the different classes of TLS polymerases, members of the Y family are fitted with specialized structures that...
TLS polymerases are found in all three domains of life - archaea, bacteria, and eukaryotes. Of the different classes of TLS polymerases, members of the Y family are fitted with specialized structures that...
9.3K
01:20Mismatch Repair
5.4K
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...
5.4K