通过准对称的螺旋酶负载建立双向真核DNA复制
Gideon Coster1, John F X Diffley2
1Francis Crick Institute, London NW1 1AT, UK.
概括
有效的DNA复制需要两个起源识别复合体 (ORC) 蛋白来结合DNA,它们的方向,而不是距离,对于加载两个微染色体维护 (MCM) 螺旋酶进行双向复制至关重要.
科学领域:
- 分子生物学
- 遗传学
- 生物化学
背景情况:
- 在真核生物中,双向DNA复制需要将两个环形的微染色体维护 (MCM) 螺旋酶在相反的方向上加载到DNA上.
- 原始识别复合体 (ORC) 绑定DNA启动MCM加载,但协调对称MCM加载的机制尚不清楚.
研究的目的:
- 阐明原始识别复合体 (ORC) 如何在真核生物DNA复制原点协调两个微染色体维护 (MCM) 螺旋酶的对称负载.
- 调查ORC结合点号,距离和方向在MCM加载和原始函数中的作用.
主要方法:
- 使用了天然发芽酵母DNA复制来源和合成DNA序列.
- 进行了体外测试,以评估MCM的负载效率.
- 在体内评估原产地功能.
主要成果:
- 有效的MCM加载需要两个ORC分子与两个不同的ORC结合点结合.
- ORC结合点的相对方向对于MCM加载和起源功能至关重要,而它们之间的距离则不至关重要.
- 证明了ORC结合部位在体外MCM负载和体内起源功能的重要性.
结论:
- 提出一种在古生物和真核生物中双向复制的统一机制,其中包括ORC的准对称MCM六合体加载.
- 建议指向的MCM转移到双重六合体是建立双向复制的关键.
- 强调ORC结合点在调节DNA复制启动中的关键作用.
相关概念视频
Replication in Eukaryotes
18.0K
In eukaryotic cells, DNA replication is highly conserved and tightly regulated. Multiple linear chromosomes must be duplicated with high fidelity before cell division, so there are many proteins that fulfill specialized roles in the replication process. Replication occurs in three phases: initiation, elongation, and termination, and ends with two complete sets of chromosomes in the nucleus.
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...
18.0K
Replication in Eukaryotes
206.2K
Overview
206.2K
Replication in Prokaryotes
28.4K
DNA replication has three main steps: initiation, elongation, and termination. Replication in prokaryotes begins when initiator proteins bind to the single origin of replication (ori) on the cell's circular chromosome. Replication then proceeds around the entire circle of the chromosome in each direction from the two replication forks, resulting in two DNA molecules.
Many Proteins Work Together to Replicate the Chromosome
Replication is coordinated and carried out by a host of specialized...
Many Proteins Work Together to Replicate the Chromosome
Replication is coordinated and carried out by a host of specialized...
28.4K
Replication in Prokaryotes
99.9K
Overview
99.9K
Homologous Recombination
64.3K
The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...
64.3K
Homologous Recombination
7.0K
7.0K


