在人类无细胞系统中,依赖循环素/Cdk启动DNA复制
1Wellcome Trust/Cancer Research Campaign Institute, University of Cambridge, United Kingdom.
Cell
|January 10, 1997
概括
使用无细胞系统研究了DNA复制启动的细胞周期控制. 对于启动G1阶段核中的DNA复制来说,S阶段细胞溶液提取物和特定的循环素依赖激酶 (CDK) 如循环素A/Cdk2和循环素E/Cdk2至关重要.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- DNA复制是一个由细胞周期严格调节的基本过程.
- 了解启动DNA复制的分子机制对于细胞周期控制研究至关重要.
研究的目的:
- 为了研究DNA复制启动的无细胞系统.
- 为了确定S相细胞质和特定的循环素依赖激酶 (CDK) 中的关键因素,这些激酶调节DNA复制启动.
主要方法:
- 利用来自HeLa细胞的无细胞系统.
- 同时化G1和G2相核与S相核和细胞质提取物.
- 评估了重组人体循环素 (A,E,B1) 和CDKs (Cdk2,Cdc2) 在DNA复制中的作用.
主要成果:
- 在G1核中,当与S相细胞质和S相核化时,发生了DNA复制启动.
- 启动需要S相核提取物或特定的环素-CDK复合物 (环素A/Cdk2,环素E/Cdk2),而不是延长.
- 环素A/Cdk2和E/Cdk2协同触发了S相细胞质中的启动.
结论:
- 无细胞系统有效地复制了细胞周期控制的DNA复制启动.
- 环素A/Cdk2和环素E/Cdk2复合体是G1阶段启动DNA复制的关键调节剂.
- 这些发现提供了对控制细胞循环依赖DNA复制的分子机制的见解.
相关概念视频
01:45Positive Regulator Molecules
To consistently produce healthy cells, the cell cycle—the process that generates daughter cells—must be precisely regulated.
02:39Positive Regulator Molecules
Mitotic cell division results in daughter cells that exactly resemble the parent cell. However, errors in the DNA replication or distribution of genetic material may lead to genetic mutations that may be passed down to every new cell formed from the resulting abnormal cell. Propagation of such mutant cells is restricted through checkpoint mechanisms present at different stages of the cell cycle. These checkpoints involve regulator molecules that either promote or demote cell cycle events.
02:34Inhibition of Cdk Activity
The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...
02:38S-Cdk Initiates DNA Replication
The cell cycle is a series of events leading to DNA duplication followed by the division of cell content to form two daughter cells. The cell cycle progresses in four stages—the cell increases in size (gap 1 or G1-phase), duplicates its DNA (synthesis or S-phase), prepares to divide (gap 2 or G2-phase), and divides (mitosis or M-phase).
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.
02:34Inhibition of CDK Activity
The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...
02:38S-Cdk Initiates DNA Replication
The cell cycle is a series of events leading to DNA duplication followed by the division of cell content to form two daughter cells. The cell cycle progresses in four stages—the cell increases in size (gap 1 or G1-phase), duplicates its DNA (synthesis or S-phase), prepares to divide (gap 2 or G2-phase), and divides (mitosis or M-phase).
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.
Two states at the origin of replication
In eukaryotes, the initiation of replication occurs at many sites on the chromosomes, called the origins of replication.