在人类细胞周期的G1阶段形成和激活一个环林E-cdk2复合体
1Department of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98104.
Science (New York, N.Y.)
|September 18, 1992
概括
人类环林E蛋白与环林依赖激酶2 (Cdk2) 合作,在G1阶段调节细胞分裂. 这种环林-Cdk2复合体对于真核细胞的细胞增殖至关重要.
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:
- 人类环林E最初被鉴定为其作为酵母中的G1环林的作用.
- 细胞循环调节是真核生物体的一个基本过程.
研究的目的:
- 研究人类环林E在细胞循环调节中的作用.
- 为了识别与人类环林E相关的激酶及其在细胞周期中的活性.
主要方法:
- 生物化学分析检测酶活性.
- 免疫注射以评估蛋白质的丰富性.
- 细胞周期同步和分析.
主要成果:
- 循环E与人类细胞中细胞循环调节的蛋白激酶相关.
- 与环林E相关的酶活性峰值发生在G1阶段.
- 主要的环素E相关激酶被确定为Cdk2 (环素依赖激酶2).
- 环素E和环素E-Cdk2复合物的丰度在G1阶段细胞中最高.
- 细胞循环 (分化或血清撤回) 退出后,激酶活性下降.
结论:
- 环林-Cdk复合物的组装是G1阶段细胞增殖途径中的关键步骤.
- 环素E-Cdk2复合体在控制人类细胞G1期间的细胞增殖中发挥着关键作用.
- 这一发现支持了环林-Cdk复合体在真核细胞循环控制中的保留作用.
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.
02:38S-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.
02:15M-Cdk Drives Transition Into Mitosis
Checkpoints throughout the cell cycle serve as safeguards and gatekeepers, allowing the cell cycle to progress in favorable conditions and slow or halt it in problematic ones. This regulation is known as the cell cycle control system.
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
M cyclin...
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
M cyclin...
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.
02:15M-Cdk Drives Transition Into Mitosis
Checkpoints throughout the cell cycle serve as safeguards and gatekeepers, allowing the cell cycle to progress in favorable conditions and slow or halt it in problematic ones. This regulation is known as the cell cycle control system.
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
M cyclin...
Cyclin-dependent kinases, or Cdks, work in concert with cyclins to control cell cycle transitions. M-Cdk, a complex of Cdk1 bound to M cyclin, is a well-known example of this coordinated control that drives the transition from the G2 to the M phase.
M cyclin...