Cdc53的目标是酸化的G1环林,通过ubiquitin蛋白质溶解途径降解
A R Willems1, S Lanker, E E Patton
1Programme in Molecular Biology and Cancer Samuel Lunenfeld Research Institute Mount Sinai Hospital, Toronto, Canada.
Cell
|August 9, 1996
概括
发芽的酵母细胞分裂依赖于G1环林. 研究人员发现,Cdc53蛋白向这些循环蛋白进行降解,控制细胞循环的进展.
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:
- 发芽酵母中的细胞分裂是由Cdc28环林依赖激酶调节的,由G1环林 (Cln1,Cln2,Cln3) 激活.
- 对于将环境信号与细胞分裂时间联系起来,G1环林的快速降解至关重要.
研究的目的:
- 为了识别与Cln2相关的蛋白质,一个G1循环.
- 阐明调节Cln2不稳定性和无处不在的机制.
主要方法:
- 使用芽酵母模型分离Cln2相关蛋白质.
- 在体内分析蛋白质相互作用,无化和蛋白质稳定性.
- 研究Cln2酸化在这些过程中的作用.
主要成果:
- 鉴定出Cdc53是一种Cln2结合蛋白.
- 在生物体内,Cdc53对于Cln2的不稳定性和无处不在是必不可少的.
- 需要Cln2酸化才能与Cdc53相互作用,无处不在和降解.
- Cdc53与E2无素结合酶Cdc34.34相互作用.
结论:
- Cdc53是ubiquitin结合酶复合物的组成部分.
- 这种复合物向酸化的G1环林,通过ubiquitin-proteasome途径降解.
- 这种机制为细胞循环进展提供了一个关键的控制点,以响应环境线索.
相关概念视频
Negative Regulator Molecules
Positive regulators allow a cell to advance through cell cycle checkpoints. Negative regulators have an equally important role as they terminate a cell’s progression through the cell cycle—or pause it—until the cell meets specific criteria.
Regulated Protein Degradation
It is vital to regulate the activity of enzymatic as well as non-enzymatic proteins inside the cell. This can be achieved either through creating a balance between their rate of synthesis and degradation or regulating the intrinsic activity of the protein. Both these regulation mechanisms play an essential role in the normal functioning of cells.
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
Inhibition 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...
Separation of Sister Chromatids
At the transition from prophase to metaphase, there is a reduction in cohesion along the chromosomal arms, resulting in the resolution of sister chromatids. However, residual cohesin connections remain to hold the sister chromatids together until the transition from metaphase to anaphase. The residual connection prevents any premature separation of sister chromatids, blocking the risks of aneuploidy within the daughter cells.
At the onset of anaphase, separase, a proteolytic enzyme, is...
At the onset of anaphase, separase, a proteolytic enzyme, is...
Anaphase Promoting Complex
The stepwise destruction of specific proteins is necessary for the progression and completion of the cell cycle. Such proteins are ubiquitinated by ubiquitin ligases and then subsequently destroyed by the proteasome. The SCF (Skp1/Cullin/F-box) and the anaphase-promoting complex (APC) are two important ubiquitin ligases involved in cell cycle progression. While SCF is active throughout the cell cycle, APC gets activated during metaphase to anaphase transition. Cdc20 or Cdh1 binds to APC and...
Anaphase Promoting Complex
The stepwise destruction of specific proteins is necessary for the progression and completion of the cell cycle. Such proteins are ubiquitinated by ubiquitin ligases and then subsequently destroyed by the proteasome. The SCF (Skp1/Cullin/F-box) and the anaphase-promoting complex (APC) are two important ubiquitin ligases involved in cell cycle progression. While SCF is active throughout the cell cycle, APC gets activated during metaphase to anaphase transition. Cdc20 or Cdh1 binds to APC and...


