一个神秘的蛋白质酶通过蛋白质酶体对双化和降解进行配对
1Department of Biochemistry, University of Iowa, 51 Newton Road, Iowa City, Iowa 52242, USA.
Nature
|September 28, 2002
概括
26S蛋白酶体降解蛋白质,需要去除无素. POH1,一个19S子单元,作为一种新的Zn(2+) 依赖蛋白酶,用于二维基因化,对于蛋白质体降解和细胞活力至关重要.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 26S蛋白酶体是真核生物中细胞内蛋白质降解的主要机制.
- 蛋白质降解需要去除无素链,这一过程对于基质转移到20S核心至关重要.
研究的目的:
- 为了阐明在蛋白质体降解过程中杜比基化的机制和重要性.
- 为了确定负责从蛋白酶体基板中去除乌比奎的特定子单元.
主要方法:
- 研究了POH1/Rpn11亚单元在脱化中的作用.
- 在实验室中评估了受损的二维基化对蛋白质降解率的影响.
- 检查了酵母中的二维化缺陷的致命性.
主要成果:
- 确定POH1 (酵母中的Rpn11) 作为负责19S调节复合体内基质二维基因化的子单元.
- 证明无法去除乌比奎可以限制蛋白质体降解的速度.
- 表明,在酵母中,二氧化的缺陷是致命的.
- 描述POH1作为一个Zn(2+) 依赖的蛋白酶,与其他已知的氨酸蛋白酶脱化酶 (DUBs) 区别.
结论:
- POH1对于与降解相关的二维基化是必不可少的.
- POH1代表了一种新型的金属蛋白质酶解化酶类.
- 通过POH1有效的二维基化对蛋白质体功能和细胞存活至关重要.
相关概念视频
The Proteasome
Eukaryotic cells can degrade proteins through several pathways. One of the most important amongst these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
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...
The Proteasome
Eukaryotic cells can degrade proteins through several pathways. One of the most important amongst these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. A series of enzymes carry out the ubiquitination of the target proteins - E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3...
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...
The Proteasome
Eukaryotic cells can degrade proteins through several pathways. One of the most important among these is the ubiquitin-proteasome pathway. It helps the cell eliminate the misfolded, damaged, or unwarranted cytoplasmic proteins in a highly specific manner.
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 (ubiquitin...
In this pathway, the target proteins are first tagged with small proteins called ubiquitin. This involves participation of a series of enzymes including— E1 (ubiquitin-activating enzyme), E2 (ubiquitin-conjugating enzyme), and E3 (ubiquitin...
The Proteasome Structure
The ubiquitin-proteasome pathway is a well-known mechanism utilized by eukaryotic cells to remove cytoplasmic proteins that are misfolded, damaged, or no longer needed. In this pathway, the protein that needs to be eliminated undergoes a process called ubiquitination, where a chain of ubiquitin molecules is attached to the 48th lysine residue of the target protein. This ubiquitin modification helps the proteasome distinguish between a target protein and a healthy protein.
The proteasome is an...
The proteasome is an...


