免疫和构成性蛋白质体在它们降解无处不在的蛋白质的能力上没有区别
James A Nathan1, Valentina Spinnenhirn, Gunter Schmidtke
1Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
Cell
|March 5, 2013
概括
免疫蛋白质酶体不会比构成性蛋白质酶体更快地降解无化蛋白质. 我们的研究结果与以前关于免疫蛋白酶体功能和细胞对干扰素-的反应的研究相矛盾.
科学领域:
- 细胞生物学 细胞生物学
- 免疫学 免疫学 免疫学
- 蛋白质体功能 蛋白质体功能
背景情况:
- 免疫蛋白酶体是专门的蛋白酶体复合体,参与抗原处理.
- 干扰素- (IFNγ) 影响蛋白酶体活性和免疫反应.
- 之前的研究表明,免疫蛋白酶在降解无处不在的蛋白质方面具有独特的作用.
研究的目的:
- 通过免疫蛋白质酶对构成性蛋白质酶的降解率研究无处不在的蛋白质.
- 检查IFNγ治疗对多比基因合物水平的影响.
- 评估免疫蛋白质体在预防细胞内包容和实验性自身免疫脑膜炎 (EAE) 中的作用.
主要方法:
- 通过纯化的26S构成体和免疫蛋白质酶体对无素蛋白降解的比较分析.
- 在细胞中IFNγ治疗后评估聚比基因合物水平.
- 在免疫蛋白酶体缺陷模型中评估细胞内包容形成和EAE严重程度.
主要成果:
- 在IFNγ治疗后,聚比基因合物没有显示过渡性积累.
- 免疫蛋白酶并没有阻止细胞内含的形成,也没有防止EAE.
- 净化的构成性和免疫蛋白酶体表现出类似的结合和降解率与乌比奎丁合物.
结论:
- 免疫蛋白质酶体不会比构成性蛋白质酶体更有效地降解无化蛋白质.
- 与此前的报道相反,免疫蛋白酶体对细胞内含体或EAE没有保护作用.
- 虽然免疫蛋白酶增强MHC I类的生成,但它们在无处不在的蛋白质降解中的作用与构成性蛋白质酶相似.
相关概念视频
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
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...
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...
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...
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...
Covalently Linked Protein Regulators
Proteins can undergo many types of post-translational modifications, often in response to changes in their environment. These modifications play an important role in the function and stability of these proteins. Covalently linked molecules include functional groups, such as methyl, acetyl, and phosphate groups, and also small proteins, such as ubiquitin. There are around 200 different types of covalent regulators that have been identified.
These groups modify specific amino acids in a protein.
These groups modify specific amino acids in a protein.


