Rpn1提供邻近的受体位点,用于蛋白质酶体的基质结合和二化
Yuan Shi1, Xiang Chen2, Suzanne Elsasser1
1Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
概括
研究人员在酵母中发现了第六个蛋白质体泛素受体Rpn1. 在蛋白质降解途径中,Rpn1具有两个结合位点,可识别全方位素和全方位素类域.
科学领域:
- 细胞生物学
- 生物化学
- 分子生物学
背景情况:
- 蛋白质降解对于细胞功能至关重要.
- 蛋白质体是负责蛋白质降解的关键细胞机器.
- 在向蛋白质的蛋白质降解过程中,ubiquitin的识别是关键的步骤.
研究的目的:
- 识别蛋白质组的新型泛素受体.
- 阐明蛋白质体对无素的识别机制.
- 了解Rpn1在基质选择和处理中的作用.
主要方法:
- 酵母遗传学和生物化学
- 蛋白质酶净化和分析
- Rpn1-ubiquitin复合物的X射线晶体学
主要成果:
- 已知的五种蛋白质体基因受体对酵母基因识别无关紧要.
- 一个第六个受体,Rpn1,被识别和特征.
- Rpn1 具有两种独特的结合位点 (T1 和 T2) 对于泛素和泛素类 (UBL) 域.
- T1位点优先结合素48连接的泛素链,调解基质的识别.
- T2 位点结合了二化酶 Ubp6 的 UBL 域,从而促进了 ubiquitin 链的分解.
结论:
- Rpn1是酵母中的新型和必不可少的蛋白质基因受体.
- Rpn1的双位点识别机制对于有效的蛋白质降解至关重要.
- Rpn1集成了基质识别,穿因子相互作用和蛋白质体处理的双化.
相关概念视频
Regulation of the Unfolded Protein Response
3.2K
Inositol-requiring kinase one or IRE1 is the most conserved eukaryotic unfolded protein response (UPR) receptor. It is a type I transmembrane protein kinase receptor with a distinctive site-specific RNase activity. As the binding mechanics of the misfolded proteins with the N-terminal domain of IRE-1 are unclear, three binding models — direct, indirect, and allosteric -- are proposed for receptor activation. Nevertheless, it is known that once a misfolded protein associates with IRE1, it...
3.2K
The Proteasome
2.0K
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...
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...
2.0K
The Proteasome
10.5K
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...
10.5K
Regulated Protein Degradation
9.2K
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...
9.2K
Covalently Linked Protein Regulators
9.9K
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....
9.9K
Directing Proteins to the Rough Endoplasmic Reticulum
18.3K
The organelle-specific signaling sequences direct proteins synthesized in the cytosol to their final destination like ER, mitochondria, peroxisomes, etc. Some of the proteins directed to ER are then trafficked via vesicles to other organelles within the cell or the extracellular environment through the Golgi complex. For example, the rough ER synthesizes soluble proteins for transportation to the lysosomes or secretion out of the cell. It can also synthesize transmembrane proteins that can...
18.3K


