相关实验视频
Updated: Jul 13, 2026

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In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones
Published on: July 25, 2019
基于一种类似于ubiquitin的蛋白质硫开关的基础,可以切换E1-E2亲和力
Danny T Huang1, Harold W Hunt, Min Zhuang
1Howard Hughes Medical Institute, St Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
Nature
|January 16, 2007
概括
这项研究揭示了ubiquitin-like protein (UBL) 结合酶是如何通过一种硫机制来切换结合亲和关系的. 这种形状变化驱动了UBL修改路径中的连续步骤.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 分子细胞生物学 分子细胞生物学
背景情况:
- 类似乌比奎丁的蛋白质 (UBLs) 通过动态的E1-E2-E3酶级联进行修饰.
- E1酶通过腺化激活UBLs,形成对随后的结合步骤至关重要的酸中间体.
研究的目的:
- 阐明在人类NEDD8路径内UBL激活和转移的结构机制.
- 了解酶基质相互作用和构造变化如何驱动UBL结合级联.
主要方法:
- 报告了被困的UBL激活复合体的结构分析.
- 使用了一个含有NEDD8 E1酶 (APPBP1-UBA3) 的复合物,两个NEDD8分子,一个不活跃的E2酶 (Ubc12) 和MgATP.
主要成果:
- 确定了一个调节E1-E2亲缘关系的"thioester开关"机制.
- 揭示了两个依赖于NEDD8与E1的硫结合的E2结合位点,其中一个由E1形状变化揭示.
- 证明了NEDD8转移到E2会诱导E1的形态逆转,从而促进产品的释放.
结论:
- 结合酶间的铁链接的转移驱动着形状变化,并改变了相互作用网络.
- 这种机制对于推动UBL合级联中的连续步骤至关重要.
相关概念视频
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.
Protein Complexes with Interchangeable Parts
Groups of proteins may form a complex where each protein in this complex has a different role in the overall execution of the complex’s function. Often some of the proteins in the complex can be replaced by a closely related variant to give a complex that contains many of the same components yet is functionally distinct.
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
The SCF ubiquitin ligase is a protein complex of five individual proteins. This complex attaches ubiquitin to other target proteins to mark them for degradation. In order to...
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...

