相关实验视频
Updated: May 20, 2026

06:06
In Vitro Analysis of E3 Ubiquitin Ligase Function
Published on: May 14, 2021
序列式E2s驱动在APC目标上的聚比奎丁链组件
Monica C Rodrigo-Brenni1, David O Morgan
1Department of Physiology, University of California, San Francisco, CA 94158, USA.
Cell
|July 17, 2007
概括
亚纳酶促进复合体 (APC) 使用顺序的E2酶,Ubc4和Ubc1,用于全方位链组装. 这种机制对于细胞循环的进展和目标蛋白质的保护体破坏至关重要.
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:
- 亚纳酶促进复合体 (APC/C),一个关键的E3泛基因酶,通过向降解的关键蛋白质来调节细胞循环的进展.
- 通过APC/C和其他E3链酶催化不同泛化反应以形成聚比的精确机制尚不完全理解.
研究的目的:
- 阐明不同E2泛素结合酶在APC/C介导的聚素链形成中的作用.
- 确定与APC/C合作的特定E2酶,并描述它们独特的酶活性.
主要方法:
- 在体外查所有芽酵母E2酶作为APC/C共酶.
- 分析APC/C-E2相互作用和酶活性.
- 缺乏特定E2酶的酵母菌株的功能评估.
主要成果:
- 确定了Ubc4和Ubc1作为芽酵母APC/C.的关键E2合作伙伴.
- 证明Ubc4催化了APC/C标的快速单双化,而Ubc1则调解了K48连接的多双链延伸.
- 在缺乏Ubc1和Ubc4的酵母中观察到线粒APC/C功能丧失.
- 表明人类E2-25K,一个Ubc1同类,也促进APC/C-依赖链延伸.
结论:
- 提出了一种模型,其中不同E2酶 (Ubc4和Ubc1) 的顺序作用驱动APC/C标的K48结合多化.
- 这种顺序的E2机制促进了APC/C基质的及时蛋白质体降解,确保了适当的细胞循环进展.
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...
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...
Post-translational Translocation of Proteins to the RER
A sizable fraction of proteins destined for ER are first synthesized in the cell cytosol and then transported across the ER membrane–a process called post-translational translocation. Similar to cotranslationally translocated proteins, these proteins also use the Sec translocon complex to enter the ER lumen.
Targeting proteins to the ER
Hsp40 and Hsp70 chaperone molecules bind the translated proteins in the cytosol to prevent their folding. The chaperone binding helps to keep the signal...
Targeting proteins to the ER
Hsp40 and Hsp70 chaperone molecules bind the translated proteins in the cytosol to prevent their folding. The chaperone binding helps to keep the signal...
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...
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...

