甲尼丁脱碳酶被26S蛋白质酶降解,没有无处化
Y Murakami1, S Matsufuji, T Kameji
1Department of Nutrition, Jikei University School of Medicine, Tokyo, Japan.
Nature
|December 10, 1992
概括
甲尼丁脱碳酶 (ODC) 降解主要由26S蛋白酶介导. 这种酶复合物促进了ODC分解,即使没有乌比奎,在蛋白质蛋白解中发挥了新的作用.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 酶学 是一种酶学.
背景情况:
- 甲尼丁脱碳酶 (ODC) 是聚胺合成中的关键酶,以其在哺乳动物中的快速循环率而闻名.
- ODC降解由ODC抗酶加速,这是一个由多氨酸诱导的抑制剂,表明选择性蛋白质分解的独特调节机制.
研究的目的:
- 为了确定负责甲尼脱碳酶 (ODC) 降解的特定蛋白酶.
- 调查蛋白质酶在ODC的抗酶依赖性降解中的作用.
主要方法:
- 利用无细胞降解系统研究ODC分解.
- 采用免疫减弱来从细胞提取物中去除蛋白酶.
- 测试了纯化的20S和26S蛋白酶组复合体在ODC降解上的催化活性.
主要成果:
- 细胞提取物中蛋白质体的免疫缺陷导致ATP和抗酶依赖的ODC降解的几乎完全丧失.
- 净化了26S蛋白质组,但没有20S蛋白质组,有效降解了ODC.
- 由26S蛋白酶体降解ODC发生的独立于ubiquitin结合.
结论:
- 26S蛋白酶是负责甲尼脱碳酶降解的主要酶.
- 这一发现表明26S蛋白酶体具有潜在的无素独立的蛋白解功能,扩大了它在细胞蛋白转换中的已知作用.
相关概念视频
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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...
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Protein degradation plays two important roles in the cells. It helps to protect cells from misfolded or damaged proteins before they lead to a...
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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...


