蛋白质酶调节颗粒组合的伴侣介导途径
Jeroen Roelofs1, Soyeon Park, Wilhelm Haas
1Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, Massachusetts 02115, USA.
Nature
|May 5, 2009
概括
三种新型蛋白质,Nas6,Rpn14和HSM3,在酵母体中的蛋白酶体的调节粒子 (RP) 组合中起到关键的陪伴作用. 它们的功能对蛋白质酶体活动至关重要,确保适当的蛋白质降解途径.
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:
- 蛋白酶体是一个重要的细胞机器,负责真核细胞中的蛋白质降解.
- 蛋白酶体的调节粒子 (RP) 促进基质展开和转移到核心粒子 (CP) 中进行降解.
- 目前尚不清楚19个子单元RP的组装路径.
研究的目的:
- 识别和描述参与蛋白酶体调节粒子 (RP) 组装的新型因素.
- 为了阐明这些因素在蛋白质酶生物发生和活动的背景下所起的作用.
- 了解RP陪伴体调节蛋白酶组合的机制.
主要方法:
- 在Saccharomyces cerevisiae中使用生化技术研究了与RP的蛋白质关联.
- 分析了已识别的基因突变对蛋白质酶功能和RP组装的影响.
- 研究了RP陪伴者和RPT ATPase子单元之间的相互作用.
主要成果:
- 确定了三种与RP相关的蛋白质 (Nas6,Rpn14,HSM3),但与全酶无关.
- 证明这些基因的突变导致由于RP组装缺陷而导致蛋白酶功能丧失.
- 表明每个RP陪伴者与特定的Rpt ATPase子单元结合,这表明它在模板组装中的作用.
结论:
- 纳斯6,Rpn14和HSM3作为RP组装的必要伴侣.
- 这些伴侣可以通过控制Rpt C termini对CP的可访问性来调节蛋白质酶组合.
- 伴侣和CP之间的Rpt参与竞争可能解释了在蛋白质酶成熟期间的伴侣释放.
更多相关视频
08:58In Situ Monitoring of Transiently Formed Molecular Chaperone Assemblies in Bacteria, Yeast, and Human Cells
Published on: September 2, 2019
10:24Defining Hsp33's Redox-regulated Chaperone Activity and Mapping Conformational Changes on Hsp33 Using Hydrogen-deuterium Exchange Mass Spectrometry
Published on: June 7, 2018
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...
Molecular Chaperones and Protein Folding
The native conformation of a protein is formed by interactions between the side chains of its constituent amino acids. When the amino acids cannot form these interactions, the protein cannot fold by itself and needs chaperones. Notably, chaperones do not relay any additional information required for the folding of polypeptides; the native conformation of a protein is determined solely by its amino acid sequence. Chaperones catalyze protein folding without being a part of the folded protein.
The...
The...
Molecular Chaperones and Protein Folding
The native conformation of a protein is formed by interactions between the side chains of its constituent amino acids. When the amino acids cannot form these interactions, the protein cannot fold by itself and needs chaperones. Notably, chaperones do not relay any additional information required for the folding of polypeptides; the native conformation of a protein is determined solely by its amino acid sequence. Chaperones catalyze protein folding without being a part of the folded protein.
The...
The...
