对Cdc48 AAA+ ATPase蛋白展开通路的可视化
Ian Cooney1, Heidi L Schubert1, Karina Cedeno1
1Department of Biochemistry, 15 N. Medical Drive East, University of Utah, Salt Lake City, UT, 84112, USA.
bioRxiv : the preprint server for biology
|April 24, 2024
概括
对于蛋白质质量控制至关重要的Cdc48酶,在基质展开过程中采用了双手交换机制. 结构快照揭示了D1和D2域如何协调转移和展开基板.
科学领域:
- 分子生物学分子生物学
- 生物化学 生物化学
- 结构生物学 结构生物学
背景情况:
- Cdc48是一种六次性AAA+ ATPase,对蛋白质质量控制至关重要.
- 它通过两个ATPase域,D1和D2,堆叠在一个环中发挥作用.
- 了解Cdc48的机制是理解细胞蛋白质平衡的关键.
研究的目的:
- 通过Cdc48.8阐明基板展开的结构基础.
- 研究适配蛋白Shp1在Cdc48功能中的作用.
- 描述蛋白质展开过程中基质转位的机制.
主要方法:
- 从细胞溶解物中净化Cdc48的亲和度,并与Shp1.0复合.
- 确定一组结构,捕捉转位周期的不同状态.
- 结构分析以确定关键的相互作用和结构变化.
主要成果:
- 揭示了连续的结构快照,说明了整个基质转位周期.
- 确定了Shp1和Cdc48.8之间的新型结合接口.
- 支持一个协调的"交换"机制,涉及连续的子单位移动.
结论:
- Cdc48的D1和D2域连续运行,D1在D2.2之前脱离D1.
- 由于其ATP结合和重新结合周期,D2在基质转移和展开中发挥着主导作用.
- 这些发现为Cdc48介导的蛋白质展开提供了详细的机制理解.
相关概念视频
Molecular Chaperones and Protein Folding
17.9K
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...
17.9K
ATP Synthase: Structure
12.3K
ATP synthase or ATPase is among the most conserved proteins found in bacteria, mammals, and plants. This enzyme can catalyze a forward reaction in response to the electrochemical gradient, producing ATP from ADP and inorganic phosphate. ATP synthase can also work in a reverse direction by hydrolyzing ATP and generating an electrochemical gradient. Different forms of ATP synthases have evolved special features to meet the specific demands of the cell. Based on their specific feature, ATP...
12.3K
Protein Folding
8.0K
Proteins are chains of amino acids linked together by peptide bonds. Upon synthesis, a protein folds into a three-dimensional conformation, critical to its biological function. Interactions between its constituent amino acids guide protein folding, and hence the protein structure is primarily dependent on its amino acid sequence.
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
8.0K
The Proteasome Structure
748
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...
748
ATP Synthase: Mechanism
14.5K
In animals, the mitochondrial F1F0 ATP synthase is the key protein that synthesizes ATP molecules through a complex catalytic mechanism. While the nuclear genome encodes the majority of ATP synthase subunits, the mitochondrial genome encodes some of the enzyme's most critical components. The formation of this multi-subunit enzyme is a complex multi-step process regulated at the level of transcription, translation, and assembly. Defects in one or more of these steps can result in decreased...
14.5K
Export of Misfolded Proteins out of the ER
3.6K
After folding, the ER assesses the quality of secretory and membrane proteins. The correctly folded proteins are cleared by the calnexin cycle for transport to their final destination, while misfolded proteins are held back in the ER lumen. The ER chaperones attempt to unfold and refold the misfolded proteins but sometimes fail to achieve the correct native conformation. Such terminally misfolded proteins are then exported to the cytosol by ER-associated degradation or ERAD pathway for...
3.6K


