在受管制的内膜蛋白解中基质选择标准
Celine Moser1, Nadja Guschtschin-Schmidt1,2, Mara Silber1
1Institute for Biological Interfaces 4, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
ACS chemical neuroscience
|March 25, 2024
概括
研究人员确定了关键的结构动机,这些动机决定了玛分泌酶 (γ-分泌酶) 如何识别其基质,例如粉样蛋白前体蛋白 (APP),这对于阿尔茨海默病研究至关重要. 这些发现提升了对膜内蛋白酶功能的理解.
科学领域:
- 生物化学 生物化学
- 结构生物学 结构生物学
- 神经科学是一个神经科学.
背景情况:
- 阿尔茨海默病与粉样β (Aβ) 沉积有关,由APP的γ-分泌酶裂解形成.
- 了解γ-分泌酶基质识别至关重要,因为目前关于基质如何进入催化部位的知识有限.
- 该酶在没有共识序列的情况下分裂各种基质,但跨膜域 (TMD) 的突变显著改变了分裂效率.
研究的目的:
- 为了研究规范γ-分泌酶基质识别的结构和动态原理.
- 将已知的γ-分泌酶基质的TMD与非基质进行比较,以确定区分特征.
- 阐明构造灵活性和特定序列动图在基质选择中的作用.
主要方法:
- 对现有的3D结构和γ-分泌酶基质TMDs的动态进行了审查.
- 分析突变基质,其裂变效率发生变化.
- 介绍ITGB1的结构和动态数据,它是一种γ-分泌酶非基质.
- 来自基板和非基板的TMD的比较生物物理分析.
主要成果:
- 在γ-分泌酶基质中确定了三个常见的动机:灵活的TMD,不稳定的裂区域,以及螺旋末端的基本特征.
- 仅仅是形状的灵活性就提高了 APP 和 Notch1.1 等基板的裂解效率.
- 没有单一的图案是唯一的要求;相反,一个可变的组合决定了基质识别.
结论:
- γ-分泌酶对基质的识别是由多种因素的结合决定的,而不仅仅是形状的灵活性.
- 识别的图案提供了关于这种膜内蛋白酶基质特异性的分子基础的见解.
- 这些发现有助于理解APP处理和阿尔茨海默病的潜在治疗策略.
相关概念视频
Mitochondrial Precursor Proteins
2.6K
Mitochondrial precursors are partially unfolded or loosely folded polypeptide chains. Newly synthesized precursors are inhibited from spontaneously folding into their native conformation by the cytosolic chaperones, heat shock proteins 70 (Hsp70), and mitochondrial import stimulation factors (MSFs). Precursors bound to MSFs are guided to the TOM70-TOM37 receptors, while precursors bound to Hsp70 chaperones are targetted to TOM20-TOM22 receptor complexes.
Most of the mitochondrial...
Most of the mitochondrial...
2.6K
The Proteasome
8.6K
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...
8.6K
Regulated Protein Degradation
7.2K
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...
7.2K
Translocation of Proteins into the Mitochondria
3.1K
Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
3.1K
The Proteasome Structure
749
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...
749
ER Retrieval Pathway
3.8K
In the secretory pathway, vesicles transport proteins from one cellular compartment to another in forward transport to deliver the protein to its correct location. Occasionally, misfolded proteins and incorrect proteins escape their original compartments, and a retrieval pathway is used to return the escaped proteins to their original compartment.
The ER uses many checkpoints to prevent the entry of incorrectly folded or a resident protein as cargo onto a transport vesicle. These mechanisms...
The ER uses many checkpoints to prevent the entry of incorrectly folded or a resident protein as cargo onto a transport vesicle. These mechanisms...
3.8K


