基于充电拉链机制的TatA转位孔的折叠和自组装
Torsten H Walther1, Christina Gottselig, Stephan L Grage
1Karlsruhe Institute of Technology, Institute of Biological Interfaces, Institute of Organic Chemistry and CFN, Fritz-Haber-Weg 6, 76131 Karlsruhe, Germany.
Cell
|January 22, 2013
概括
像TatA这样的膜蛋白通过静电"充电拉链"自组装成毛孔. 这种机制涉及盐桥形成一个头结构匹配脂质双层厚度孔形成.
科学领域:
- 结构生物学 结构生物学
- 生物物理学的生物物理.
- 分子生物学分子生物学
背景情况:
- 双氨酸转位酶 (Tat) 系统有助于蛋白质穿过膜的运输.
- 塔塔复合体对于形成转位孔至关重要.
- 了解膜蛋白的自我组装对于细胞功能至关重要.
研究的目的:
- 提出一个新的机制,用于折叠和自组装的塔塔综合体.
- 为了研究电静相互作用在膜蛋白组合中的作用.
- 探索这种机制对其他膜蛋白的概括性.
主要方法:
- 分子动力学模拟以评估硬体可行性.
- 蛋白质子单元结构的分析,包括跨膜段,两螺旋 (APH) 和C端密集充电区域 (DCR).
- 使用充电突变物监测单体-寡合体平衡的实验验证.
主要成果:
- 一个小小的东西.
- 结论 结论 结论 结论
结论:
- 静电电静电学 静电电静电学
- 拟议的 拟议的 拟议的
- 这种机制为各种膜蛋白的组装提供了洞察力,包括TisB,dermcidin和E(RNS).
相关概念视频
Pinching-off of Coated Vesicles
Vesicle budding is orchestrated by distinct cytosolic proteins such as adaptor proteins, coat proteins, and GTPases. To initiate vesicle budding, membrane-bending proteins containing crescent-shaped BAR domains bind to the lipid heads in the bilayer and distort the membrane to form a protein-coated vesicle bud. Adaptors proteins such as AP2 for clathrin-coated vesicles can nucleate on the deformed membrane. Finally, coat proteins such as clathrin or COPI and COPII assemble into a coat forming...
Protein Translocation Machinery on the ER Membrane
The translocon complex situated on the ER membrane is the main gateway for the protein secretory pathway. It facilitates the transport of nascent peptides into the ER lumen and their insertion into the ER membrane.
Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the translocon complex.
Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the translocon complex.
Clathrin Coated Vesicles
Clathrin-coated vesicles use endocytosis to transport receptors and lysosomal hydrolases from the Golgi to the lysosome in the late secretory pathway. Clathrin-mediated endocytosis was the first described endocytic process, and Clathrin-coated vesicles remain one of the most well-studied transport vesicles. The molecular machinery that generates clathrin-coated vesicles comprises over 50 proteins that precisely coordinate vesicle formation. Cell surface receptors concentrated in indented sites...
Structure of Porins
Mitochondria, chloroplasts, and gram-negative bacteria have transmembrane, beta-barrel proteins called porins to mediate the free diffusion of ions and metabolites across the membrane. Mitochondrial porin precursors contain conserved amino acid sequences called beta signals at their C-terminal. Beta signals have a motif of PoXGXXHyXHy (Po-Polar, X-Any amino acid, G-Glycine, Hy-LargeHydrophobic), which are crucial for precursor recognition to initiate precursor assembly. Beta-barrel precursors...
Coat Assembly and GTPases
Vesicles incorporate different coat protein subunits in different cell locations, which changes the properties of the coat, such as the shape and geometry of the transport vesicles. Thus, vesicle coat proteins also play a significant role in cargo selection.
Coat assembly depends on the local availability of phosphatidylinositol phosphates or PIPs and GTP-binding proteins. Adaptor proteins, which link the coat proteins to the membrane, bind to these PIPs and play a crucial role in controlling...
Coat assembly depends on the local availability of phosphatidylinositol phosphates or PIPs and GTP-binding proteins. Adaptor proteins, which link the coat proteins to the membrane, bind to these PIPs and play a crucial role in controlling...
Energy to Drive Translocation
Mitochondrial protein import is powered by two distinct energy sources: ATP hydrolysis and electrochemical potential across the inner membrane. Newly synthesized precursors are bound by cytosolic chaperones of the Hsp70 family, which guide them to the import receptors on the mitochondrial surface. Utilizing the energy of ATP hydrolysis, Hsp70 chaperones transfer these precursors to the TOM receptors on the mitochondrial outer membrane.
Generally, polypeptides are unfolded by two distinct...
Generally, polypeptides are unfolded by two distinct...


