蓝藻细菌蛋白VIPP1在脂质双层上形成ESCRT-III类结构
Sichen Pan1, Karin Gries2, Benjamin D Engel3
1Weill Cornell Medicine, Department of Anesthesiology, New York, NY, USA.
Nature structural & molecular biology
|July 26, 2024
概括
塑体1 (VIPP1) 中的囊泡诱导蛋白在脂质双层上形成了状螺旋和多边形. 这是一种ESCRT-III蛋白质.
科学领域:
- 膜生物学 膜生物学
- 蛋白质的结构和动态.
- 细胞生物发生是细胞的生物发生.
背景情况:
- 甲状腺膜生物发生和维护取决于塑体1 (VIPP1) 中的囊泡诱导蛋白质.
- VIPP1属于ESCRT-III超级家族,以形成介导膜变形的丝状结构而闻名.
- 之前的研究揭示了溶液中的VIPP1结构,但缺乏膜相互作用的细节.
研究的目的:
- 阐明VIPP1与脂质膜相互作用的机制.
- 研究VIPP1在膜表面上的动态组装.
- 了解VIPP1结构如何促进膜重塑.
主要方法:
- 使用高速原子力显微镜 (HS-AFM) 可视化支持的脂质双层上的VIPP1组件.
- 电子显微镜 (EM) 数据为溶液中的VIPP1提供了结构洞察力.
- 进行了导线动态和聚合过程的分析.
主要成果:
- 在脂质双层上,VIPP1组装成右侧合螺旋和正规多边形.
- 导线组件通过ESCRT-III类聚合动态发生.
- VIPP1 纤维呈现时针方向的增长,从中央枢纽形成螺旋,从部门外围形成多边形.
- 从阿基米德到对数螺旋的动态转换通过横向化观察到.
结论:
- VIPP1使用类似ESCRT-III的线程组件在膜上形成独特的超分子结构.
- 观察到的VIPP1的动态组合和结构转变对于其在甲状腺膜生物发生中的作用至关重要.
- HS-AFM为VIPP1.1的实时膜相互作用提供了前所未有的洞察力.
相关概念视频
Intralumenal Vesicles and Multivesicular Bodies
3.4K
Intraluminal vesicles (ILVs) are small vesicles 50-80 nm in diameter formed during the maturation of early endosomes. A specialized endosome containing numerous ILVs is called a multivesicular body (MVB). ILVs contain internalized molecules such as antigens, nucleic acids, proteins, and metabolites. Some of these molecules are released from the MVBs inside exosomes and are transported to other cells. Other MVBs contain molecules that are retained in the ILVs and are later degraded within the...
3.4K
Vesicular Tubular Clusters
2.5K
After budding out from the ER membrane, some COPII vesicles lose their coat and fuse with one another to form larger vesicles and interconnected tubules called vesicular tubular clusters or VTCs. These clusters constitute a compartment at the ER-Golgi interface known as ERGIC (Endoplasmic Reticulum Golgi Intermediate Compartment). The ERGIC is a mobile membrane-bound cargo transport system that sorts proteins secreted from ER and delivers them to the Golgi.
With the help of motor proteins such...
With the help of motor proteins such...
2.5K
Cytoskeletal Proteins in Bacteria
3.4K
Bacterial cells were initially considered simple, randomly organized structures lacking a cytoskeleton. However, the discovery of cytoskeleton homologs in bacteria led to the change of this opinion. Bacterial cytoskeletal filaments regulate the cell shape, cell polarity, cell division, and partitioning of plasmids during cell division. It was later discovered that bacterial cytoskeletal proteins, mainly actin and tubulin homologs, are diverse compared to their eukaryotic counterparts. On the...
3.4K
Pinching-off of Coated Vesicles
3.1K
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...
3.1K
Clathrin Coated Vesicles
6.9K
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...
6.9K
Structure of Porins
2.9K
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...
2.9K


