相关实验视频
Updated: May 11, 2025

12:15
In Vitro Polymerization of F-actin on Early Endosomes
Published on: August 28, 2017
8.9K
识别Rab GTPase激活蛋白对于管状内分泌体形成所需的蛋白质
Shumpei Nakashima1, Mitsunori Fukuda1
1Laboratory of Membrane Trafficking Mechanisms, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan.
Traffic (Copenhagen, Denmark)
|April 17, 2025
概括
研究人员确定了四种GTPase激活蛋白 (GAPs),这些蛋白调节了管状内分泌体的形成. 这些Rab-GAPs,包括TBC1D10B,对于维持管状内体结构和货物回收至关重要.
科学领域:
- 细胞生物学 细胞生物学
- 分子和细胞生物学分子和细胞生物学.
- 细胞内核和细胞内贩运.
背景情况:
- 克拉特林独立的内细胞分裂涉及管状内体,用于货物回收.
- 拉布小GTPases,如Rab22A,调节管状内体结构和功能.
- 拉布GTPase活性是由关氨酸核酸交换因子 (GEFs) 和GTPase激活蛋白 (GAPs) 调节的.
研究的目的:
- 为了确定参与管状内分泌体形成的Rab-GAPs.
- 研究特定Rab-GAPs在调节Rab22A活动和管状内分泌体中的作用.
主要方法:
- 在HeLa细胞中对TBC/Rab-GAP进行全面查.
- 在Rab-GAPs的敲击或过度表达后,分析管状内体结构.
- 评估活性Rab22A水平和Rab22A阳性早期内分体大小.
主要成果:
- 确定了四种Rab-GAPs (TBC1D10B,TBC1D18,TBC1D22B,EVI5) 作为管状内分泌体形成的调节者.
- 这些Rab-GAPs的淘汰或过度表达以GAP活动依赖的方式损害了管状内分泌体结构.
- 确定TBC1D10B是可能的Rab22A-GAP,减少活跃的Rab22A和早期内分体大小.
结论:
- 在管状内分泌体的形成和维持中,Rab-GAPs起着至关重要的作用.
- 均衡的GTPase循环,涉及GEF和GAP,对于管状内分体调节至关重要.
- 这些发现确定了内体贩运的新型调节者,并提供了有关Rab蛋白功能的见解.
相关概念视频
Rab Cascades
2.6K
Rab GTPases act in a regulated cascade during membrane fusion, helping the lipid bilayers mix. The Rab family of proteins are active when bound to GTP, and inactive when bound to GDP. Hence, they act as guanine nucleotide-dependent molecular switches. Rab-GTP recognizes and binds to long or short-range tethering proteins to capture the target vesicle. These tethers coordinate with SNAREs on the vesicle and the target membrane to assemble the trans SNARE complex that locks the mixing bilayers.
2.6K
Rab Proteins
3.8K
Rab proteins constitute the largest family of monomeric GTPases, of which 70 members are present in humans. Rab proteins and their effectors regulate consecutive stages of vesicle transport such as vesicle transport, docking, and fusion to the correct recipient membrane.
Rab proteins switch between a cytosolic, GDP-bound inactive state and a membrane-anchored, GTP-bound active state. By themselves, Rabs show slow rates of GDP/GTP exchange and GTP hydrolysis. Thus, Rab proteins are considered...
Rab proteins switch between a cytosolic, GDP-bound inactive state and a membrane-anchored, GTP-bound active state. By themselves, Rabs show slow rates of GDP/GTP exchange and GTP hydrolysis. Thus, Rab proteins are considered...
3.8K
The Early Endosome: Endocytosis of Transferrin
3.2K
Essential proteins such as insulin or low-density lipoprotein (LDL) and micronutrients such as iron enter a eukaryotic cell through receptor-mediated endocytosis. Subsequently, the early endosomes fuse with the vesicles containing such receptor-ligand complexes and play a vital role in sorting the incoming ligands and receptors. While the ligands are either degraded inside the vesicle or released into the cytosol, their receptors are returned to the plasma membrane for further rounds of...
3.2K
Coat Assembly and GTPases
3.4K
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...
3.4K
Small GTPases - Ras and Rho
3.8K
Ras and Rho are small monomeric GTPases that act downstream of receptor tyrosine kinase (RTK) and regulate various cellular processes. These GTPases switch between active and inactive states by binding to guanine nucleotides.
Three regulatory proteins control their activity:
Three regulatory proteins control their activity:
3.8K
Recycling Endosomes and Transcytosis
2.5K
The recycling endosome, also known as the endosomal recycling compartment (ERC), is a part of the slow-recycling process of the endocytic pathway. Molecules internalized through receptor-mediated endocytosis are either degraded in the lysosomes or are recycled to the plasma membrane through the fast- or slow-recycling route.
The recycling endosome is not a single organelle but an extensively tubulated network of recycling pathways. It functions in storing molecules or transporting them across...
The recycling endosome is not a single organelle but an extensively tubulated network of recycling pathways. It functions in storing molecules or transporting them across...
2.5K

