拉布GDP分裂抑制剂的结构和突变分析
1Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA.
Nature
|May 2, 1996
概括
牛肉Rab GDP解离抑制剂 (GDI) 的晶体结构揭示了它的双域组织. 通过结构分析和突变遗传学,确定了关键区域,这些区域对于Rab蛋白结合至关重要.
科学领域:
- 结构生物学是结构生物学.
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 拉布GDP分离抑制剂 (GDI) 对于调节囊泡膜运输中的拉布GTPases至关重要.
- 了解GDI的结构对于阐明Rab蛋白回收和功能至关重要.
研究的目的:
- 确定牛类α-GDI的高分辨率晶体结构.
- 确定参与Rab蛋白相互作用的结构特征.
主要方法:
- 用X射线结晶学测定牛类α-GDI的1.81A分辨率结构.
- 局部定向突变发生,以调查保护区域在Rab结合中的作用.
主要成果:
- 该GDI结构包括一个大的多页域I和一个较小的α-螺旋域II.
- 域I与含有FAD的酶具有结构上的相似性.
- 序列保存区域,特别是在顶部,对于Rab结合至关重要.
结论:
- 确定结构为GDI的分子架构和功能提供了洞察力.
- 在GDI内部,特定的保护区域对于其与Rab蛋白的相互作用至关重要,从而促进Rab GTPase调节.
相关概念视频
GTPases and their Regulation
Guanine nucleotide-binding proteins (G-proteins), also known as GTPases, are a superfamily of proteins that regulate many cellular processes, such as cell signaling, vesicular transport, and the regulation of cell shape and motility. Mutation or dysfunction of these proteins can lead to disease. There are around 40,000 known G-proteins that can broadly be classified into two groups ‒ small G-proteins consisting of a single domain and large multi-domain G-proteins.
Large G-proteins, also known...
Large G-proteins, also known...
Rab Proteins
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...
Rab Cascades
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.
Small GTPases - Ras and Rho
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:


