一种可光分离的拉巴胺结合物,用于对小GTPase活性进行时空控制
Nobuhiro Umeda1, Tasuku Ueno, Christopher Pohlmeyer
1Department of Cell Biology, Center for Cell Dynamics, Johns Hopkins University, Baltimore, Maryland 21205, USA.
Journal of the American Chemical Society
|December 15, 2010
概括
科学家们创造了一种新的方法,可以使用光来控制信号分子. 这种技术允许精确的,像Rac这样的蛋白质的亚细胞激活,有助于研究动态细胞内信号.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 细胞内信号通路对于细胞功能至关重要.
- 控制信号分子的时空活动对于理解细胞过程至关重要.
- 现有的控制信号分子活动的方法在精度和范围上都有局限性.
研究的目的:
- 开发一种用于空间时空控制信号分子活动的新方法.
- 为了实现信号分子的细胞下局部激活.
- 为了能够精确地调查动态细胞内信号事件.
主要方法:
- 合成了一种新型的光拉巴胺衍生物.
- 利用紫外线照射诱导FKBP和FRB蛋白质的二元化.
- 使用空间限制的紫外线辐射进行有针对性的激活.
- 监测小GTPases的激活,特别是Rac.
主要成果:
- 照相中的拉巴胺衍生物使得FKBP和FRB在UV暴露后能够快速二元化.
- 局限于空间的紫外线辐射导致Rac.的细胞下局部激活.
- 证明精确控制细胞内信号分子的激活.
结论:
- 开发的光拉巴胺素系统为信号的时空控制提供了一个强大的工具.
- 这种技术允许细胞内的蛋白质高度局部激活.
- 为研究高分辨率的动态细胞内信号事件提供了显著的进步.
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...
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:
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...
Conservative Site-specific Recombination and Phase Variation
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
The recognition sites for Cre recombinase called LoxP...
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.


