相关实验视频
Updated: Jul 20, 2026

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Comparing the Affinity of GTPase-binding Proteins using Competition Assays
Published on: October 8, 2015
参与GTP结合的"G"蛋白通过戈尔吉堆进行运输
P Melançon1, B S Glick, V Malhotra
1Department of Biochemistry, Stanford University, California 94305.
Cell
|December 24, 1987
概括
关氨酸核酸结合蛋白 (G蛋白) 调节了戈尔基蛋白的运输. GTP gamma S通过阻断受体戈尔吉膜来抑制这种运输,从而影响关键的融合步骤.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 蛋白质运输机制 蛋白质运输机制
背景情况:
- 戈尔吉装置对于修改和分类蛋白质至关重要.
- 细胞内蛋白质运输依赖于戈尔吉区间之间的囊泡贩运.
- 关氨酸核酸结合蛋白 (G蛋白) 是已知的细胞信号传递和贩运的调节者.
研究的目的:
- 研究G蛋白在戈尔吉内部蛋白质运输中的作用.
- 阐明GTP马S影响戈尔吉函数的特定机制.
- 为了确定由GTP gamma S.抑制的囊泡介导输送的阶段.
主要方法:
- 利用无细胞系统研究戈尔吉区间之间的蛋白质运输.
- 采用GTP gamma S和化物/离子来抑制运输.
- 进行了预化实验,以区分供体和接受体膜作用.
- 应用电子显微镜可视化戈尔吉结构和囊泡动力学.
主要成果:
- GTP gamma S 无法逆转地抑制了戈尔吉区间之间的蛋白质运输.
- 化物/离子模仿了抑制作用,表明G蛋白参与.
- 抑制需要细胞结合因子,并特别影响受体戈尔吉膜.
- 在囊泡附着和融合之间的处理步骤被确定为目标.
- 电子显微镜显示,非克拉特林涂层的芽和囊泡增加了5倍.
结论:
- G 蛋白对于调节通过高尔基堆的蛋白质运输至关重要.
- GTP gamma S通过干扰受体膜上的囊泡融合来抑制戈尔吉运输.
- 这些发现突出了G蛋白信号传递在维护戈尔吉隔间完整性和功能方面的关键作用.
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...
Coat Assembly and GTPases
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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...
Golgi Matrix Proteins
Golgi matrix proteins are a group of highly dynamic proteins that maintain the stacked structure of Golgi. These proteins adapt to rapid morphological changes of the Golgi during the cell cycle. During cell division, mild proteolysis removes these connections resulting in Golgi unstacking. In The daughter cells, these proteins help reassemble the unstacked Golgi.
One of the first identified Golgi matrix proteins was GM130, a rod-like protein located in the cis-Golgi. Subsequently, many Golgi...
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Transport Across the Golgi
While it is unclear how molecules move between adjacent Golgi cisternae, it is apparent that the molecules move from cis- cisterna, the entry face, to the trans- cisterna, the exit face. Experiments initially suggested vesicles that bud from one cisterna and fuse with the next cisterna to transport proteins between the cisternae. This vesicular transport model describes the Golgi apparatus as a relatively static structure with a unique enzyme composition in each cisterna. Molecules are...
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...
Activation and Inactivation of G Proteins
Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high affinity and are together...

