戈尔金连带定义了COPI囊泡的子群
Jörg Malsam1, Ayano Satoh, Laurence Pelletier
1Department of Cell Biology, Ludwig Institute for Cancer Research, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520-8002, USA.
概括
戈尔金-84和CASP蛋白质在戈尔吉装置中充当带,与p115-golgin不同. 这种golgin-84-CASP结合剂调解了酶的逆向运输到内质网膜.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 蛋白相互作用 蛋白相互作用
背景情况:
- 戈尔金蛋白质是卷曲-卷曲蛋白质,参与了Golgi内部的运输.
- 在囊泡结合中,p115-golgin结合的特征很好.
- 其他高尔金的具体作用,如高尔金-84,仍然不太清楚.
研究的目的:
- 为了描述golgin-84-CASP结合复合物的特征.
- 为了确定与golgin-84-CASP相关的囊泡和货物的类型.
- 为了调查golgin-84-CASP在Golgi运输通道中的作用.
主要方法:
- 戈尔金-84-CASP复合物的生物化学特征.
- 分析被绳索束的囊泡组成.
- 微注射实验以评估运输抑制.
主要成果:
- 戈尔金-84-CASP与p115-golgin结合的囊泡有所区别.
- 这些囊泡缺乏p24蛋白质,并含有酶,而不是前级载荷.
- 微注射的golgin-84或CASP抑制了Golgi酶向ER的运输,表明逆行功能.
结论:
- 戈尔金-84-CASP与戈尔吉河内的逆行运输有关.
- 这一发现扩大了我们对戈尔吉走私机制的理解.
- 戈尔金可以调节Golgi内部流动模式和蛋白质局部化.
相关概念视频
COP Coated Vesicles
Membrane-enclosed structures called vesicles transport proteins and lipids across the cell. The vesicles derive their cargo from the plasma membrane, Golgi, ER, or endosome. Coated vesicles are spherical, protein-coated carriers with a 50–100 nm diameter that mediate bidirectional transport between the ER and the Golgi. The distribution of proteins between the ER and Golgi complex is dynamic and is maintained by different coated vesicles. Their formation is driven by the assembly of different...
Pinching-off of Coated Vesicles
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...
Coat Assembly and GTPases
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...
Vesicular Tubular Clusters
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...
GPI Anchoring of Proteins in the ER Membrane
GPI-anchoring is a post-translational, reversible protein modification that is ubiquitous in eukaryotes. Such proteins are primarily present on the exoplasmic leaflet of the plasma membrane.
GPI-anchor structure
A sequence of 11 enzymatic reactions results in the synthesis of the complete GPI anchor consisting of a hydrophobic and a hydrophilic portion. The hydrophobic portion comprises phosphatidylinositol, while the hydrophilic part comprises polar groups like phosphoethanolamine,...
GPI-anchor structure
A sequence of 11 enzymatic reactions results in the synthesis of the complete GPI anchor consisting of a hydrophobic and a hydrophilic portion. The hydrophobic portion comprises phosphatidylinositol, while the hydrophilic part comprises polar groups like phosphoethanolamine,...
Protein Translocation Machinery on the ER Membrane
The translocon complex situated on the ER membrane is the main gateway for the protein secretory pathway. It facilitates the transport of nascent peptides into the ER lumen and their insertion into the ER membrane.
Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the translocon complex.
Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the translocon complex.


