Related Experiment Video
Updated: May 23, 2025
13:08
Quantitative Localization of a Golgi Protein by Imaging Its Center of Fluorescence Mass
Published on: August 10, 2017
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Deep proteomic profiling of the intra-Golgi trafficking intermediates
Farhana Taher Sumya1, Walter S Aragon-Ramirez1, Vladimir V Lupashin1
1Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205.
Molecular Biology of the Cell
|May 21, 2025
Summary
The Conserved Oligomeric Golgi (COG) complex recycles glycosylation machinery via vesicles. COG malfunction disrupts intra-Golgi sorting, highlighting its crucial role in maintaining Golgi function.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Intracellular trafficking utilizes vesicles for cargo transport between cellular compartments.
- The specific role of vesicles in maintaining Golgi apparatus function is not fully understood.
Purpose of the Study:
- To investigate the role of the Conserved Oligomeric Golgi (COG) complex in vesicle-mediated Golgi protein trafficking.
- To elucidate the function of vesicles in preserving Golgi apparatus integrity and function.
Main Methods:
- Acute inactivation of the COG complex in cells.
- Proteomic analysis of vesicles isolated from different Golgi compartments.
- Immunoisolation and characterization of vesicles.
- Analysis of vesicle coats, tethers, and SNAREs.
Main Results:
- Proteomic analysis revealed distinct molecular profiles of vesicles, indicating efficient Golgi protein recycling.
- All detected glycosylation enzymes and sugar transporters were present in intra-Golgi vesicles.
- COG malfunction led to increased glycosylation machinery in vesicles and disrupted intra-Golgi sorting due to impaired vesicle tethering.
- COG-dependent (CCD) vesicles remained functional and could be rerouted to mitochondria expressing Golgi tethers.
Conclusions:
- The COG complex is essential for the COG-dependent, multi-step recycling of the Golgi glycosylation machinery within vesicles.
- Vesicle tethering defects caused by COG depletion disrupt intra-Golgi sorting.
- Specific coats, tethers, and SNAREs coordinate the recycling process orchestrated by the COG complex.
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