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Visualizing Clathrin-mediated Endocytosis of G Protein-coupled Receptors at Single-event Resolution via TIRF Microscopy
Published on: October 20, 2014
Comparative proteomics of clathrin-coated vesicles.
Georg H H Borner1, Michael Harbour, Svenja Hester
1Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 2XY, England, UK.
The Journal of Cell Biology
|November 23, 2006
Summary
This study identifies 63 proteins in clathrin-coated vesicles (CCVs), revealing 28 novel proteins involved in cellular transport. The findings enhance our understanding of vesicle trafficking and organelle component identification.
Area of Science:
- Cell Biology
- Proteomics
- Molecular Transport
Background:
- Clathrin-coated vesicles (CCVs) are crucial for intracellular cargo transport.
- Understanding the protein composition of CCVs is essential for elucidating transport mechanisms.
Purpose of the Study:
- To conduct the first comparative proteomic analysis of CCVs.
- To identify bona fide CCV proteins and discover novel associated proteins.
Main Methods:
- Isolation of CCV-enriched and mock CCV fractions from HeLa cells.
- Utilized 2D difference gel electrophoresis and isobaric tags for relative and absolute quantification (iTRAQ).
- Mass spectrometry was employed for protein identification and quantification.
Main Results:
- Identified 63 bona fide CCV proteins.
- Discovered 28 proteins not previously associated with CCVs, including SNAREs, AP-3, retromer, BLOC-1 complex subunits, and lysosomal enzymes.
- Identified five novel proteins of unknown function.
Conclusions:
- The study provides a comprehensive proteomic profile of CCVs.
- The developed strategy is applicable for distinguishing genuine organelle proteins from contaminants.
- Advances understanding of protein complexes involved in post-Golgi and endosomal trafficking.
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