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Updated: May 29, 2026
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Recombinant Collagen I Peptide Microcarriers for Cell Expansion and Their Potential Use As Cell Delivery System in a Bioreactor Model
Published on: February 7, 2018
Protein export at the ER: loading big collagens into COPII carriers
Vivek Malhotra1, Patrik Erlmann
1ICREA, Barcelona, Spain. vivek.malhotra@crg.eu
The EMBO Journal
|September 1, 2011
Summary
Transporting large molecules like collagens from the endoplasmic reticulum (ER) requires specialized mechanisms beyond standard COPII vesicles. Proteins TANGO1 and cTAGE5 are key to understanding how ER cargo export size is regulated.
Area of Science:
- Cell Biology
- Molecular Biology
- Protein Transport
Background:
- COPII vesicles facilitate the transport of secretory proteins from the endoplasmic reticulum (ER) exit sites.
- Standard COPII vesicles (60-90 nm) are too small for large cargo molecules such as collagens.
Purpose of the Study:
- To investigate the mechanism of export for large cargo molecules from the ER.
- To understand how COPII carrier size is regulated to accommodate different cargo dimensions.
Main Methods:
- The study focuses on the roles of ER exit site-associated proteins TANGO1 and cTAGE5.
- Investigating the involvement of these proteins in collagen transport.
Main Results:
- TANGO1 and cTAGE5 are essential for the transport of collagens, a large secretory cargo.
- These proteins are implicated in regulating the size of COPII carriers.
Conclusions:
- TANGO1 and cTAGE5 are crucial for the export of large cargo, like collagens, from the ER.
- These proteins provide insights into the mechanism of COPII vesicle size regulation for accommodating large cargo.
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