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Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles
Published on: December 31, 2019
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Protein transport by vesicles and tunnels
Ishier Raote1, Vivek Malhotra2,3,4
1Centre for Genomic Regulation, The Barcelona Institute of Science and Technology, Barcelona, Spain ishier.raote@crg.eu.
The Journal of Cell Biology
|February 6, 2019
Summary
Small vesicles were thought to be the only way to transport proteins. This study suggests that cargo, compartment organization, and container fission timing also determine if transport intermediates are vesicles or direct tunnels.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- The established model, Palade's corpus, posits that small vesicles are the exclusive transport mechanism for proteins within the secretory pathway.
- This model assumes stable, distinct compartments and uniform vesicle-mediated transport.
Purpose of the Study:
- To challenge the vesicle-centric view of protein transport in the secretory pathway.
- To propose alternative transport mechanisms influenced by cargo properties and cellular organization.
Main Methods:
- The study is theoretical, re-evaluating existing models and experimental data.
- It employs systems biology principles to analyze transport dynamics.
Main Results:
- Cargo characteristics, spatial arrangement of secretory compartments, and the timing of vesicle fission are critical factors.
- These factors dictate the necessity and form of transport intermediates, which may include vesicles or transient direct tunnels.
Conclusions:
- Protein transport is more complex than solely vesicle-mediated.
- The design of transport intermediates is adaptable, involving both vesicles and direct tunnels, depending on cellular context and cargo.
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