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Membrane translocation of folded proteins
1Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio, USA.
The Journal of Biological Chemistry
|June 7, 2022
Summary
Folded proteins cross cell membranes through various mechanisms, including a newly identified vesicle budding and collapse process. This mechanism may unify our understanding of protein translocation across biological membranes.
Area of Science:
- Cell Biology
- Biochemistry
- Molecular Biology
Background:
- Proteins can translocate across cellular membranes in their folded state.
- This process is crucial for various physiological and pathophysiological functions in both bacterial and eukaryotic cells.
Purpose of the Study:
- To review established and potential systems involving folded protein translocation.
- To discuss proposed mechanistic models for folded protein membrane transport.
- To introduce and evaluate the vesicle budding and collapse mechanism as a unifying model.
Main Methods:
- Literature review of protein translocation systems.
- Analysis of proposed mechanistic models for membrane transport.
- Presentation of evidence for the vesicle budding and collapse mechanism.
Main Results:
- Identified key systems like twin-arginine translocation, unconventional protein secretion, and peroxisomal import.
- Summarized models including pore formation, membrane disruption, and vesicular transport.
- Introduced vesicle budding and collapse as a novel transport mechanism.
Conclusions:
- Folded protein translocation is a widespread biological phenomenon.
- Vesicle budding and collapse offers a potential unifying mechanism for diverse protein translocation processes across membranes.
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