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Protein targeting by the twin-arginine translocation pathway
1Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, United Kingdom. crobinson@bio.warwick.ac.uk
Nature Reviews. Molecular Cell Biology
|May 2, 2001
Summary
The twin-arginine translocation (Tat) system transports folded proteins across membranes in bacteria and chloroplasts. Its unique mechanism distinguishes it from other protein transport systems.
Area of Science:
- Cellular biology
- Molecular biology
- Biochemistry
Background:
- The twin-arginine translocation (Tat) pathway is crucial for protein transport across membranes.
- It functions in the thylakoid membrane of chloroplasts and the plasma membrane of bacteria.
- The Tat pathway's primary role is the translocation of fully folded proteins.
Purpose of the Study:
- To investigate the Tat pathway's unique characteristics.
- To understand its distinct mechanism compared to other protein translocases.
Main Methods:
- Identification of three key twin-arginine translocation genes.
- Analysis of the sequences of the proteins encoded by these Tat genes.
Main Results:
- The Tat pathway operates in both chloroplast thylakoid membranes and bacterial plasma membranes.
- Three significant Tat genes and their corresponding protein sequences were identified.
- The identified protein sequences and pathway properties suggest a novel mechanism.
Conclusions:
- The Tat system represents a distinct protein translocation mechanism.
- Its unique features differentiate it significantly from other known protein translocases.
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