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Published on: January 11, 2017
Protein translocation across biological membranes
William Wickner1, Randy Schekman
1Department of Biological Chemistry, Dartmouth Medical School, 7200 Vail Building, Hanover, NH 03755-3844, USA. Bill.Wickner@Dartmouth.edu
Science (New York, N.Y.)
|December 3, 2005
Summary
Protein targeting and translocation across organelle membranes are crucial for cellular function. This review covers 35 years of progress in understanding how proteins reach their destinations and identifies key questions for future research.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Cells contain distinct subcellular compartments with specialized protein compositions.
- Protein synthesis occurs primarily in the cytosol, mitochondria, and chloroplasts.
- Efficient protein targeting and translocation across organelle membranes are essential for cellular organization.
Purpose of the Study:
- To review the progress in understanding protein targeting and translocation mechanisms over the past 35 years.
- To highlight key unresolved questions and future research directions in the field.
Main Methods:
- Literature review of studies on protein targeting and translocation.
- Analysis of mechanisms for protein recognition, translocation, and membrane insertion.
- Discussion of the role of protein factors and lipid environment in transport.
Main Results:
- Significant advancements have been made in understanding protein targeting signals and translocation machinery.
- Mechanisms for substrate specificity, polypeptide chain translocation, and transmembrane protein insertion are increasingly understood.
- The coordination of protein synthesis, folding, and translocation has been elucidated.
Conclusions:
- Decades of research have greatly advanced our knowledge of protein transport within cells.
- Further investigation is needed to fully resolve complex mechanisms, including substrate recognition and membrane integration.
- Future research will focus on the interplay between protein synthesis, folding, and translocation, and the role of the lipid environment.
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