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Protein translocation and turnover in eukaryotic cells
Trends in Biochemical Sciences
|July 1, 1989
Summary
Most eukaryotic proteins are synthesized in the cytoplasm but must translocate to other compartments. Amino acid sequences contain signals directing protein translocation and degradation, predicting cellular localization.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- Most eukaryotic proteins are synthesized in the cytoplasm.
- Many proteins must be translocated to specialized cellular compartments for function.
- This translocation can occur co-translationally or post-translationally.
Purpose of the Study:
- To explore the signals within amino acid sequences that direct protein translocation.
- To investigate how these signals influence protein turnover via proteolytic pathways.
- To identify protein properties that predict cellular localization after translocation.
Main Methods:
- Analysis of amino acid sequences for signal motifs.
- Investigating co- and post-translational translocation mechanisms.
- Correlating protein properties with observed cellular localization.
Main Results:
- Amino acid sequences contain specific signals for protein targeting.
- These signals also influence the protein's susceptibility to degradation.
- Mature protein characteristics can predict their final cellular destination.
Conclusions:
- Protein translocation is a complex process guided by intrinsic sequence signals.
- Cellular localization is a consequence of translocation and influences protein fate.
- Understanding these signals is key to predicting protein function and localization.
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