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Cotranslational sorting and processing of newly synthesized proteins in eukaryotes
Martin Gamerdinger1, Elke Deuerling1
1Department of Biology, Molecular Microbiology, University of Konstanz, 78457 Konstanz, Germany.
Trends in Biochemical Sciences
|November 2, 2023
Summary
The nascent polypeptide-associated complex (NAC) sorts proteins during synthesis, ensuring cytonuclear, secretory, and membrane proteins enter the correct biogenesis pathways for proper folding and localization.
Area of Science:
- Molecular Biology
- Cell Biology
- Biochemistry
Background:
- Ribosomes synthesize proteins, but require accessory factors for proper folding and localization.
- Different protein types (cytonuclear, secretory, membrane) necessitate distinct cotranslational processing pathways.
- The nascent polypeptide-associated complex (NAC) is known to interact with ribosomes during protein synthesis.
Purpose of the Study:
- To investigate the specific cotranslational processing steps for different protein classes in eukaryotes.
- To elucidate the role of NAC in sorting nascent polypeptides into their appropriate biogenesis pathways.
Main Methods:
- Analysis of cotranslational interactions between ribosomes and protein biogenesis factors.
- Examination of the function of NAC in directing protein sorting.
- Comparative study of protein processing for cytonuclear, secretory, and membrane proteins.
Main Results:
- Identified distinct cotranslational factor requirements for cytonuclear versus secretory/membrane proteins.
- Demonstrated that NAC acts as a key sorting factor, directing nascent polypeptides.
- Showcased the timely and coordinated action of factors essential for protein biogenesis.
Conclusions:
- NAC plays a crucial role in the cotranslational sorting of proteins into distinct cellular pathways.
- Understanding these pathways is vital for ensuring correct protein maturation, folding, and localization.
- This research provides insights into the fundamental mechanisms of eukaryotic protein biogenesis.
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