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Co-Translational Protein Folding and Sorting in Chloroplasts
Fabian Ries1, Claudia Herkt1, Felix Willmund1
1Molecular Genetics of Eukaryotes, University of Kaiserslautern, Paul-Ehrlich-Strasse 23, 67663 Kaiserslautern, Germany.
Plants (Basel, Switzerland)
|February 13, 2020
Summary
This review explores co-translational factors in plant chloroplasts, focusing on their roles in protein folding and translocation. These factors are crucial for maintaining protein homeostasis and enabling photosynthesis.
Area of Science:
- Plant Biology
- Molecular Cell Biology
- Biochemistry
Background:
- Cellular proteome homeostasis requires continuous protein renewal and efficient synthesis.
- Higher eukaryotes utilize millions of ribosomes for protein synthesis, necessitating robust folding and sorting mechanisms.
- Plant chloroplasts also perform protein synthesis for essential photosynthetic and metabolic functions.
Purpose of the Study:
- To review current knowledge on co-translationally binding factors in plant chloroplasts.
- To discuss the function of these factors in protein folding.
- To examine their role in ribosome translocation to thylakoid membranes.
Main Methods:
- Literature review of co-translational protein targeting in plant chloroplasts.
- Analysis of the roles of ribosome-associated factors.
- Discussion of protein biogenesis pathways.
Main Results:
- Co-translational factors bind nascent polypeptides emerging from the ribosome.
- These factors facilitate protein folding and prevent aggregation.
- They mediate the translocation of ribosome-nascent chain complexes to target membranes, such as thylakoids.
Conclusions:
- Co-translational factors are essential for efficient protein biogenesis in plant chloroplasts.
- Their function is critical for the assembly of photosynthetic complexes.
- Understanding these factors aids in comprehending chloroplast protein homeostasis and function.
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