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Assessment of Submitochondrial Protein Localization in Budding Yeast Saccharomyces cerevisiae
Published on: July 19, 2021
Mosaic origin of the mitochondrial proteome
Radek Szklarczyk1, Martijn A Huynen
1Radboud University Nijmegen Medical Centre, CMBI/NCMLS, Nijmegen, The Netherlands.
Proteomics
|November 17, 2010
Summary
Mitochondrial proteomes are a mosaic of endosymbiotic, eukaryotic, and archaeal proteins. Complex protein systems evolved from endosymbiosis, while enzymes show diverse origins, reflecting evolutionary pressures.
Area of Science:
- Evolutionary biology
- Cell biology
- Biochemistry
Background:
- Mitochondrial origin from an alpha-proteobacterium is known.
- Host cell, endosymbiont complexity, and proto-mitochondrion evolution are debated.
- Mitochondrial proteome evolution is under active investigation.
Purpose of the Study:
- Review inferred original composition of mitochondrial proteomes.
- Analyze the subsequent evolution of essential mitochondrial systems.
- Discuss the origins and evolutionary trajectories of mitochondrial proteins.
Main Methods:
- Literature review of inferred mitochondrial proteome composition.
- Analysis of protein origins: endosymbiotic, eukaryotic-specific, and archaeal/bacterial.
- Application of the complexity hypothesis to protein evolution.
Main Results:
- Mitochondrial proteomes comprise 15-45% endosymbiotic, 40% eukaryotic-specific, and 15% archaeal/bacterial proteins.
- Protein complexes are primarily endosymbiotic in origin but expanded with eukaryotic proteins.
- Mitochondrial enzymes exhibit both proteobacterial and non-proteobacterial origins.
Conclusions:
- Mitochondrial proteome composition is an evolutionary mosaic.
- The complexity hypothesis explains the limited horizontal gene transfer in large protein complexes.
- Subcellular compartments of mitochondrial proteins remain conserved despite gene transfer events.
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