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Updated: Jul 14, 2026
09:33
Rapid Isolation of the Mitoribosome from HEK Cells
Published on: October 4, 2018
Reconstructing the evolution of the mitochondrial ribosomal proteome
Paulien Smits1, Jan A M Smeitink, Lambert P van den Heuvel
1Nijmegen Center for Mitochondrial Disorders, Radboud University Nijmegen Medical Center, Geert-Grooteplein-Zuid 10, Nijmegen, The Netherlands.
Nucleic Acids Research
|July 3, 2007
Summary
Mitochondria use their own ribosomes (mitoribosomes) for protein production. This study reveals mitoribosomes evolved from bacterial ancestors, significantly increasing protein content and identifying new human mitochondrial ribosomal proteins (MRPs) as potential diagnostic targets.
Area of Science:
- Molecular Biology
- Evolutionary Biology
- Genomics
Background:
- Mitochondria possess a unique protein synthesis system, the mitochondrial translation system, centered around the mitoribosome.
- Mitoribosomes are essential for producing proteins encoded by the mitochondrial genome.
Purpose of the Study:
- To reconstruct the evolutionary history of the mitoribosomal proteome.
- To identify novel mitochondrial ribosomal proteins (MRPs) and understand their origins.
- To explore the potential of newly identified MRPs as diagnostic targets for mitochondrial disorders.
Main Methods:
- Extensive homology searches and sensitive profile-profile homology searches were employed.
- Comparative analysis of mitoribosomal protein content across diverse eukaryotic lineages.
- Evolutionary reconstruction of the mitoribosomal proteome.
Main Results:
- Mitoribosomes evolved from an alpha-proteobacterial ancestor, with protein content more than doubling in most eukaryotes.
- Significant variations in mitoribosome protein composition exist between different eukaryotes (e.g., mammals vs. yeast).
- Several novel MRPs were identified, some enlarged by functional domains, others originating from duplications or external recruitment. Two novel human MRPs were detected.
Conclusions:
- Mitoribosome evolution is characterized by significant expansion and diversification of protein content.
- Newly identified MRPs, including two novel human ones, offer promising screening targets for mitochondrial oxidative phosphorylation disorders.
- Understanding mitoribosome evolution provides insights into human disease mechanisms.
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