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Author Spotlight: Oxygen-Independent Assays to Measure Mitochondrial Function in Mammals
Published on: May 19, 2023
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Independent evolution of functionally exchangeable mitochondrial outer membrane import complexes
Daniela G Vitali1, Sandro Käser2, Antonia Kolb1
1Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany.
Elife
|June 21, 2018
Summary
The fungi-specific Mim1/Mim2 complex and trypanosome pATOM36 protein are functional analogs for mitochondrial outer membrane protein insertion. These proteins evolved convergently in distinct eukaryotic lineages.
Area of Science:
- Cell Biology
- Molecular Biology
- Evolutionary Biology
Background:
- Mitochondrial outer membrane (MOM) protein assembly is crucial for organelle function.
- The fungi-specific Mim1/Mim2 complex mediates the insertion of key MOM proteins.
- The functional equivalents of Mim1/Mim2 in other eukaryotes remained unknown.
Purpose of the Study:
- To identify and characterize the functional analogue of the Mim1/Mim2 complex in trypanosomes.
- To investigate the evolutionary origins of MOM protein insertion machinery.
Main Methods:
- Reciprocal genetic complementation experiments between yeast and trypanosomes.
- Analysis of protein complex formation via heterologous expression.
- Assessment of mitochondrial biogenesis, morphology, and protein assembly defects.
Main Results:
- Trypanosome MOM protein pATOM36 functionally complements yeast Mim1/Mim2 deletion mutants.
- Yeast Mim1/Mim2 complex rescues MOM protein assembly defects in pATOM36-deficient trypanosomes.
- pATOM36 and Mim1/Mim2 form stable complexes independently of other proteins.
Conclusions:
- pATOM36 is the functional analogue of the yeast Mim1/Mim2 complex in trypanosomes.
- These proteins represent a case of convergent evolution, arising independently after the divergence of fungi and trypanosomatids.
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