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Evolution: 'Millefoglie' origin of mitochondrial cristae.
Paul A M Michels1, Michael L Ginger2
1Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3FL, UK.
Current Biology : CB
|March 28, 2023
Summary
A protein complex forming mitochondrial cristae in eukaryotes also drives intracytoplasmic membrane formation in alphaproteobacteria. This discovery reveals the bacterial origins of mitochondrial cristae biogenesis.
Area of Science:
- Cell Biology
- Microbiology
- Evolutionary Biology
Background:
- Alphaproteobacteria possess complex intracytoplasmic membranes, structurally resembling millefoglie pastries.
- Mitochondrial cristae, internal membrane structures within mitochondria, are crucial for cellular respiration.
Purpose of the Study:
- To investigate the molecular machinery responsible for the formation of striated intracytoplasmic membranes in alphaproteobacteria.
- To determine if this machinery shares ancestry with the proteins involved in mitochondrial cristae biogenesis.
Main Methods:
- Comparative genomics and proteomics to identify homologous protein complexes.
- High-resolution microscopy to visualize membrane structures and protein localization.
Main Results:
- A protein complex homologous to the one forming mitochondrial cristae was identified in alphaproteobacteria.
- This bacterial protein complex was shown to drive the formation of intracytoplasmic membranes.
Conclusions:
- The biogenesis of mitochondrial cristae has ancient bacterial origins.
- The identified protein complex represents a key evolutionary link between bacterial membrane formation and mitochondrial structure.
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