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The plant mitochondrial protein import apparatus - the differences make it interesting
Monika W Murcha1, Yan Wang1, Reena Narsai2
1ARC Centre of Excellence in Plant Energy Biology, Bayliss Building M316, The University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009, Australia.
Biochimica Et Biophysica Acta
|October 2, 2013
Summary
Mitochondrial protein import mechanisms show high conservation between plants and yeast. Plant-specific gene expansions in the import apparatus are crucial for seed viability and germination.
Area of Science:
- Mitochondrial biology
- Cellular and molecular biology
Background:
- Mitochondria are vital for eukaryotic cell life and death.
- Studying single-celled models like yeast offers insights into mitochondrial function across diverse organisms.
- Evolutionary divergence has led to significant differences in mitochondrial functions.
Purpose of the Study:
- To review and compare mitochondrial protein import mechanisms in plants and yeast.
- To identify conserved and divergent aspects of the mitochondrial protein import apparatus.
- To explore interactions between the import machinery and the respiratory chain.
Main Methods:
- Comparative review of existing research on mitochondrial protein import.
- Analysis of conserved subunits in plant mitochondrial import apparatus.
- Investigation of functional divergence and new roles in protein import.
Main Results:
- High conservation of essential subunits in plant mitochondrial import apparatus compared to yeast.
- Identification of expanded gene families encoding mitochondrial protein import components in plants.
- Emerging evidence of interactions between the import apparatus and respiratory chain components.
Conclusions:
- Despite conserved core components, plant mitochondrial protein import systems exhibit unique features.
- Expansions in plant mitochondrial protein import genes are essential for seed viability.
- Mitochondrial biogenesis during germination is critically dependent on inner mitochondrial protein translocases.
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Most of the mitochondrial precursors...
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Most of these mitochondrial proteins are encoded by the nucleus and imported to the mitochondria as unfolded or loosely folded precursors. Mitochondrial precursors...
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01:19Translocation of Proteins into the Mitochondria
Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
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Sorting of outer membrane proteins:
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Transport of mitochondrial precursors across the TIM23 channel is driven by...
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01:21Structure of Porins
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01:37Energy to Drive Translocation
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Generally, polypeptides are unfolded by two distinct...
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