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Oxidation-driven protein import into mitochondria: Insights and blind spots.
Jan Riemer1, Manuel Fischer, Johannes M Herrmann
1Cell Biology, University of Kaiserslautern, Erwin-Schrödinger-Straße 13, 67663 Kaiserslautern, Germany.
Biochimica Et Biophysica Acta
|June 12, 2010
Summary
Mitochondria use the Mia40-Erv1 system for oxidative protein folding, driving protein translocation across membranes. This review details the system
Area of Science:
- Mitochondrial intermembrane space biology
- Protein folding and translocation mechanisms
- Cellular redox homeostasis
Background:
- Mitochondria possess a unique system for disulfide bond introduction in proteins.
- Oxidative protein folding is hypothesized to facilitate protein translocation across the mitochondrial outer membrane.
- Key components include the oxidoreductase Mia40 and the sulfhydryl oxidase Erv1.
Purpose of the Study:
- To review current knowledge on the mitochondrial oxidative protein folding machinery.
- To elucidate the structures and mechanisms of disulfide bond formation.
- To identify and discuss outstanding questions in the field.
Main Methods:
- Review of recent literature on mitochondrial protein translocation.
- Analysis of structural data for Mia40 and Erv1.
- Mechanistic studies on disulfide bond formation and electron transfer.
Main Results:
- Mia40 recognizes substrates via a hydrophobic cleft, promoting oxidative folding.
- Erv1, a flavoenzyme, maintains Mia40 in an oxidized state and forms new disulfide bonds.
- Erv1 transfers electrons to cytochrome c and the respiratory chain.
Conclusions:
- The Mia40-Erv1 system is crucial for mitochondrial protein folding and translocation.
- Understanding the intricate mechanisms of this system is vital for cellular function.
- Further research is needed to address remaining questions regarding its regulation and dynamics.
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