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Updated: Apr 17, 2026

Assessment of Submitochondrial Protein Localization in Budding Yeast Saccharomyces cerevisiae
Published on: July 19, 2021
Import of proteins into isolated yeast mitochondria
Valentina Peleh1, Ajay Ramesh, Johannes M Herrmann
1Cell Biology, University of Kaiserslautern, Erwin-Schrodinger-Strasse 13, 67663, Kaiserslautern, Germany.
Abstract:
Mitochondria are essential organelles of eukaryotic cells. The vast majority of mitochondrial proteins is encoded within the nuclear genome and translocated into various mitochondrial compartments after translation in the cytosol as preproteins. Even in rather primitive eukaryotes like yeasts, there are 700-1,000 different proteins that need to be recognized in the cytosol, directed to the protein translocases in the two mitochondrial membranes and sorted to their appropriate mitochondrial subcompartment. In vitro reconstituted import systems have proved to be important tools to study these processes in detail. Using isolated mitochondria and radioactively labeled precursor proteins, it was possible to identify several import machineries and pathways consisting of a large number of components during the last few decades.
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