Related Experiment Video
Updated: Jul 30, 2026

Assessment of Submitochondrial Protein Localization in Budding Yeast Saccharomyces cerevisiae
Published on: July 19, 2021
Transport of proteins into mitochondria
K N Truscott1, N Pfanner, W Voos
1Institut für Biochemie und Molekularbiologie, Universität Freiburg, Hermann-Herder-Strasse 7, D-79104 Freiburg, Germany.
Abstract:
Most mitochondrial proteins are nuclear-encoded and synthesised as preproteins on polysomes in the cytosol. They must be targeted to and translocated into mitochondria. Newly synthesised preproteins interact with cytosolic factors until their recognition by receptors on the surface of mitochondria. Import into or across the outer membrane is mediated by a dynamic protein complex coined the translocase of the outer membrane (TOM). Preproteins that are imported into the matrix or inner membrane of mitochondria require the action of one of two translocation complexes of the inner membrane (TIMs). The import pathway of preproteins is predetermined by their intrinsic targeting and sorting signals. Energy input in the form of ATP and the electrical gradient across the inner membrane is required for protein translocation into mitochondria. Newly imported proteins may require molecular chaperones for their correct folding.
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