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Updated: Jul 8, 2026

Reconstitution of Msp1 Extraction Activity with Fully Purified Components
Published on: August 10, 2021
Multiple pathways for sorting mitochondrial precursor proteins
Natalia Bolender1, Albert Sickmann, Richard Wagner
1Institut für Biochemie und Molekularbiologie, Zentrum für Biochemie und Molekulare Zellforschung, Universität Freiburg, Germany.
Abstract:
Mitochondria import hundreds of different precursor proteins from the cytosol. More than 50% of mitochondrial proteins do not use the classical import pathway that is guided by amino-terminal presequences, but instead contain different types of internal targeting signals. Recent studies have revealed an unexpected complexity of the mitochondrial protein import machinery and have led to the discovery of new transport pathways. Here, we review the versatility of mitochondrial protein import and its connection to mitochondrial morphology, redox regulation and energetics.
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