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Updated: Jun 23, 2026

Measurement of Protein Import Capacity of Skeletal Muscle Mitochondria
Published on: January 7, 2022
Putting a break on protein translocation: metabolic regulation of mitochondrial protein import
1Cell Biology, University of Kaiserslautern, Kaiserslautern, Germany. hannes.herrmann@biologie.uni-kl.de
Abstract:
Sequence-inherent targeting information directs polypeptides synthesized in the cytosol to their respective cellular compartment. Some proteins use ambiguous sorting signals or specific folding properties to be dually distributed between the cytosol and mitochondria. A study published in this issue of Molecular Microbiology shows that in the case of fumarase this distribution is controlled by the metabolic state of yeast cells. The metabolite-dependent distribution of fumarase represents an exciting example of regulated protein import into mitochondria that shows that eukaryotes can adapt the intracellular protein distribution to their physiological conditions.
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