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Updated: Aug 15, 2026

Measurement of Protein Import Capacity of Skeletal Muscle Mitochondria
Published on: January 7, 2022
Protein translocation machineries: how organelles bring in matrix proteins
Katja Gunkel1, Marten Veenhuis, Ida J van der Klei
1Eukaryotic Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, P.O. Box 14, 9750 AA Haren, The Netherlands.
Abstract:
Eukaryotic cells contain several thousands of proteins that have to be accurately partitioned over the components of the cytoplasm (cytosol or any of the known organelles) to allow proper cell function. To this end, various specific topogenic signals have been designed as well as highly selective protein translocation machineries that ensure that each newly synthesized polypeptide reaches its correct subcellular destination or, in case of secretory proteins, is exported to the cell exterior. This contribution gives an overview regarding the principles of the main examples of polypeptide sorting and translocation, with emphasis on the function of cofactor binding in peroxisomal matrix protein import.
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