Transport of Proteins into Mitochondria

  • Katja G. Hansen
  • Johannes M. HerrmannEmail author


Mitochondria are essential organelles of eukaryotic cells. They consist of hundreds of different proteins that exhibit crucial activities in respiration, catabolic metabolism and the synthesis of amino acids, lipids, heme and iron-sulfur clusters. With the exception of a handful of hydrophobic mitochondrially encoded membrane proteins, all these proteins are synthesized on cytosolic ribosomes, targeted to receptors on the mitochondrial surface, and transported across or inserted into the outer and inner mitochondrial membrane before they are folded and assembled into their final native structure. This review article provides a comprehensive overview of the mechanisms and components of the mitochondrial protein import systems with a particular focus on recent developments in the field.


ER-SURF Mitochondria Protein import Targeting signals 



We thank Janina Laborenz and Clara Stiefel for critical reading of the manuscript. This work was funded by grants of the Deutsche Forschungsgemeinschaft (He2803/4-2, SPP1710 and IRTG1830 and DIP Mitobalance).

Compliance with Ethical Standards

Conflict of interest

The authors KGH and JMH declare that they have no conflict of interest.

Research Involving Human Participants and/or Animals

This article does not contain any studies with human participants or animals performed by any of the authors.


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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Cell BiologyUniversity of KaiserslauternKaiserslauternGermany

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