The protein import machinery of mitochondria-a regulatory hub in metabolism, stress, and disease

Cell Metab. 2014 Mar 4;19(3):357-72. doi: 10.1016/j.cmet.2014.01.010. Epub 2014 Feb 20.


Mitochondria fulfill central functions in bioenergetics, metabolism, and apoptosis. They import more than 1,000 different proteins from the cytosol. It had been assumed that the protein import machinery is constitutively active and not subject to detailed regulation. However, recent studies indicate that mitochondrial protein import is regulated at multiple levels connected to cellular metabolism, signaling, stress, and pathogenesis of diseases. Here, we discuss the molecular mechanisms of import regulation and their implications for mitochondrial homeostasis. The protein import activity can function as a sensor of mitochondrial fitness and provides a direct means of regulating biogenesis, composition, and turnover of the organelle.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Energy Metabolism
  • Humans
  • Mitochondria / metabolism*
  • Mitochondrial Proteins / metabolism
  • Protein Precursors / metabolism
  • Protein Transport
  • Signal Transduction


  • Mitochondrial Proteins
  • Protein Precursors