Help Privacy Policy Disclaimer
  Advanced SearchBrowse




Journal Article

Characterization of peptides released from mitochondria: evidence for constant proteolysis and peptide efflux


Langer,  T.
Department Langer - Mitochondrial Proteostasis, Max Planck Institute for Biology of Ageing, Max Planck Society;

External Resource
Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available

Augustin, S., Nolden, M., Muller, S., Hardt, O., Arnold, I., & Langer, T. (2004). Characterization of peptides released from mitochondria: evidence for constant proteolysis and peptide efflux. J Biol Chem, 280(4), 2691-9. doi:10.1074/jbc.M410609200.

Cite as: https://hdl.handle.net/21.11116/0000-000B-7478-C
Conserved ATP-dependent proteases ensure the quality control of mitochondrial proteins and control essential steps in mitochondrial biogenesis. Recent studies demonstrated that non-assembled mitochondrially encoded proteins are degraded to peptides and amino acids that are released from mitochondria. Here, we have characterized peptides extruded from mitochondria by mass spectrometry and identified 270 peptides that are exported in an ATP- and temperature-dependent manner. The peptides originate from 51 mitochondrially and nuclearly encoded proteins localized mainly in the matrix and inner membrane, indicating that peptides generated by the activity of all known mitochondrial ATP-dependent proteases can be released from the organelle. Pulse-labeling experiments in logarithmically growing yeast cells revealed that approximately 6-12% of preexisting and newly imported proteins is degraded and contribute to this peptide pool. Under respiring conditions, we observed an increased proteolysis of newly imported proteins that suggests a higher turnover rate of respiratory chain components and thereby rationalizes the predominant appearance of representatives of this functional class in the detected peptide pool. These results demonstrated a constant efflux of peptides from mitochondria and provided new insight into the stability of the mitochondrial proteome and the efficiency of mitochondrial biogenesis.