Experientia

, Volume 52, Issue 12, pp 1069–1076

Regulated protein degradation in mitochondria

Milti-Author Reviews

DOI: 10.1007/BF01952104

Cite this article as:
Langer, T. & Neupert, W. Experientia (1996) 52: 1069. doi:10.1007/BF01952104

Abstract

Various adenosine triphosphate (ATP)-dependent proteases were identified within mitochondria which mediate selective mitochondrial protein degradation and fulfill crucial functions in mitochondrial biogenesis. The matrix-localized PIM1 protease, a homologue of theEscherichia coli Lon protease, is required for respiration and maintenance of mitochondrial genome integrity. Degradation of non-native polypeptides by PIM1 protease depends on the chaperone activity of the mitochondrial Hsp70 system, posing intriguing questions about the relation between the proteolytic system and the folding machinery in mitochondria. The mitochondrial inner membrane harbors two ATP-dependent metallopeptidases, them- and thei-AAA protease, which expose their catalytic sites to opposite membrane surfaces and cooperate in the degradation of inner membrane proteins. In addition to its proteolytic activity, them-AAA protease has chaperone-like activity during the assembly of respiratory and ATP-synthase complexes. It constitutes a quality control system in the inner membrane for membrane-embedded protein complexes.

Key words

MitochondriaproteolysisPIM1 proteaseAAA proteasechaperone

Copyright information

© Birkhäuser Verlag 1996

Authors and Affiliations

  1. 1.Institut für Physiologische Chemie der Universität MünchenMünchen(Germany)