Cookies Disclaimer

OK Our site saves small pieces of text information (cookies) on your device in order to deliver better content and for statistical purposes. You can disable the usage of cookies by changing the settings of your browser. By browsing our website without changing the browser settings you grant us permission to store that information on your device.

Publication

Bibliographic Data

  • Authors: Suppanz, I.E.,Wurm, C.A.,Wenzel, D. and Jakobs, S.
  • Title: The m-AAA Protease Processes Cytochrome c Peroxidase Preferentially at the Inner Boundary Membrane of Mitochondria
  • Journal: Mol. Biol. Cell
  • Volume: 20
  • Issue: 2
  • Volume: 572-580
  • DOI: 10.1091/mbc.E07-11-1112

Abstract

The m-AAA protease is a conserved hetero-oligomeric complex in the inner membrane of mitochondria. Recent evidence suggests a compartmentalization of the contiguous mitochondrial inner membrane into an inner boundary membrane (IBM) and a cristae membrane (CM). However, little is known about the functional differences of these subdomains. We have analyzed the localizations of the m-AAA protease and its substrate cytochrome c peroxidase (Ccp1) within yeast mitochondria using live cell fluorescence microscopy and quantitative immunoelectron microscopy. We find that the m-AAA protease is preferentially localized in the IBM. Likewise, the membrane-anchored precursor form of Ccp1 accumulates in the IBM of mitochondria lacking a functional m-AAA protease. Only upon proteolytic cleavage the mature form mCcp1 moves into the cristae space. These findings suggest that protein quality control and proteolytic activation exerted by the m-AAA protease take place preferentially in the IBM pointing to significant functional differences between the IBM and the CM.