Dual Role of Mitofilin in Mitochondrial Membrane Organization and Protein Biogenesis

Dev Cell. 2011 Oct 18;21(4):694-707. doi: 10.1016/j.devcel.2011.08.026. Epub 2011 Sep 22.

Abstract

The mitochondrial inner membrane consists of two domains, inner boundary membrane and cristae membrane that are connected by crista junctions. Mitofilin/Fcj1 was reported to be involved in formation of crista junctions, however, different views exist on its function and possible partner proteins. We report that mitofilin plays a dual role. Mitofilin is part of a large inner membrane complex, and we identify five partner proteins as constituents of the mitochondrial inner membrane organizing system (MINOS) that is required for keeping cristae membranes connected to the inner boundary membrane. Additionally, mitofilin is coupled to the outer membrane and promotes protein import via the mitochondrial intermembrane space assembly pathway. Our findings indicate that mitofilin is a central component of MINOS and functions as a multifunctional regulator of mitochondrial architecture and protein biogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chromatography, Affinity
  • Humans
  • Intracellular Membranes / metabolism*
  • Mitochondria / metabolism*
  • Mitochondrial Membrane Transport Proteins / metabolism*
  • Mitochondrial Membranes / metabolism*
  • Mitochondrial Proteins / metabolism*
  • Protein Binding
  • Protein Biosynthesis*
  • Protein Transport
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / growth & development
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  • Transposases / metabolism

Substances

  • Mitochondrial Membrane Transport Proteins
  • Mitochondrial Proteins
  • Saccharomyces cerevisiae Proteins
  • Minos transposase
  • Transposases