Aim24 and MICOS modulate respiratory function, tafazzin-related cardiolipin modification and mitochondrial architecture

Elife. 2014 Jan 1;3:e01684. doi: 10.7554/eLife.01684.

Abstract

Structure and function of mitochondria are intimately linked. In a search for components that participate in building the elaborate architecture of this complex organelle we have identified Aim24, an inner membrane protein. Aim24 interacts with the MICOS complex that is required for the formation of crista junctions and contact sites between inner and outer membranes. Aim24 is necessary for the integrity of the MICOS complex, for normal respiratory growth and mitochondrial ultrastructure. Modification of MICOS subunits Mic12 or Mic26 by His-tags in the absence of Aim24 leads to complete loss of cristae and respiratory complexes. In addition, the level of tafazzin, a cardiolipin transacylase, is drastically reduced and the composition of cardiolipin is modified like in mutants lacking tafazzin. In conclusion, Aim24 by interacting with the MICOS complex plays a key role in mitochondrial architecture, composition and function. DOI: http://dx.doi.org/10.7554/eLife.01684.001.

Keywords: MICOS complex; aim24; cardiolipin; contact sites; mitochondria; mitofilin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cardiolipins / metabolism*
  • Membrane Proteins / metabolism*
  • Mitochondria / metabolism*
  • Mitochondria / ultrastructure*
  • Organelle Biogenesis*
  • Oxidation-Reduction
  • Saccharomyces cerevisiae / growth & development
  • Saccharomyces cerevisiae / metabolism
  • Saccharomyces cerevisiae / physiology*
  • Saccharomyces cerevisiae Proteins / metabolism*

Substances

  • Cardiolipins
  • Membrane Proteins
  • Mic12 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins

Grant support

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.