Differential protein distributions define two sub-compartments of the mitochondrial inner membrane in yeast

FEBS Lett. 2006 Oct 16;580(24):5628-34. doi: 10.1016/j.febslet.2006.09.012. Epub 2006 Sep 18.

Abstract

The mitochondrial inner membrane exhibits a complex topology. Its infolds, the cristae membranes, are contiguous with the inner boundary membrane (IBM), which runs parallel to the outer membrane. Using live cells co-expressing functional fluorescent fusion proteins, we report on the distribution of inner membrane proteins in budding yeast. To this end we introduce the enlarged mitochondria of Deltamdm10, Deltamdm31, Deltamdm32, and Deltammm1 cells as a versatile model system to study sub-mitochondrial protein localizations. Proteins of the F(1)F(0) ATP synthase and of the respiratory chain complexes III and IV were visualized in the cristae-containing interior of the mitochondria. In contrast, proteins of the TIM23 complex and of the presequence translocase-associated motor were strongly enriched at the IBM. The different protein distributions shown here demonstrate that the cristae membranes and the IBM are functionally distinct sub-compartments.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Gene Expression Regulation, Fungal*
  • Genes, Reporter / genetics
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism
  • Mitochondrial Membranes / metabolism*
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Saccharomyces cerevisiae Proteins / genetics
  • Saccharomyces cerevisiae Proteins / metabolism*

Substances

  • Membrane Proteins
  • Recombinant Fusion Proteins
  • Saccharomyces cerevisiae Proteins