Frataxin interacts functionally with mitochondrial electron transport chain proteins

Hum Mol Genet. 2005 Aug 1;14(15):2091-8. doi: 10.1093/hmg/ddi214. Epub 2005 Jun 16.

Abstract

Frataxin deficiency is the main cause of Friedreich ataxia, an autosomal recessive neurodegenerative disorder. Frataxin function in mitochondria has not been fully explained yet. In this work, we show that Saccharomyces cerevisiae frataxin orthologue Yfh1p interacts physically with succinate dehydrogenase complex subunits Sdh1p and Sdh2p of the yeast mitochondrial electron transport chain and also with electron transfer flavoprotein complex ETFalpha and ETFbeta subunits from the electron transfer flavoprotein complex. Genetic synthetic interaction experiments confirmed a functional relationship between YFH1 and succinate dehydrogenase genes SDH1 and SDH2. We also demonstrate a physical interaction between human frataxin and human succinate dehydrogenase complex subunits, suggesting also a key role of frataxin in the mitochondrial electron transport chain in humans. Consequently, we suggest a direct participation of the respiratory chain in the pathogenesis of the Friedreich ataxia, which we propose to be considered as an OXPHOS disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Electron Transport Chain Complex Proteins / genetics
  • Electron Transport Chain Complex Proteins / metabolism*
  • Frataxin
  • Gene Expression Regulation, Fungal
  • Humans
  • Iron-Binding Proteins / genetics
  • Iron-Binding Proteins / metabolism*
  • Mitochondria / metabolism*
  • Protein Binding / genetics
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / metabolism*
  • Succinate Dehydrogenase / genetics
  • Succinate Dehydrogenase / metabolism

Substances

  • Electron Transport Chain Complex Proteins
  • Iron-Binding Proteins
  • Succinate Dehydrogenase