Preparing your results

Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.

A heme-sensing mechanism in the translational regulation of mitochondrial cytochrome c oxidase biogenesis.

Heme plays fundamental roles as cofactor and signaling molecule in multiple pathways devoted to oxygen sensing and utilization in aerobic organisms. For cellular respiration, heme serves as a prosthetic group in electron transfer proteins and redox enzymes. Here we report that in the yeast Saccharomyces cerevisiae, a heme-sensing mechanism translationally controls the biogenesis of cytochrome c oxidase (COX), the terminal mitochondrial respiratory chain enzyme. We show that Mss51, a COX1 mRNA-specific translational activator and Cox1 chaperone, which coordinates Cox1 synthesis in mitoribosomes with its assembly in COX, is a heme-binding protein. Mss51 contains two heme regulatory motifs or Cys-Pro-X domains located in its N terminus. Using a combination of in vitro and in vivo approaches, we have demonstrated that these motifs are important for heme binding and efficient performance of Mss51 functions. We conclude that heme sensing by Mss51 regulates COX biogenesis and aerobic energy production.

Pubmed ID: 23217259


  • Soto IC
  • Fontanesi F
  • Myers RS
  • Hamel P
  • Barrientos A


Cell metabolism

Publication Data

December 5, 2012

Associated Grants

  • Agency: NIGMS NIH HHS, Id: F31 GM081975
  • Agency: NIGMS NIH HHS, Id: GM081975
  • Agency: NIAID NIH HHS, Id: P30 AI 073961
  • Agency: NIGMS NIH HHS, Id: R01 GM071775
  • Agency: NIGMS NIH HHS, Id: R01 GM071775-06

Mesh Terms

  • Amino Acid Motifs
  • Amino Acid Sequence
  • Electron Transport Complex IV
  • Heme
  • Kinetics
  • Mitochondria
  • Mitochondrial Turnover
  • Molecular Sequence Data
  • Mutation
  • Protein Binding
  • Protein Processing, Post-Translational
  • Recombinant Proteins
  • Saccharomyces cerevisiae
  • Saccharomyces cerevisiae Proteins
  • Sequence Alignment
  • Transcription Factors