Architecture of the large subunit of the mammalian mitochondrial ribosome

Nature. 2014 Jan 23;505(7484):515-9. doi: 10.1038/nature12890. Epub 2013 Dec 22.


Mitochondrial ribosomes synthesize a number of highly hydrophobic proteins encoded on the genome of mitochondria, the organelles in eukaryotic cells that are responsible for energy conversion by oxidative phosphorylation. The ribosomes in mammalian mitochondria have undergone massive structural changes throughout their evolution, including ribosomal RNA shortening and acquisition of mitochondria-specific ribosomal proteins. Here we present the three-dimensional structure of the 39S large subunit of the porcine mitochondrial ribosome determined by cryo-electron microscopy at 4.9 Å resolution. The structure, combined with data from chemical crosslinking and mass spectrometry experiments, reveals the unique features of the 39S subunit at near-atomic resolution and provides detailed insight into the architecture of the polypeptide exit site. This region of the mitochondrial ribosome has been considerably remodelled compared to its bacterial counterpart, providing a specialized platform for the synthesis and membrane insertion of the highly hydrophobic protein components of the respiratory chain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cattle
  • Cryoelectron Microscopy
  • Hydrophobic and Hydrophilic Interactions
  • Mass Spectrometry
  • Mitochondria / chemistry*
  • Mitochondria / ultrastructure
  • Mitochondrial Proteins / chemistry
  • Mitochondrial Proteins / ultrastructure
  • Models, Molecular
  • Nucleic Acid Conformation
  • Protein Conformation
  • RNA, Ribosomal, 16S / chemistry
  • RNA, Ribosomal, 16S / ultrastructure
  • Ribosomal Proteins / chemistry
  • Ribosomal Proteins / ultrastructure
  • Ribosome Subunits / chemistry*
  • Ribosome Subunits / ultrastructure
  • Swine


  • Mitochondrial Proteins
  • RNA, Ribosomal, 16S
  • Ribosomal Proteins

Associated data

  • PDB/4CE4