Ribosome. The complete structure of the 55S mammalian mitochondrial ribosome

Science. 2015 Apr 17;348(6232):303-8. doi: 10.1126/science.aaa3872. Epub 2015 Apr 2.


Mammalian mitochondrial ribosomes (mitoribosomes) synthesize mitochondrially encoded membrane proteins that are critical for mitochondrial function. Here we present the complete atomic structure of the porcine 55S mitoribosome at 3.8 angstrom resolution by cryo-electron microscopy and chemical cross-linking/mass spectrometry. The structure of the 28S subunit in the complex was resolved at 3.6 angstrom resolution by focused alignment, which allowed building of a detailed atomic structure including all of its 15 mitoribosomal-specific proteins. The structure reveals the intersubunit contacts in the 55S mitoribosome, the molecular architecture of the mitoribosomal messenger RNA (mRNA) binding channel and its interaction with transfer RNAs, and provides insight into the highly specialized mechanism of mRNA recruitment to the 28S subunit. Furthermore, the structure contributes to a mechanistic understanding of aminoglycoside ototoxicity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aminoglycosides / chemistry
  • Animals
  • Anti-Bacterial Agents / chemistry
  • Binding Sites
  • GTP-Binding Proteins / chemistry
  • Humans
  • Mitochondria / ultrastructure*
  • Mitochondrial Membranes / ultrastructure
  • Mitochondrial Proteins / biosynthesis*
  • Mitochondrial Proteins / genetics
  • Mutation
  • Nucleic Acid Conformation
  • Protein Structure, Secondary
  • RNA, Messenger / chemistry
  • RNA, Ribosomal, 16S / chemistry
  • RNA, Transfer / chemistry
  • Ribosomal Proteins / chemistry
  • Ribosome Subunits, Large / chemistry
  • Ribosome Subunits, Large / physiology
  • Ribosome Subunits, Large / ultrastructure*
  • Swine


  • Aminoglycosides
  • Anti-Bacterial Agents
  • Mitochondrial Proteins
  • RNA, Messenger
  • RNA, Ribosomal, 16S
  • Ribosomal Proteins
  • RNA, Transfer
  • GTP-Binding Proteins

Associated data

  • PDB/5AJ3
  • PDB/5AJ4