Elongation factors on the ribosome

Curr Opin Struct Biol. 2005 Jun;15(3):349-54. doi: 10.1016/j.sbi.2005.05.004.


The ribosome is a complex macromolecular assembly capable of translating mRNA sequence into amino acid sequence. The adaptor molecule of translation is tRNA, but the delivery of aminoacyl-tRNAs--the primary substrate of the ribosome--relies on the formation of a ternary complex with elongation factor Tu (EF-Tu) and GTP. Likewise, elongation factor G (EF-G) is required to reset the elongation cycle through the translocation of tRNAs. Recent structures and biochemical data on ribosomes in complex with the ternary complex or EF-G have shed light on the mode of action of the elongation factors, and how this interplays with the state of tRNAs and the ribosome. A model emerges of the specific routes of conformational changes mediated by tRNA and the ribosome that trigger the GTPase activity of the elongation factors on the ribosome.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Binding Sites
  • Macromolecular Substances / chemistry
  • Macromolecular Substances / metabolism
  • Nucleic Acid Conformation
  • Peptide Elongation Factors / chemistry*
  • Peptide Elongation Factors / metabolism*
  • Peptide Elongation Factors / ultrastructure
  • Protein Binding
  • Protein Biosynthesis / physiology*
  • Protein Conformation
  • RNA, Transfer / chemistry*
  • RNA, Transfer / metabolism*
  • Ribosomes / chemistry*
  • Ribosomes / physiology*
  • Ribosomes / ultrastructure
  • Structure-Activity Relationship


  • Macromolecular Substances
  • Peptide Elongation Factors
  • RNA, Transfer