Movement of the decoding region of the 16 S ribosomal RNA accompanies tRNA translocation

J Mol Biol. 2000 Dec 8;304(4):507-15. doi: 10.1006/jmbi.2000.4213.

Abstract

The ribosome undergoes pronounced periodic conformational changes during protein synthesis. Of particular importance are those occurring around the decoding site, the region of the 16 S rRNA interacting with the mRNA-(tRNA)(2) complex. We have incorporated structural information from X-ray crystallography and nuclear magnetic resonance into cryo-electron microscopic maps of ribosomal complexes designed to capture structural changes at the translocation step of the polypeptide elongation cycle. The A-site region of the decoding site actively participates in the translocation of the tRNA from the A to the P-site upon GTP hydrolysis by elongation factor G, shifting approximately 8 A toward the P-site. This implies that elongation factor G actively pushes both the decoding site and the mRNA/tRNA complex during translocation.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Base Sequence
  • Binding Sites
  • Cryoelectron Microscopy
  • Crystallography, X-Ray
  • Escherichia coli / chemistry
  • Escherichia coli / genetics*
  • Guanosine Diphosphate / metabolism
  • Guanosine Triphosphate / analogs & derivatives*
  • Guanosine Triphosphate / metabolism
  • Hydrolysis
  • Models, Molecular
  • Nuclear Magnetic Resonance, Biomolecular
  • Nucleic Acid Conformation
  • Peptide Chain Elongation, Translational*
  • Peptide Elongation Factor G / metabolism
  • Protein Conformation
  • RNA, Ribosomal, 16S / chemistry*
  • RNA, Ribosomal, 16S / genetics
  • RNA, Ribosomal, 16S / metabolism*
  • RNA, Transfer / chemistry
  • RNA, Transfer / genetics
  • RNA, Transfer / metabolism*
  • Ribosomes / chemistry
  • Ribosomes / genetics
  • Ribosomes / metabolism*

Substances

  • Peptide Elongation Factor G
  • RNA, Ribosomal, 16S
  • Guanosine Diphosphate
  • 5'-guanylylmethylenebisphosphonate
  • Guanosine Triphosphate
  • RNA, Transfer