Identification of molecular interactions between P-site tRNA and the ribosome essential for translocation

Proc Natl Acad Sci U S A. 2001 Sep 25;98(20):11120-5. doi: 10.1073/pnas.211184098. Epub 2001 Sep 18.

Abstract

Translocation of the tRNA-mRNA complex is a fundamental step in the elongation cycle of protein synthesis. Our studies show that the ribosome can translocate a P-site-bound tRNA(Met) with a break in the phosphodiester backbone between positions 56 and 57 in the TPsiC-loop. We have used this fragmented P-site-bound tRNA(Met) to identify two 2'-hydroxyl groups at positions 71 and 76 in the 3'-acceptor arm that are essential for translocation. Crystallographic data show that the 2'-hydroxyl group at positions 71 and 76 contacts the backbone of 23S rRNA residues 1892 and 2433-2434, respectively, in the ribosomal E site. These results establish a set of functional interactions between P-site tRNA and 23S rRNA that are essential for translocation.

Publication types

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

MeSH terms

  • Base Sequence
  • Binding Sites
  • Escherichia coli / genetics
  • Escherichia coli / metabolism*
  • Kinetics
  • Models, Molecular
  • Molecular Sequence Data
  • Nucleic Acid Conformation
  • Oligoribonucleotides / chemical synthesis
  • Oligoribonucleotides / chemistry
  • Oligoribonucleotides / metabolism
  • Peptide Chain Elongation, Translational
  • RNA, Bacterial / chemistry
  • RNA, Bacterial / metabolism
  • RNA, Ribosomal, 23S / chemistry*
  • RNA, Ribosomal, 23S / metabolism*
  • RNA, Transfer, Met / chemistry*
  • RNA, Transfer, Met / metabolism*
  • Ribosomes / metabolism*
  • Transcription, Genetic

Substances

  • Oligoribonucleotides
  • RNA, Bacterial
  • RNA, Ribosomal, 23S
  • RNA, Transfer, Met