5d8b
From Proteopedia
Crystal structure of T. thermophilus ribosome containing a P-site wobble mismatch
Structural highlights
FunctionRL2_THET8 One of the primary rRNA binding proteins. Required for association of the 30S and 50S subunits to form the 70S ribosome, for tRNA binding and peptide bond formation. It has been suggested to have peptidyltransferase activity; this is somewhat controversial (By similarity). Makes several contacts with the 16S rRNA (forming bridge B7b) in the 70S ribosome.[HAMAP-Rule:MF_01320_B] Publication Abstract from PubMedTranslation initiation in the P site occasionally occurs at atypical (non-AUG) start codons, including those forming a mismatch in the third (wobble) position. During elongation, however, a pyrimidine-pyrimidine wobble mismatch may trigger a translation quality-control mechanism, whereby the P-site mismatch is thought to perturb the downstream A-site codon or the decoding center, thereby reducing translation fidelity and inducing termination of aberrant translation. We report a crystal structure of the 70S initiation complex containing an AUC codon in the ribosomal P site. Remarkably, the ribosome stabilizes the mismatched codon-anticodon helix, arranging a normally disruptive cytosine-cytosine pair into a Watson-Crick-like conformation. Translation-competent conformations of the tRNA, mRNA, and decoding center suggest that a P-site wobble-position mismatch in the 70S initiation complex does not pre-arrange the mRNA or decoding center to favor subsequent miscoding events. Ribosome Structure Reveals Preservation of Active Sites in the Presence of a P-Site Wobble Mismatch.,Svidritskiy E, Korostelev AA Structure. 2015 Sep 15. pii: S0969-2126(15)00361-5. doi:, 10.1016/j.str.2015.08.011. PMID:26412335[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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