Fiche publication
Date publication
janvier 2016
Journal
Nature communications
Auteurs
Membres identifiés du Cancéropôle Est :
Dr YUSUPOV Marat
,
Dr YUSUPOVA Gulnara
Tous les auteurs :
Rozov A, Demeshkina N, Khusainov I, Westhof E, Yusupov M, Yusupova G
Lien Pubmed
Résumé
Posttranscriptional modifications at the wobble position of transfer RNAs play a substantial role in deciphering the degenerate genetic code on the ribosome. The number and variety of modifications suggest different mechanisms of action during messenger RNA decoding, of which only a few were described so far. Here, on the basis of several 70S ribosome complex X-ray structures, we demonstrate how Escherichia coli tRNA(Lys)(UUU) with hypermodified 5-methylaminomethyl-2-thiouridine (mnm(5)s(2)U) at the wobble position discriminates between cognate codons AAA and AAG, and near-cognate stop codon UAA or isoleucine codon AUA, with which it forms pyrimidine-pyrimidine mismatches. We show that mnm(5)s(2)U forms an unusual pair with guanosine at the wobble position that expands general knowledge on the degeneracy of the genetic code and specifies a powerful role of tRNA modifications in translation. Our models consolidate the translational fidelity mechanism proposed previously where the steric complementarity and shape acceptance dominate the decoding mechanism.
Mots clés
Base Pairing, Base Sequence, Codon, chemistry, Escherichia coli, chemistry, Genetic Code, Nucleic Acid Conformation, Protein Biosynthesis, RNA, Messenger, chemistry, RNA, Transfer, chemistry, Ribosomes, genetics, Thiouridine, analogs & derivatives
Référence
Nat Commun. 2016 Jan 21;7:10457
