Ribosomal 18S rRNA base pairs with mRNA during eukaryotic translation initiation.
Fiche publication
Date publication
août 2016
Journal
Nature communications
Auteurs
Membres identifiés du Cancéropôle Est :
Dr KLAHOLZ Bruno, Dr SIMONETTI Angelita
Tous les auteurs :
Martin F, Ménétret JF, Simonetti A, Myasnikov AG, Vicens Q, Prongidi-Fix L, Natchiar SK, Klaholz BP, Eriani G
Lien Pubmed
Résumé
Eukaryotic mRNAs often contain a Kozak sequence that helps tether the ribosome to the AUG start codon. The mRNA of histone H4 (h4) does not undergo classical ribosome scanning but has evolved a specific tethering mechanism. The cryo-EM structure of the rabbit ribosome complex with mouse h4 shows that the mRNA forms a folded, repressive structure at the mRNA entry site on the 40S subunit next to the tip of helix 16 of 18S ribosomal RNA (rRNA). Toe-printing and mutational assays reveal that an interaction exists between a purine-rich sequence in h4 mRNA and a complementary UUUC sequence of helix h16. Together the present data establish that the h4 mRNA harbours a sequence complementary to an 18S rRNA sequence which tethers the mRNA to the ribosome to promote proper start codon positioning, complementing the interactions of the 40S subunit with the Kozak sequence that flanks the AUG start codon.
Mots clés
Animals, Base Pairing, Base Sequence, Codon, Initiator, Histones, biosynthesis, Mice, Models, Molecular, Mutation, Nucleic Acid Conformation, Peptide Chain Initiation, Translational, genetics, RNA, Messenger, chemistry, RNA, Ribosomal, 18S, chemistry, Rabbits, Ribosomes, chemistry
Référence
Nat Commun. 2016 08 24;7:12622