Peer-Reviewed Journal Details
Mandatory Fields
Wills, NM, O'Connor, M, Nelson, CC, Rettberg, CC, Huang, WM, Gesteland, RF, Atkins, JF;
The Embo Journal
Translational Bypassing Without Peptidyl-Trna Anticodon Scanning of Coding Gap Mrna
Optional Fields
Half the ribosomes translating the mRNA for phage T4 gene 60 topoisomerase subunit bypass a 50 nucleotide coding gap between codons 46 and 47. The pairing of codon 46 with its cognate peptidyl-tRNA anticodon dissociates, and following mRNA slippage, peptidyl-tRNA re-pairs to mRNA at a matched triplet 5' adjacent to codon 47, where translation resumes. Here, in studies with gene 60 cassettes, it is shown that the peptidyl-tRNA anticodon does not scan the intervening sequence for potential complementarity. However, certain coding gap mutants allow peptidyl-tRNA to scan sequences in the bypassed segment. A model is proposed in which the coding gap mRNA enters the ribosomal A-site and forms a structure that precludes peptidyl-tRNA scanning of its sequence. Dissipation of this RNA structure, together with the contribution of 16S rRNA anti-Shine-Dalgarno sequence pairing with GAG, facilitates peptidyl-tRNA repairing to mRNA..
DOI 10.1038/emboj.2008.170
Grant Details