3IZ4

Modified E. coli tmRNA in the resume state with the tRNA-like domain in the ribosomal P site interacting with the SmpB

3IZ4 の概要

• エントリーDOI: 10.2210/pdb3iz4/pdb
• EMDBエントリー: 5234
• 分子名称: Modified E. coli transfer-messenger RNA, SsrA-binding protein (2 entities in total)
• 機能のキーワード: transfer-messenger rna, trans-translation, rna, molecular mimicry, pseudo-knots, trna-like domain, mrna-like domain, ms2, rna binding protein-rna complex, rna binding protein/rna
• 由来する生物種: Escherichia coli; 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 135742.24

構造登録者

Hashem, Y.,Fu, J.,Frank, J. (登録日: 2010-09-21, 公開日: 2010-10-20, 最終更新日: 2024-02-21)

主引用文献

Fu, J.,Hashem, Y.,Wower, I.,Lei, J.,Liao, H.Y.,Zwieb, C.,Wower, J.,Frank, J.
Visualizing the transfer-messenger RNA as the ribosome resumes translation.
Embo J., 29:3819-3825, 2010

PubMed Abstract: Bacterial ribosomes stalled by truncated mRNAs are rescued by transfer-messenger RNA (tmRNA), a dual-function molecule that contains a tRNA-like domain (TLD) and an internal open reading frame (ORF). Occupying the empty A site with its TLD, the tmRNA enters the ribosome with the help of elongation factor Tu and a protein factor called small protein B (SmpB), and switches the translation to its own ORF. In this study, using cryo-electron microscopy, we obtained the first structure of an in vivo-formed complex containing ribosome and the tmRNA at the point where the TLD is accommodated into the ribosomal P site. We show that tmRNA maintains a stable 'arc and fork' structure on the ribosome when its TLD moves to the ribosomal P site and translation resumes on its ORF. Based on the density map, we built an atomic model, which suggests that SmpB interacts with the five nucleotides immediately upstream of the resume codon, thereby determining the correct selection of the reading frame on the ORF of tmRNA.

PubMed: 20940705
DOI: 10.1038/emboj.2010.255

実験手法

ELECTRON MICROSCOPY (13.6 Å)