8URM

E. coli 70S ribosome with unmodified tRNAPro(GGG) bound to slippery P-site CCC-C codon and tRNAVal(UAC) in the A site

This is a non-PDB format compatible entry.

Summary for 8URM

• Entry DOI: 10.2210/pdb8urm/pdb
• EMDB information: 42495
• Descriptor: 13S ribosomal RNA, 50S ribosomal protein L5, 50S ribosomal protein L6, ... (57 entities in total)
• Functional Keywords: 70s ribosome, trna, mrna, ribosome
• Biological source: Escherichia coli; More
• Total number of polymer chains: 55
• Total formula weight: 2204378.19

Authors

Kimbrough, E.M.,Dunham, C.M.,Nguyen, H.A. (deposition date: 2023-10-26, release date: 2025-07-09, Last modification date: 2025-08-27)

Primary citation

Kimbrough, E.M.,Nguyen, H.A.,Li, H.,Mattingly, J.M.,Bailey, N.A.,Ning, W.,Gamper, H.,Hou, Y.M.,Gonzalez, R.L.,Dunham, C.M.
An RNA modification prevents extended codon-anticodon interactions from facilitating +1 frameshifting.
Nat Commun, 16:7392-7392, 2025

PubMed Abstract: RNA post-transcriptional modifications act by stabilizing the functional conformations of RNA. While their role in messenger RNA (mRNA) decoding is well established, it is less clear how transfer RNA (tRNA) modifications outside the anticodon contribute to tRNA stability and accurate protein synthesis. Absence of such modifications causes translation errors, including mRNA frameshifting. By integrating single-molecule fluorescence resonance energy transfer and cryogenic electron microscopy, we demonstrate that the N-methylguanosine (mG) modification at position 37 of Escherichia coli tRNA is necessary and sufficient for modulating the conformational energy of this tRNA on the ribosome so as to suppress +1 frameshifting otherwise induced by this tRNA. Six structures of E. coli ribosomal complexes carrying tRNA lacking mG37 show this tRNA forms four and even five codon-anticodon base pairs as it moves into the +1 frame, allowing direct visualization of the long-standing hypothesis that a four base pair codon-anticodon can form during +1 frameshifting.

PubMed: 40789848
DOI: 10.1038/s41467-025-62342-4

Experimental method

ELECTRON MICROSCOPY (3 Å)