EMD-21858

Single-particle
3.2 Å
EMD-21858 Deposition: 23/04/2020
Map released: 24/06/2020
Last modified: 06/03/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-21858

Active 70S ribosome without free 5S rRNA and bound with A- and P- tRNA

EMD-21858

Single-particle
3.2 Å
EMD-21858 Deposition: 23/04/2020
Map released: 24/06/2020
Last modified: 06/03/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: Escherichia coli
Sample: Active 70S ribosome without free 5S rRNA and bound with A- and P- tRNA
Fitted models: 6wnw (Avg. Q-score: 0.43)

Deposition Authors: Loveland AB , Korostelev AA
Ribosome engineering reveals the importance of 5S rRNA autonomy for ribosome assembly.
PUBMED: 32518240
DOI: doi:10.1038/s41467-020-16694-8
ISSN: 2041-1723
Abstract:
5S rRNA is an indispensable component of cytoplasmic ribosomes in all species. The functions of 5S rRNA and the reasons for its evolutionary preservation as an independent molecule remain unclear. Here we used ribosome engineering to investigate whether 5S rRNA autonomy is critical for ribosome function and cell survival. By linking circularly permutated 5S rRNA with 23S rRNA we generated a bacterial strain devoid of free 5S rRNA. Viability of the engineered cells demonstrates that autonomous 5S rRNA is dispensable for cell growth under standard conditions and is unlikely to have essential functions outside the ribosome. The fully assembled ribosomes carrying 23S-5S rRNA are highly active in translation. However, the engineered cells accumulate aberrant 50S subunits unable to form stable 70S ribosomes. Cryo-EM analysis revealed a malformed peptidyl transferase center in the misassembled 50S subunits. Our results argue that the autonomy of 5S rRNA is preserved due to its role in ribosome biogenesis.