EMD-0441

Single-particle
4.3 Å
EMD-0441 Deposition: 13/12/2018
Map released: 19/06/2019
Last modified: 20/03/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-0441

Conformational switches control early maturation of the eukaryotic small ribosomal subunit

EMD-0441

Single-particle
4.3 Å
EMD-0441 Deposition: 13/12/2018
Map released: 19/06/2019
Last modified: 20/03/2024
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: Saccharomyces cerevisiae BY4741
Sample: 5' ETS particle
Fitted models: 6nd4 (Avg. Q-score: 0.26)

Deposition Authors: Hunziker M , Barandun J
Conformational switches control early maturation of the eukaryotic small ribosomal subunit.
PUBMED: 31206356
DOI: doi:10.7554/eLife.45185
ISSN: 2050-084X
Abstract:
Eukaryotic ribosome biogenesis is initiated with the transcription of pre-ribosomal RNA at the 5' external transcribed spacer, which directs the early association of assembly factors but is absent from the mature ribosome. The subsequent co-transcriptional association of ribosome assembly factors with pre-ribosomal RNA results in the formation of the small subunit processome. Here we show that stable rRNA domains of the small ribosomal subunit can independently recruit their own biogenesis factors in vivo. The final assembly and compaction of the small subunit processome requires the presence of the 5' external transcribed spacer RNA and all ribosomal RNA domains. Additionally, our cryo-electron microscopy structure of the earliest nucleolar pre-ribosomal assembly - the 5' external transcribed spacer ribonucleoprotein - provides a mechanism for how conformational changes in multi-protein complexes can be employed to regulate the accessibility of binding sites and therefore define the chronology of maturation events during early stages of ribosome assembly.