EMD-35673

Single-particle
3.5 Å
EMD-35673 Deposition: 17/03/2023
Map released: 09/08/2023
Last modified: 15/11/2023
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links

EMD-35673

human nuclear pre-60S ribosomal particle - State B'

EMD-35673

Single-particle
3.5 Å
EMD-35673 Deposition: 17/03/2023
Map released: 09/08/2023
Last modified: 15/11/2023
Overview 3D View Sample Experiment Validation Volume Browser Additional data Links
Sample Organism: Homo sapiens
Sample: cryo-EM structure of human nuclear pre-60S ribosomal particle - State B
Fitted models: 8ir3 (Avg. Q-score: 0.439)

Deposition Authors: Zhang Y, Gao N
Visualizing the nucleoplasmic maturation of human pre-60S ribosomal particles.
Zhang Y, Liang X, Luo S, Chen Y, Li Y , Ma C, Li N , Gao N
(2023) Cell Res , 33 , 867 - 878
PUBMED: 37491604
DOI: doi:10.1038/s41422-023-00853-9
ISSN: 1001-0602
Abstract:
Eukaryotic ribosome assembly is a highly orchestrated process that involves over two hundred protein factors. After early assembly events on nascent rRNA in the nucleolus, pre-60S particles undergo continuous maturation steps in the nucleoplasm, and prepare for nuclear export. Here, we report eleven cryo-EM structures of the nuclear pre-60S particles isolated from human cells through epitope-tagged GNL2, at resolutions of 2.8-4.3 Å. These high-resolution snapshots provide fine details for several major structural remodeling events at a virtual temporal resolution. Two new human nuclear factors, L10K and C11orf98, were also identified. Comparative structural analyses reveal that many assembly factors act as successive place holders to control the timing of factor association/dissociation events. They display multi-phasic binding properties for different domains and generate complex binding inter-dependencies as a means to guide the rRNA maturation process towards its mature conformation. Overall, our data reveal that nuclear assembly of human pre-60S particles is generally hierarchical with short branch pathways, and a few factors display specific roles as rRNA chaperones by confining rRNA helices locally to facilitate their folding, such as the C-terminal domain of SDAD1.