5WYJ

Cryo-EM structure of the 90S small subunit pre-ribosome (Dhr1-depleted, Enp1-TAP, state 1)

This is a non-PDB format compatible entry.

Summary for 5WYJ

• Entry DOI: 10.2210/pdb5wyj/pdb
• EMDB information: 6695
• Descriptor: U3 RNA, Utp8, Utp9, ... (61 entities in total)
• Functional Keywords: ribosome, 90s, pre-ribosome, protein-rna complex
• Biological source: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast); More
• Total number of polymer chains: 64
• Total formula weight: 4111922.21

Authors

Ye, K.,Zhu, X.,Sun, Q. (deposition date: 2017-01-13, release date: 2017-03-29, Last modification date: 2025-09-17)

Primary citation

Sun, Q.,Zhu, X.,Qi, J.,An, W.,Lan, P.,Tan, D.,Chen, R.,Wang, B.,Zheng, S.,Zhang, C.,Chen, X.,Zhang, W.,Chen, J.,Dong, M.Q.,Ye, K.
Molecular architecture of the 90S small subunit pre-ribosome.
Elife, 6:-, 2017

PubMed Abstract: Eukaryotic small ribosomal subunits are first assembled into 90S pre-ribosomes. The complete 90S is a gigantic complex with a molecular mass of approximately five megadaltons. Here, we report the nearly complete architecture of 90S determined from three cryo-electron microscopy single particle reconstructions at 4.5 to 8.7 angstrom resolution. The majority of the density maps were modeled and assigned to specific RNA and protein components. The nascent ribosome is assembled into isolated native-like substructures that are stabilized by abundant assembly factors. The 5' external transcribed spacer and U3 snoRNA nucleate a large subcomplex that scaffolds the nascent ribosome. U3 binds four sites of pre-rRNA, including a novel site on helix 27 but not the 3' side of the central pseudoknot, and crucially organizes the 90S structure. The 90S model provides significant insight into the principle of small subunit assembly and the function of assembly factors.

PubMed: 28244370
DOI: 10.7554/eLife.22086

Experimental method

ELECTRON MICROSCOPY (8.7 Å)