5WYK

Cryo-EM structure of the 90S small subunit pre-ribosome (Mtr4-depleted, Enp1-TAP)

This is a non-PDB format compatible entry.

Summary for 5WYK

• Entry DOI: 10.2210/pdb5wyk/pdb
• Related: 5WYJ
• EMDB information: 6695 6696 6697
• Descriptor: U3 RNA, Utp8, Utp9, ... (55 entities in total)
• Functional Keywords: ribosome, 90s, pre-ribosome, protein-rna complex
• Biological source: Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast); More
• Cellular location: Nucleus, nucleolus: P42945 P25635 Q12220 Q05946 P40362 P15646 Q06078 P25368 P53254 Q06287 P25586 P32899 P53941 P47083 Q12460 Q08096 Q12499 Q06506 Q05498 P36144 P39990; Cytoplasm : Q08965 Q99216 P33442 P0CX35 P26783 P26786 P0CX39 O13516 P0CX47 P05756 P06367 P0CX51 P0C0W1 P0CX29 P0CX31 P35997 Q3E7X9 P0CX33
• Total number of polymer chains: 58
• Total formula weight: 3618023.80

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 (4.5 Å)