5ZWO

Cryo-EM structure of the yeast B complex at average resolution of 3.9 angstrom

Summary for 5ZWO

• Entry DOI: 10.2210/pdb5zwo/pdb
• Related: 5ZWM 5ZWN
• EMDB information: 6972 6973 6974
• Descriptor: Pre-mRNA-splicing factor 8, U6 snRNA-associated Sm-like protein LSm2, U6 snRNA-associated Sm-like protein LSm3, ... (48 entities in total)
• Functional Keywords: spliceosome, assembly, b complex, splicing
• Biological source: Saccharomyces cerevisiae S288c (Baker's yeast); More
• Total number of polymer chains: 60
• Total formula weight: 2604025.39

Authors

Bai, R.,Wan, R.,Yan, C.,Shi, Y. (deposition date: 2018-05-16, release date: 2018-08-29, Last modification date: 2024-03-27)

Primary citation

Bai, R.,Wan, R.,Yan, C.,Lei, J.,Shi, Y.
Structures of the fully assembledSaccharomyces cerevisiaespliceosome before activation
Science, 360:1423-1429, 2018

PubMed Abstract: The precatalytic spliceosome (B complex) is preceded by the pre-B complex. Here we report the cryo-electron microscopy structures of the pre-B and B complexes at average resolutions of 3.3 to 4.6 and 3.9 angstroms, respectively. In the pre-B complex, the duplex between the 5' splice site (5'SS) and U1 small nuclear RNA (snRNA) is recognized by Yhc1, Luc7, and the Sm ring. In the B complex, U1 small nuclear ribonucleoprotein is dissociated, the 5'-exon-5'SS sequences are translocated near U6 snRNA, and three B-specific proteins may orient the precursor messenger RNA. In both complexes, U6 snRNA is anchored to loop I of U5 snRNA, and the duplex between the branch point sequence and U2 snRNA is recognized by the SF3b complex. Structural analysis reveals the mechanism of assembly and activation for the yeast spliceosome.

PubMed: 29794219
DOI: 10.1126/science.aau0325

Experimental method

ELECTRON MICROSCOPY (3.9 Å)