6BK8

S. cerevisiae spliceosomal post-catalytic P complex

Summary for 6BK8

• Entry DOI: 10.2210/pdb6bk8/pdb
• EMDB information: 7109
• Descriptor: U2 snRNA, Pre-mRNA-splicing factor SLT11, Pre-mRNA-splicing factor CWC2, ... (40 entities in total)
• Functional Keywords: pre-mrna splicing, spliceosome, post-catalytic, p complex, rna binding protein
• Biological source: Saccharomyces cerevisiae; More
• Total number of polymer chains: 46
• Total formula weight: 2221623.50

Authors

Liu, S.,Li, X.,Zhou, Z.H.,Zhao, R. (deposition date: 2017-11-07, release date: 2018-02-21, Last modification date: 2024-11-20)

Primary citation

Liu, S.,Li, X.,Zhang, L.,Jiang, J.,Hill, R.C.,Cui, Y.,Hansen, K.C.,Zhou, Z.H.,Zhao, R.
Structure of the yeast spliceosomal postcatalytic P complex.
Science, 358:1278-1283, 2017

PubMed Abstract: The spliceosome undergoes dramatic changes in a splicing cycle. Structures of B, B, C, C*, and intron lariat spliceosome complexes revealed mechanisms of 5'-splice site (ss) recognition, branching, and intron release, but lacked information on 3'-ss recognition, exon ligation, and exon release. Here we report a cryo-electron microscopy structure of the postcatalytic P complex at 3.3-angstrom resolution, revealing that the 3' ss is mainly recognized through non-Watson-Crick base pairing with the 5' ss and branch point. Furthermore, one or more unidentified proteins become stably associated with the P complex, securing the 3' exon and potentially regulating activity of the helicase Prp22. Prp22 binds nucleotides 15 to 21 in the 3' exon, enabling it to pull the intron-exon or ligated exons in a 3' to 5' direction to achieve 3'-ss proofreading or exon release, respectively.

PubMed: 29146870
DOI: 10.1126/science.aar3462

Experimental method

ELECTRON MICROSCOPY (3.3 Å)