5NRL

Structure of a pre-catalytic spliceosome

This is a non-PDB format compatible entry.

Summary for 5NRL

• Entry DOI: 10.2210/pdb5nrl/pdb
• EMDB information: 3682 3683 3684 3685 3686 3687 3688
• Descriptor: U2 snRNA, Pre-mRNA-splicing factor SNU114, Spliceosomal protein DIB1, ... (46 entities in total)
• Functional Keywords: spliceosome, splicing, ribonucleoprotein
• Biological source: Saccharomyces cerevisiae; More
• Total number of polymer chains: 58
• Total formula weight: 2551708.64

Authors

Plaschka, C.,Lin, P.-C.,Nagai, K. (deposition date: 2017-04-24, release date: 2017-05-31, Last modification date: 2024-11-20)

Primary citation

Plaschka, C.,Lin, P.C.,Nagai, K.
Structure of a pre-catalytic spliceosome.
Nature, 546:617-621, 2017

PubMed Abstract: Intron removal requires assembly of the spliceosome on precursor mRNA (pre-mRNA) and extensive remodelling to form the spliceosome's catalytic centre. Here we report the cryo-electron microscopy structure of the yeast Saccharomyces cerevisiae pre-catalytic B complex spliceosome at near-atomic resolution. The mobile U2 small nuclear ribonucleoprotein particle (snRNP) associates with U4/U6.U5 tri-snRNP through the U2/U6 helix II and an interface between U4/U6 di-snRNP and the U2 snRNP SF3b-containing domain, which also transiently contacts the helicase Brr2. The 3' region of the U2 snRNP is flexibly attached to the SF3b-containing domain and protrudes over the concave surface of tri-snRNP, where the U1 snRNP may reside before its release from the pre-mRNA 5' splice site. The U6 ACAGAGA sequence forms a hairpin that weakly tethers the 5' splice site. The B complex proteins Prp38, Snu23 and Spp381 bind the Prp8 N-terminal domain and stabilize U6 ACAGAGA stem-pre-mRNA and Brr2-U4 small nuclear RNA interactions. These results provide important insights into the events leading to active site formation.

PubMed: 28530653
DOI: 10.1038/nature22799

Experimental method

ELECTRON MICROSCOPY (7.2 Å)