9DTR

Structure of the yeast post-catalytic P complex spliceosome at 2.3 Angstrom resolution

Summary for 9DTR

• Entry DOI: 10.2210/pdb9dtr/pdb
• EMDB information: 47157
• Descriptor: U2 snRNA, UBC4 lariat-intron, Pre-mRNA-splicing factor PRP46, ... (43 entities in total)
• Functional Keywords: spliceosome, snrna, yeast, ribonucleoprotein complex, splicing
• Biological source: Saccharomyces cerevisiae (brewer's yeast); More
• Total number of polymer chains: 47
• Total formula weight: 2280691.71

Authors

Wilkinson, M.E.,Hoskins, A.A. (deposition date: 2024-10-01, release date: 2024-12-25, Last modification date: 2025-01-01)

Primary citation

Senn, K.A.,Lipinski, K.A.,Zeps, N.J.,Griffin, A.F.,Wilkinson, M.E.,Hoskins, A.A.
Control of 3' splice site selection by the yeast splicing factor Fyv6.
Biorxiv, 2024

PubMed Abstract: Pre-mRNA splicing is catalyzed in two steps: 5' splice site (SS) cleavage and exon ligation. A number of proteins transiently associate with spliceosomes to specifically impact these steps (1 and 2 step factors). We recently identified Fyv6 (FAM192A in humans) as a 2 step factor in ; however, we did not determine how widespread Fyv6's impact is on the transcriptome. To answer this question, we have used RNA-seq to analyze changes in splicing. These results show that loss of Fyv6 results in activation of non-consensus, branch point (BP) proximal 3' SS transcriptome-wide. To identify the molecular basis of these observations, we determined a high-resolution cryo-EM structure of a yeast product complex spliceosome containing Fyv6 at 2.3 Å. The structure reveals that Fyv6 is the only 2 step factor that contacts the Prp22 ATPase and that Fyv6 binding is mutually exclusive with that of the 1 step factor Yju2. We then use this structure to dissect Fyv6 functional domains and interpret results of a genetic screen for suppressor mutations. The combined transcriptomic, structural, and genetic studies allow us to propose a model in which Yju2/Fyv6 exchange facilitates exon ligation and Fyv6 promotes usage of consensus, BP distal 3' SS.

PubMed: 38746449
DOI: 10.1101/2024.05.04.592262

Experimental method

ELECTRON MICROSCOPY (2.31 Å)