Removal of an intron from a pre-mRNA by the spliceosome results in the ligation of two exons in the post-catalytic spliceosome (known as the P complex). Here, we present a cryo-EM structure of the P complex from Saccharomyces cerevisiae at an average resolution of 3.6 Å. The ligated exon is held in the active site through RNA-RNA contacts. Three bases at the 3' end of the 5' exon remain anchored to loop I of U5 small nuclear RNA, and the conserved AG nucleotides of the 3'-splice site (3'SS) are specifically recognized by the invariant adenine of the branch point sequence, the guanine base at the 5' end of the 5'SS, and an adenine base of U6 snRNA. The 3'SS is stabilized through an interaction with the 1585-loop of Prp8. The P complex structure provides a view on splice junction formation critical for understanding the complete splicing cycle.
A two-step probing method to compare lysine accessibility across macromolecular complex conformations
Termination of pre-mRNA splicing requires that the ATPase and RNA unwindase Prp43p acts on the catalytic snRNA U6
Cus2 enforces the first ATP-dependent step of splicing by binding to yeast SF3b1 through a UHM-ULM interaction
A human postcatalytic spliceosome structure reveals essential roles of metazoan factors for exon ligation
Structural dynamics of the N-terminal domain and the Switch loop of Prp8 during spliceosome assembly and activation
Genome-wide identification and functional analysis of the splicing component SYF2/NTC31/p29 across different plant species
Prp8 in a Reduced Spliceosome Lacks a Conserved Toggle that Correlates with Splicing Complexity across Diverse Taxa
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Alternative splicing a regulated gene expression process that allows a single genetic sequence to code for multiple proteins. Here is that latest research.