6bk8

S. cerevisiae spliceosomal post-catalytic P complexS. cerevisiae spliceosomal post-catalytic P complex

6bk8, resolution 3.30Å Show:Asymmetric Unit Biological Assembly Structural highlights 6bk8 is a 13 chain structure with sequence from Saccharomyces cerevisiae S288C. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: Electron Microscopy, Resolution 3.3Å Ligands: Experimental data: Check Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function SLT11_YEAST Involved in pre-mRNA splicing. Facilitates the cooperative formation of U2/U6 helix II in association with stem II in the spliceosome. Binds to RNA. Publication Abstract from PubMed The spliceosome undergoes dramatic changes in a splicing cycle. Structures of B, B(act), 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. Structure of the yeast spliceosomal postcatalytic P complex.,Liu S, Li X, Zhang L, Jiang J, Hill RC, Cui Y, Hansen KC, Zhou ZH, Zhao R Science. 2017 Dec 8;358(6368):1278-1283. doi: 10.1126/science.aar3462. Epub 2017 , Nov 16. PMID:29146870 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Nucleoprotein 3D structures Pre-mRNA splicing factors 3D structures Sm-like protein 3D structures