9IF7
Cryo-EM structure of the kinetoplastid trans-spliceosome activated for catalytic step II (C* complex)
This is a non-PDB format compatible entry.
Summary for 9IF7
| Entry DOI | 10.2210/pdb9if7/pdb |
| EMDB information | 52843 |
| Descriptor | Probable eukaryotic initiation factor 4A, Splicing regulator SDE2-like protein, Guanine nucleotide-binding protein subunit beta-like protein, ... (67 entities in total) |
| Functional Keywords | trans-spliceosome, spliceosome, splicing |
| Biological source | Leishmania tarentolae More |
| Total number of polymer chains | 74 |
| Total formula weight | 2816280.39 |
| Authors | Nadenoen, T.,Vanden Broeck, A. (deposition date: 2025-02-17, release date: 2026-09-02, Last modification date: 2026-10-07) |
| Primary citation | Nadenoen, T.,Biglione, F.A.,Vandevenne, M.,Vanden Broeck, A. Structural basis of step II spliced leader RNA trans-splicing in trypanosomatid parasites. Nat Commun, 17:-, 2026 Cited by PubMed Abstract: Messenger RNA (mRNA) synthesis is fundamental to eukaryotic gene expression. In kinetoplastid parasites, including the human pathogens Trypanosoma and Leishmania, mRNAs are produced through a mechanism called Spliced Leader (SL) RNA trans-splicing. In this process, a short SL exon from a small noncoding RNA is joined to the 5' end of every mRNA, ensuring transcript stability and translation. Despite decades of study, the structural and mechanistic basis of SL trans-splicing remains elusive. Here, we report cryogenic electron microscopy structures of step II SL trans-splicing machineries from Leishmania tarentolae. These structures reveal the molecular mechanism of SL exon ligation and uncover lineage-specific adaptations that remodel the trypanosomatid trans-spliceosome for SL trans-splicing while preserving fundamental spliceosomal chemistry. Altogether, our results establish a mechanistic framework for SL trans-splicing and illuminate the evolutionary diversification of RNA processing in deeply diverged eukaryotes. PubMed: 42778629DOI: 10.1038/s41467-026-77480-6 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (2.7 Å) |
Structure validation
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