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Group II self-splicing introns catalyze autoexcision from precursor RNA transcripts by a mechanism strikingly similar to that of the spliceosome, an RNA-protein assembly responsible for splicing together the protein-coding parts of most eukaryotic pre-mRNAs. Splicing in both cases initiates via nucleophilic attack at the 5' splice site by the 2' OH of a conserved intron adenosine residue, creating a branched (lariat) intermediate. Here, we describe the crystal structure at 3.0 A resolution of a 70-nucleotide RNA containing the catalytically essential domains 5 and 6 of the yeast ai5gamma group II self-splicing intron, revealing an unexpected two-nucleotide bulged structure around the branch-point adenosine in domain 6.
Structural insights into group II intron catalysis and branch-site selection.,Zhang L, Doudna JA Science. 2002 Mar 15;295(5562):2084-8. Epub 2002 Feb 21. PMID:11859154[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
↑ Zhang L, Doudna JA. Structural insights into group II intron catalysis and branch-site selection. Science. 2002 Mar 15;295(5562):2084-8. Epub 2002 Feb 21. PMID:11859154 doi:10.1126/science.1069268