title: Secondary structure is required for 3' splice site recognition in yeast.
abstract: Higher order RNA structures can mask splicing signals, loop out exons, or constitute riboswitches all of which contributes to the complexity of splicing regulation. We identified a G to A substitution between branch point (BP) and 3' splice site (3'ss) of Saccharomyces cerevisiae COF1 intron, which dramatically impaired its splicing. RNA structure prediction and in-line probing showed that this mutation disrupted a stem in the BP-3'ss region. Analyses of various COF1 intron modifications revealed that the secondary structure brought about the reduction of BP to 3'ss distance and masked potential 3'ss. We demonstrated the same structural requisite for the splicing of UBC13 intron. Moreover, RNAfold predicted stable structures for almost all distant BP introns in S. cerevisiae and for selected examples in several other Saccharomycotina species. The employment of intramolecular structure to localize 3'ss for the second splicing step suggests the existence of pre-mRNA structure-based mechanism of 3'ss recognition.
authors: Department of Cell Biology, Faculty of Science, Charles University in Prague, Prague, Czech Republic.
authors: Ondřej
authors: O
authors: Gahura
authors: Christian
authors: C
authors: Hammann
authors: Anna
authors: A
authors: Valentová
authors: František
authors: F
authors: Půta
authors: Petr
authors: P
authors: Folk
mesh_terms: D001203:Ascomycota / Q000235:genetics; D001483:Base Sequence; D051338:Cofilin 1 / Q000235:genetics; D007438:Introns; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D022821:RNA Splice Sites; D012326:RNA Splicing; D012331:RNA, Fungal / Q000737:chemistry*; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics; D013696:Temperature; D044763:Ubiquitin-Conjugating Enzymes / Q000235:genetics
chemical_list: C495813:COF1 protein, S cerevisiae; D051338:Cofilin 1; D022821:RNA Splice Sites; D012331:RNA, Fungal; D029701:Saccharomyces cerevisiae Proteins; C471610:UBC13 protein, S cerevisiae; D044763:Ubiquitin-Conjugating Enzymes