title: RNAse III-mediated degradation of unspliced pre-mRNAs and lariat introns.
abstract: Double-stranded RNA (dsRNA) has emerged as a modulator of gene expression, from gene silencing to antiviral responses. Here we show that dsRNA stem-loop structures found in intronic regions of the S. cerevisiae RPS22B and RPL18A transcripts trigger degradation of unspliced pre-mRNAs and lariat introns and can control the level of mRNA produced from these intron-containing genes. The dsRNA regions are cleaved by Rnt1p, the yeast ortholog of RNase III, which creates an entry site for complete degradation by the Xrn1p and Rat1p exonucleases and by the nuclear exosome. These results identify an alternative discard pathway for precursors and products of the splicing machinery and a physiological function for dsRNA in eukaryotic RNA catabolism.
authors.affiliation: Department of Chemistry and Biochemistry and The Molecular Biology Institute, University of California, Los Angeles, Box 951569, Los Angeles, CA 90095, USA.
authors.forename: Michal
authors.initials: M
authors.lastname: Danin-Kreiselman
authors.forename: Chrissie Young
authors.initials: CY
authors.lastname: Lee
authors.forename: Guillaume
authors.initials: G
authors.lastname: Chanfreau
mesh_terms: D001483:Base Sequence / Q000235:genetics; D022003:Cell Nucleus Structures / Q000235:genetics / Q000378:metabolism; D004722:Endoribonucleases / Q000235:genetics / Q000378:metabolism*; D005057:Eukaryotic Cells / Q000378:metabolism*; D005095:Exoribonucleases / Q000235:genetics / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal / Q000235:genetics; D007438:Introns / Q000235:genetics*; D012326:RNA Splicing / Q000235:genetics*; D012330:RNA, Double-Stranded / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis* / Q000235:genetics; D043244:Ribonuclease III; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic / Q000235:genetics
chemical_list: D012330:RNA, Double-Stranded; D012333:RNA, Messenger; D029701:Saccharomyces cerevisiae Proteins; C075577:RAT1 protein, S cerevisiae; D004722:Endoribonucleases; D005095:Exoribonucleases; C068398:XRN1 protein, S cerevisiae; C468367:RNT1 protein, S cerevisiae; D043244:Ribonuclease III