title: Fail-safe transcriptional termination for protein-coding genes in S. cerevisiae.
abstract: Transcription termination of RNA polymerase II (Pol II) on protein-coding genes in S. cerevisiae relies on pA site recognition by 3' end processing factors. Here we demonstrate the existence of two alternative termination mechanisms that rescue polymerases failing to disengage from the template at pA sites. One of these fail-safe mechanisms is mediated by the NRD complex, similar to termination of short noncoding genes. The other termination mechanism is mediated by Rnt1 cleavage of the nascent transcript. Both fail-safe termination mechanisms trigger degradation of readthrough transcripts by the exosome. However, Rnt1-mediated termination can also enhance the usage of weak pA signals and thereby generate functional mRNA. We propose that these alternative Pol II termination pathways serve the dual function of avoiding transcription interference and promoting rapid removal of aberrant transcripts.
authors.affiliation: Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK.
authors.forename: Ana G
authors.initials: AG
authors.lastname: Rondón
authors.forename: Hannah E
authors.initials: HE
authors.lastname: Mischo
authors.forename: Junya
authors.initials: J
authors.lastname: Kawauchi
authors.forename: Nick J
authors.initials: NJ
authors.lastname: Proudfoot
mesh_terms: D024509:3' Flanking Region / Q000502:physiology; D000217:Acyltransferases / Q000235:genetics; D001665:Binding Sites / Q000235:genetics; D004247:DNA / Q000378:metabolism; D004265:DNA Helicases / Q000235:genetics; D005095:Exoribonucleases / Q000235:genetics; D009154:Mutation / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation / Q000502:physiology; D010957:Plasmids / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding / Q000502:physiology; D020365:RNA Helicases / Q000235:genetics; D012319:RNA Polymerase II / Q000378:metabolism*; D020871:RNA Stability / Q000502:physiology; D012333:RNA, Messenger / Q000096:biosynthesis* / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D043244:Ribonuclease III / Q000502:physiology*; D012441:Saccharomyces cerevisiae / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D013728:Terminator Regions, Genetic / Q000502:physiology*; D014158:Transcription, Genetic / Q000502:physiology*
chemical_list: C090564:NAB3 protein, S cerevisiae; C077734:NPL3 protein, S cerevisiae; C491211:NRD1 protein, S cerevisiae; D009687:Nuclear Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D029701:Saccharomyces cerevisiae Proteins; C075577:RAT1 protein, S cerevisiae; D004247:DNA; D000217:Acyltransferases; C081007:COOH-terminal signal transamidase; D012319:RNA Polymerase II; D005095:Exoribonucleases; C468367:RNT1 protein, S cerevisiae; D043244:Ribonuclease III; C542347:SEN1 protein, S cerevisiae; D004265:DNA Helicases; D020365:RNA Helicases