title: Kinetic competition between RNA Polymerase II and Sen1-dependent transcription termination.
abstract: The essential helicase-like protein Sen1 mediates termination of RNA Polymerase II (Pol II) transcription at snoRNAs and other noncoding RNAs in yeast. A mutation in the Pol II subunit Rpb1 that increases the elongation rate increases read-through transcription at Sen1-mediated terminators. Termination and growth defects in sen1 mutant cells are partially suppressed by a slowly transcribing Pol II mutant and are exacerbated by a faster-transcribing Pol II mutant. Deletion of the nuclear exosome subunit Rrp6 allows visualization of noncoding RNA intermediates that are terminated but not yet processed. Sen1 mutants or faster-transcribing Pol II increase the average lengths of preprocessed snoRNA, CUT, and SUT transcripts, while slowed Pol II transcription produces shorter transcripts. These connections between transcription rate and Sen1 activity support a model whereby kinetic competition between elongating Pol II and Sen1 helicase establishes the temporal and spatial window for early Pol II termination.
authors.affiliation: Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
authors.forename: Dane Z
authors.initials: DZ
authors.lastname: Hazelbaker
authors.forename: Sebastian
authors.initials: S
authors.lastname: Marquardt
authors.forename: Wiebke
authors.initials: W
authors.lastname: Wlotzka
authors.forename: Stephen
authors.initials: S
authors.lastname: Buratowski
mesh_terms: D000483:Alleles; D020816:Amino Acid Motifs; D019943:Amino Acid Substitution; D002874:Chromosome Mapping; D004265:DNA Helicases / Q000235:genetics / Q000378:metabolism*; D007700:Kinetics; D020365:RNA Helicases / Q000235:genetics / Q000378:metabolism*; D012319:RNA Polymerase II / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D012331:RNA, Fungal / Q000235:genetics / Q000378:metabolism; D020537:RNA, Small Nucleolar / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D061806:Transcription Termination, Genetic
chemical_list: D012331:RNA, Fungal; D020537:RNA, Small Nucleolar; D029701:Saccharomyces cerevisiae Proteins; D012319:RNA Polymerase II; C511736:RPB1 protein, S cerevisiae; C542347:SEN1 protein, S cerevisiae; D004265:DNA Helicases; D020365:RNA Helicases