title: The transcription elongation factor TFIIS is a component of RNA polymerase II preinitiation complexes.
abstract: In this article, we provide direct evidence that the evolutionarily conserved transcription elongation factor TFIIS functions during preinitiation complex assembly. First, we identified TFIIS in a mass spectrometric screen of RNA polymerase II (Pol II) preinitiation complexes (PICs). Second, we show that the association of TFIIS with a promoter depends on functional PIC components including Mediator and the SAGA complex. Third, we demonstrate that TFIIS is required for efficient formation of active PICs. Using truncation mutants of TFIIS, we find that the Pol II-binding domain is the minimal domain necessary to stimulate PIC assembly. However, efficient formation of active PICs requires both the Pol II-binding domain and the poorly understood N-terminal domain. Importantly, Domain III, which is required for the elongation function of TFIIS, is dispensable during PIC assembly. The results demonstrate that TFIIS is a PIC component that is required for efficient formation and/or stability of the complex.
authors.affiliation: Institute for Systems Biology, 1441 North 34th Street, Seattle, WA 98103, USA.
authors.forename: Bong
authors.initials: B
authors.lastname: Kim
authors.forename: Alexey I
authors.initials: AI
authors.lastname: Nesvizhskii
authors.forename: P Geetha
authors.initials: PG
authors.lastname: Rani
authors.forename: Steven
authors.initials: S
authors.lastname: Hahn
authors.forename: Ruedi
authors.initials: R
authors.lastname: Aebersold
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Ranish
mesh_terms: D001665:Binding Sites / Q000235:genetics; D004271:DNA, Fungal / Q000235:genetics / Q000378:metabolism; D046912:Multiprotein Complexes; D011401:Promoter Regions, Genetic; D017434:Protein Structure, Tertiary; D012319:RNA Polymerase II / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D017384:Sequence Deletion; D053719:Tandem Mass Spectrometry; D014158:Transcription, Genetic; D035602:Transcriptional Elongation Factors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*
chemical_list: D004271:DNA, Fungal; D046912:Multiprotein Complexes; D029701:Saccharomyces cerevisiae Proteins; D035602:Transcriptional Elongation Factors; C018648:transcription factor S-II; D012319:RNA Polymerase II