title: Holo-TFIID supports transcriptional stimulation by diverse activators and from a TATA-less promoter.
abstract: Transcription factor IID (TFIID) binds to TATA boxes, nucleating the assembly of initiation complexes containing several general transcription factors and RNA polymerase II. Recently, TFIID was shown to be a multisubunit complex containing a TATA box-binding polypeptide (TBP) and several tightly associated polypeptides (TAFs), which are required for transcriptional stimulation by activator proteins. Here, we report the development of a human cell line expressing an epitope-tagged TBP and the immunopurification of a native, high-molecular-weight form of TFIID that supports transcriptional stimulation by several different classes of activation domains. Recovery of basal and activated TFIID transcriptional specific activity was close to approximately 100%. Electrophoretic mobility-shift analysis demonstrated a single major DNA-protein complex. This holo-TFIID contains TAFs of approximately 250, 125, 95, 78, and 50 kD and sediments at 17S. Holo-TFIID produced an extended footprint over the adenovirus major late promoter TATA box and initiator sequence and supported transcriptional activation from a promoter lacking a TATA box. These results lead us to hypothesize that a single multisubunit TFIID protein supports transcriptional stimulation by diverse activation domains and from a TATA-less promoter.
authors.affiliation: Department of Microbiology and Molecular Genetics, University of California, Los Angeles 90024-1570.
authors.forename: Q
authors.initials: Q
authors.lastname: Zhou
authors.forename: P M
authors.initials: PM
authors.lastname: Lieberman
authors.forename: T G
authors.initials: TG
authors.lastname: Boyer
authors.forename: A J
authors.initials: AJ
authors.lastname: Berk
mesh_terms: D001483:Base Sequence; D015153:Blotting, Western; D002460:Cell Line; D016172:DNA Fingerprinting; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D010957:Plasmids; D011401:Promoter Regions, Genetic; D012319:RNA Polymerase II / Q000378:metabolism; D016385:TATA Box; D035181:TATA-Box Binding Protein; D035362:Transcription Factor TFIID; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D014764:Viral Proteins
chemical_list: D004268:DNA-Binding Proteins; C051096:MLTF protein, adenovirus; D009838:Oligodeoxyribonucleotides; D035181:TATA-Box Binding Protein; D035362:Transcription Factor TFIID; D014157:Transcription Factors; D014764:Viral Proteins; D012319:RNA Polymerase II