title: Dimerization of TFIID when not bound to DNA.
abstract: For unknown reasons, the eukaryotic transcription factor TFIID inefficiently recognizes promoters. Human TFIID was found to form highly specific homodimers that must dissociate before DNA binding. TFIID dimers formed through self-association of the TATA-binding polypeptide (TBP) subunit and could be immunoprecipitated with antibodies to TAF(II)250, the core subunit of TFIID. Chemical cross-linking experiments in HeLa cells revealed the presence of TBP dimers in vivo. These findings suggest that dimerization through TBP is the physiological state of TFIID when not bound to DNA. Thus, the inefficiency of TFIID binding to a promoter may be partly attributable to the competitive effect of dimerization.
authors.affiliation: Center for Gene Regulation, Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA 16802, USA.
authors.forename: A K
authors.initials: AK
authors.lastname: Taggart
authors.forename: B F
authors.initials: BF
authors.lastname: Pugh
mesh_terms: D001483:Base Sequence; D001704:Biopolymers; D002850:Chromatography, Gel; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism; D006367:HeLa Cells; D051548:Histone Acetyltransferases; D006801:Humans; D015151:Immunoblotting; D008956:Models, Chemical; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D016385:TATA Box; D035381:TATA-Binding Protein Associated Factors; D035181:TATA-Box Binding Protein; D035362:Transcription Factor TFIID; D014157:Transcription Factors / Q000737:chemistry* / Q000378:metabolism
chemical_list: D001704:Biopolymers; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D011994:Recombinant Proteins; D035381:TATA-Binding Protein Associated Factors; D035181:TATA-Box Binding Protein; D035362:Transcription Factor TFIID; D014157:Transcription Factors; D004247:DNA; D051548:Histone Acetyltransferases; C069001:TATA-binding protein associated factor 250 kDa