TAF(II)170 interacts with the concave surface of TATA-binding protein to inhibit its DNA binding activity.
The human RNA polymerase II transcription factor B-TFIID consists of TATA-binding protein (TBP) and the TBP-associated factor (TAF) TAF(II)170 and can rapidly redistribute over promoter DNA. Here we report the identification of human TBP-binding regions in human TAF(II)170. We have defined the TBP interaction domain of TAF(II)170 within three amino-terminal regions: residues 2 to 137, 290 to 381, and 380 to 460. Each region contains a pair of Huntington-elongation-A subunit-Tor repeats and exhibits species-specific interactions with TBP family members. Remarkably, the altered-specificity TBP mutant (TBP(AS)) containing a triple mutation in the concave surface is defective for binding the TAF(II)170 amino-terminal region of residues 1 to 504. Furthermore, within this region the TAF(II)170 residues 290 to 381 can inhibit the interaction between Drosophila TAF(II)230 (residues 2 to 81) and TBP through competition for the concave surface of TBP. Biochemical analyses of TBP binding to the TATA box indicated that TAF(II)170 region 290-381 inhibits TBP-DNA complex formation. Importantly, the TBP(AS) mutant is less sensitive to TAF(II)170 inhibition. Collectively, our results support a mechanism in which TAF(II)170 induces high-mobility DNA binding by TBP through reversible interactions with its concave DNA binding surface.
Pereira
L A
LA
Department of Physiological Chemistry, University Medical Center Utrecht, 3508 AB Utrecht, The Netherlands.
van der Knaap
J A
JA
van den Boom
V
V
van den Heuvel
F A
FA
Timmers
H T
HT
D000595:Amino Acid Sequence; D000818:Animals; D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004330:Drosophila; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D010957:Plasmids / Q000378:metabolism; D011233:Precipitin Tests; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D035381:TATA-Binding Protein Associated Factors; D035181:TATA-Box Binding Protein; D035362:Transcription Factor TFIID; D014157:Transcription Factors / Q000378:metabolism*; D019473:Transcription Factors, TFII / Q000378:metabolism*; D014158:Transcription, Genetic; D020798:Two-Hybrid System Techniques
C109035:BTAF1 protein, human; D004268:DNA-Binding Proteins; D011506:Proteins; D011993:Recombinant Fusion Proteins; D035381:TATA-Binding Protein Associated Factors; D035181:TATA-Box Binding Protein; D035362:Transcription Factor TFIID; D014157:Transcription Factors; D019473:Transcription Factors, TFII; D004247:DNA; D005982:Glutathione Transferase