TATA box-binding protein (TBP) is a constituent of the polymerase I-specific transcription initiation factor TIF-IB (SL1) bound to the rRNA promoter and shows differential sensitivity to TBP-directed reagents in polymerase I, II, and III transcription factors.
The role of the Acanthamoeba castellanii TATA-binding protein (TBP) in transcription was examined. Specific antibodies against the nonconserved N-terminal domain of TBP were used to verify the presence of TBP in the fundamental transcription initiation factor for RNA polymerase I, TIF-IB, and to demonstrate that TBP is part of the committed initiation complex on the rRNA promoter. The same antibodies inhibit transcription in all three polymerase systems, but they do so differentially. Oligonucleotide competitors were used to evaluate the accessibility of the TATA-binding site in TIF-IB, TFIID, and TFIIIB. The results suggest that insertion of TBP into the polymerase II and III factors is more similar than insertion into the polymerase I factor.
Radebaugh
C A
CA
Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins 80523.
Matthews
J L
JL
Geiss
G K
GK
Liu
F
F
Wong
J M
JM
Bateman
E
E
Camier
S
S
Sentenac
A
A
Paule
M R
MR
D000048:Acanthamoeba / Q000235:genetics* / Q000378:metabolism*; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D016054:DNA, Protozoan / Q000235:genetics; D004268:DNA-Binding Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes; D035463:Pol1 Transcription Initiation Complex Proteins; D011401:Promoter Regions, Genetic; D012318:RNA Polymerase I / Q000378:metabolism; D012319:RNA Polymerase II / Q000378:metabolism; D012320:RNA Polymerase III / Q000378:metabolism; D016053:RNA, Protozoan / Q000235:genetics; D012335:RNA, Ribosomal / Q000235:genetics; D016385:TATA Box; D035181:TATA-Box Binding Protein; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic
D016054:DNA, Protozoan; D004268:DNA-Binding Proteins; D015345:Oligonucleotide Probes; D035463:Pol1 Transcription Initiation Complex Proteins; D016053:RNA, Protozoan; D012335:RNA, Ribosomal; D035181:TATA-Box Binding Protein; D014157:Transcription Factors; C063660:transcription initiation factor TIF-IB; D012319:RNA Polymerase II; D012318:RNA Polymerase I; D012320:RNA Polymerase III