Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20226 (TATA-binding protein)
 1,297 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In humans, transcription factor IIIB (TFIIIB)-alpha governs basal transcription from small nuclear RNA genes by RNA polymerase III (pol III). One of the components of this complex, BRFU/TFIIIB50, is specific for these promoters, whereas TATA-binding protein (TBP) and hB" are required for pol III transcription from both gene external and internal promoters. We show that hB" is specifically recruited to a promoter-bound TBP.BRFU complex, which we have previously demonstrated as forming on TATA-containing templates. The N-terminal region of BRFU, containing a zinc ribbon domain, acts as a damper of hB" binding. TBP deactivates this negative mechanism through protein-protein contacts with both BRFU and hB", which may then promote their cooperative binding to form TFIIIB-alpha. In addition, we have identified a GC-rich sequence downstream from the TATA box (the BURE) which, depending on the strength of TATA box, can either enhance BRFU binding to the TBP.DNA complex or hB" association with the BRFU.TBP.DNA complex, and subsequently stimulate pol III transcription. Moreover, mutation of the BURE reduces pol III transcription and induces transcription by RNA polymerase II from the U2 gene promoter carrying a minimal TATA box.
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PMID:Assembly of human small nuclear RNA gene-specific transcription factor IIIB complex de novo on and off promoter. 1201 23

Recruitment of TATA-binding protein (TBP) is central to activation of transcription by RNA polymerase II (pol II). This depends upon co-activator proteins including TBP-associated factors (TAFs). Yeast Mot1p was identified as a general transcriptional repressor in genetic screens and is also found associated with TBP. To obtain insight into Mot1p function in vivo, we determined the mRNA expression profile of the mot1-1 temperature-sensitive (Ts) strain. Unexpectedly, this indicated that Mot1p mostly plays a positive role for transcription. For one potential activation target, HXT2, we analyzed promoter recruitment of Mot1p, TBP, Taf1p (Taf130p) and pol II by chromatin immunoprecipitation assays. Whereas TBP becomes stably associated upon activation of the HXT2 and HXT4 promoters, Mot1p showed only a transient association. TBP recruitment was compromised in two different mot1 mutant strains, but was only moderately affected in a taf1 Ts strain. Together, our data indicate that Mot1p can assist in recruitment of TBP on promoters during gene activation in vivo.
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PMID:Mot1p is essential for TBP recruitment to selected promoters during in vivo gene activation. 1235 33

Archaea have a eukaryotic type of transcriptional machinery containing homologues of the transcription factors TATA-binding protein (TBP) and TFIIB (TFB) and a pol II type of RNA polymerase, whereas transcriptional regulators identified in archaeal genomes have bacterial counterparts. We describe here a novel regulator of heat shock response, Phr, from the hyperthermophilic archaeon Pyrococcus furiosus that is conserved among Euryarchaeota. The protein specifically inhibited cell-free transcription of its own gene and from promoters of a small heat shock protein, Hsp20, and of an AAA(+) ATPase. Inhibition of transcription was brought about by abrogating RNA polymerase recruitment to the TBP/TFB promoter complex. Phr bound to a 29-bp DNA sequence overlapping the transcription start site. Three sequences conserved in the binding sites of Phr, TTTA at -10, TGGTAA at the transcription start site, and AAAA at position +10, were required for Phr binding and are proposed as consensus regulatory sequences of Pyrococcus heat shock promoters. Shifting the growth temperature from 95 to 103 degrees C caused a dramatic increase of mRNA levels for the aaa(+) atpase and phr genes, but expression of the Phr protein was only weakly stimulated. Our findings suggest that heat shock response in Archaea is negatively regulated by a mechanism involving binding of Phr to conserved sequences.
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PMID:A novel archaeal transcriptional regulator of heat shock response. 1238 24

The 180-amino acid core of the TATA-binding protein (TBPcore) is conserved from Archae bacteria to man. Vertebrate TBPs contain, in addition, a large and highly conserved N-terminal region that is not found in other phyla. We have generated a line of mice in which the tbp allele is replaced with a version, tbp(Delta N), which lacks 111 of 135 N-terminal amino acid residues. Most tbp(Delta N/Delta N) fetuses die in midgestation. To test whether a disruption of general cellular processes contributed to this fetal loss, primary fibroblast cultures were established from +/+, Delta N/+, and Delta N/Delta N fetuses. The cultures exhibited no genotype-dependent differences in proliferation or in expression of the proliferative markers dihydrofolate reductase (DHFR) mRNA (S phase-specific) and cdc25B mRNA (G(2)-specific). The mutation had no effect on transcription initiation site fidelity by either RNA polymerase II (pol II) or pol III. Moreover, the mutation did not cause differences in levels of U6 RNA, a pol III-dependent component of the splicing machinery, in mRNA splicing efficiency, in expression of housekeeping genes from either TATA-containing or TATA-less promoters, or in global gene expression. Our results indicated that general eukaryotic cell functions are unaffected by deletion of these vertebrate-specific sequences from TBP. Thus, all activities of this polypeptide domain must either be compensated for by redundant activities or be restricted to situations that are not represented by primary fibroblasts.
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PMID:Fundamental cellular processes do not require vertebrate-specific sequences within the TATA-binding protein. 1247 Oct 23

Mediator is a general cofactor implicated in the functions of many transcriptional activators. Although Mediator with different protein compositions has been isolated, it remains unclear how Mediator facilitates activator-dependent transcription, independent of its general stimulation of basal transcription. To define the mechanisms of Mediator function, we isolated two forms of human Mediator complexes (Mediator-P.5 and Mediator-P.85) and demonstrated that Mediator-P.5 clearly functions by enhancing activator-mediated recruitment of RNA polymerase II (pol II), whereas Mediator-P.85 works mainly by stimulating overall basal transcription. The coactivator function of Mediator-P.5 was not impaired when TATA-binding protein (TBP) was used in place of TFIID, but it was abolished when another general cofactor, PC4, was omitted from the reaction or when Mediator-P.5 was added after pol II entry into the preinitiation complex. Moreover, Mediator- P.5 is able to enhance TBP binding to the TATA box in an activator-dependent manner. Our data provides biochemical evidence that Mediator functions by facilitating activator-mediated recruitment of pol II and also promoter recognition by TBP, both of which can occur in the absence of TBP-associated factors in TFIID.
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PMID:Human mediator enhances activator-facilitated recruitment of RNA polymerase II and promoter recognition by TATA-binding protein (TBP) independently of TBP-associated factors. 1291 44

The TATA-binding protein (TBP) is involved in all nuclear transcription. We show that a common site on TBP is used for transcription initiation complex formation by RNA polymerases (pols) II and III. TBP, the transcription factor IIB (TFIIB)-related factor Brf1 and the pol III-specific factor Bdp1 constitute TFIIIB. A photochemical cross-linking approach was used to survey a collection of human TBP surface residue mutants for their ability to form TFIIIB-DNA complexes reliant on only the TFIIB-related part of Brf1. Mutations impairing complex formation and transcription were identified and mapped on the surface of TBP. The most severe effects were observed for mutations in the C-terminal stirrup of TBP, which is the principal site of interaction between TBP and TFIIB. Structural modeling of the Brf1-TBP complex and comparison with its TFIIB-TBP analog further rationalizes the close resemblance of the TBP interaction with the N-proximal part of Brf1 and TFIIB, and establishes the conserved usage of a TBP surface in pol II and pol III transcription for a conserved function in the initiation of transcription.
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PMID:A common site on TBP for transcription by RNA polymerases II and III. 1451 49

Regulation of RNA polymerase II (pol II) transcription is a highly dynamic process requiring the coordinated interaction of an array of regulatory proteins. Central to this process is the TATA-binding protein (TBP), the key component of the multiprotein complex TFIID. Interaction of TBP with core promoters nucleates the assembly of the preinitiation complex and subsequent recruitment of pol II. Despite recent advances in our understanding of the dynamic nature of the pol II transcription apparatus, the dynamics of TBP function on pol II promoters has remained largely unexplored. Human BTAF1 (TAF(II)170/TAF-172) and its yeast ortholog, Mot1p, are evolutionarily conserved members of the SNF2-like family of ATPase proteins. Genetic identification of Mot1p as a repressor of pol II transcription was supported by findings that Mot1p and BTAF1 could dissociate TBP from TATA DNA complexes using the energy of ATP hydrolysis. Recent data have revealed new aspects of BTAF1 and Mot1p as positive regulators of TBP function in the pol II system and have described new observations relating to their molecular mechanism of action. We review these data in the context of previous findings with particular attention paid to how human BTAF1 and Mot1p may dynamically regulate TBP function on pol II promoters in cells.
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PMID:Roles for BTAF1 and Mot1p in dynamics of TATA-binding protein and regulation of RNA polymerase II transcription. 1455 59

RNA polymerase II (pol II) transcribes the most varied group of genes and is present in hypo- and hyperphosphorylated forms, with residues Ser(2) and Ser(5) of the C-terminal domain (CTD) of the largest subunit as main targets of phosphorylation. The elongating (active) form is phosphorylated on Ser(2) and can be specifically recognized with the H5 antibody. It has been found in different nuclear distributions: in discrete sites throughout the nucleoplasm, consistent with a role in transcription, and/or concentrated in "splicing speckles", a nuclear compartment mostly devoid of transcriptional activity. Here, we assess the effects of cell fixation and permeabilization on the distribution of polymerase II and correlate its distribution with the preservation of cellular ultrastructure. We show that phospho-Ser(2) polymerase II can redistribute to, or be differentially retained in, "speckles" in conditions that do not preserve cellular ultrastructure. The fixation protocols that disrupt polymerase II distribution also cause partial or total loss of TATA-binding protein, Sm antigen and PML staining in PML bodies, and have no noticeable effect in the labeling of SC35 in "splicing speckles" or coilin in Cajal bodies. When nuclear ultrastructure is preserved, phospho-Ser(2) polymerase II is found in discrete sites throughout the nucleoplasm, without visible enrichment within splicing speckles. A minor proportion of the total amount of the phospho-Ser(2) form is present in these domains.
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PMID:Fixation-induced redistribution of hyperphosphorylated RNA polymerase II in the nucleus of human cells. 1509 44

TATA-binding protein (TBP)-related factor 2 (TRF2) is one of four closely related RNA polymerase II transcription factors. We compared the intracellular localizations of TBP and TRF2 during the cell cycle and mitosis in HeLa cells. We show that during interphase, endogenous or exogenously expressed TRF2 is located almost exclusively in the nucleolus in HeLa or Cos cells. TRF2 localization is not affected by stress or mitotic stimuli, but TRF2 is rapidly released from the nucleolus upon inhibition of pol I transcription or treatment by RNase. These results suggest that localization of HeLa TRF2 requires a nucleolar-associated RNA species. In contrast, in 3T3 fibroblast cells, exogenously expressed TRF2 localizes to the nucleoplasm. Constitutive expression of ectopic TRF2 in 3T3 cells leads to a prolonged S phase of the cell cycle and reduced proliferation. Together with previous data, our results highlight the cell-specific localization and functions of TRF2. Furthermore, we show that during cell division, HeLa TRF2 and TBP are localized in the mitotic cytoplasm and TRF2 relocalizes into the nascent nucleoli immediately after mitosis, whereas TBP reassociates with the chromatin. Although partially contradictory results have been reported, our data are consistent with a model where only small proportion of the cellular TBP remains associated with specific promoter loci during mitosis.
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PMID:Cell-specific nucleolar localization of TBP-related factor 2. 1526 81

TFIIF is a general transcription factor (GTF) that binds to RNA polymerase II (pol II) for subsequent recruitment of pol II to a promoter. TFIIF of Saccharomyces cerevisiae contains a small subunit, designated Tfg3, in addition to two conserved subunits, TFIIFalpha (Tfg1) and TFIIFbeta (Tfg2). In this study, we characterized Tfg3 of Schizosaccharomyces pombe. Using Tfg3 fused to green fluorescent protein (GFP), we found that Tfg3 is located in nuclei, and it is assembled into the C-terminal domain phosphatase (Fcp1)/TFIIF/pol II complex via interactions with TFIIFalpha and TFIIFbeta. As in the case of S.cerevisiae, Tfg3 in S.pombe forms part of another GTF, namely TFIID. The TFIID complex isolated from S.pombe that had been cultured at elevated temperatures included increased levels of Tfg3. The interaction of recombinant Tfg3 with TATA-binding protein (TBP), the central subunit of TFIID, was temperature-dependent. Moreover, a mutant of S.pombe that lacked the gene for Tfg3 was sensitive to a battery of stresses including temperature up-shift. Starting from a mutant with tfg3- mutation, we isolated five species of multicopy suppressors. Expression levels of the suppressor genes were lower in the mutant cell than in wild-type cell at an elevated temperature. Taken together, we propose that Tfg3 is involved in transcriptional regulation under stress conditions, in particular, at high temperatures.
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PMID:Tfg3, a subunit of the general transcription factor TFIIF in Schizosaccharomyces pombe, functions under stress conditions. 1561 56


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