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Query: UNIPROT:P20226 (TATA-binding protein)
 1,297 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The gene encoding the TATA-binding protein (PkTBP) from a hyperthermophilic archaeon, Pyrococcus sp. KOD1 (Pk), was cloned and sequenced. An open reading frame with homology to the conserved C-terminal core region of eukaryotic TBP was expressed in Escherichia coli. Specific DNA-binding activity of the recombinant PkTBP (190 amino acids, 21.36 kDa) was also demonstrated. Although it was composed of a structurally direct repeat sequence which is similar to eukaryotic TBP, the total net charge of archaeal TBP was amazingly negative (calculated isoelectric point (pI) was 4.66 and experimentally estimated pI was 4.8). A series of five Glu residues was found at the C terminus of archaeal TBP. These data strongly suggest that a positively charged protein is also involved in the transcription initiation event which might stabilize the structure of the genomic DNA under high-growth-temperature conditions.
Gene 1995 Dec 01
PMID:An abnormally acidic TATA-binding protein from a hyperthermophilic archaeon. 852 78

Previous studies demonstrated that mutations in the Saccharomyces cerevisiae NOT genes increase transcription from TATA-less promoters. In this report, I show that in contrast, mutations in the yeast MOT1 gene decrease transcription from TATA-less promoters. I also demonstrate specific genetic interactions between the Not complex, Mot1p, and another global regulator of transcription in S. cerevisiae, Spt3p. Five distinct genetic interactions have been established. First, a null allele of SPT3, or a mutation in SPT15 that disrupts the interaction between Spt3p and TATA-binding protein (TBP), allele specifically suppressed the not1-2 mutation. Second, in contrast to not mutations, mutations in MOT1 decreased HIS3 and HIS4 TATA-less transcription. Third, not mutations suppressed toxicity due to overexpression of TBP in mot1-1 mutants. Finally, overexpression of SPT3 caused a weak Not- mutant phenotype in mot1-1 mutants. Collectively, these results suggest a novel type of transcriptional regulation whereby the distribution of limiting TBP (TFIID) on weak and strong TBP-binding core promoters is regulated: Mot1p releases stably bound TBP to allow its redistribution to low-affinity sites, and the Not proteins negatively regulate the activity of factors such as Spt3p that favor distribution of TBP to these low-affinity sites.
Mol Cell Biol 1996 Dec
PMID:The NOT, SPT3, and MOT1 genes functionally interact to regulate transcription at core promoters. 894 21

We have investigated the role of the TATA-binding protein (TBP) in modulating RNA polymerase (Pol) III gene activity. Epitope-tagged TBP (e-TBP) was both transiently and stably transfected in Drosophila Schneider S-2 cells to increase the total cellular level of TBP. Analysis of the transcripts synthesized from cotransfected tRNA and U6 RNA genes revealed that both types of RNA Pol III promoters were substantially stimulated by an increase in e-TBP in a dose-dependent manner. Furthermore, a TBP-dependent increase in the levels of endogenous tRNA transcripts was produced in the stable line induced to express the e-TBP. We further determined whether the ability of increased TBP to induce RNA Pol III gene expression was due to a direct effect of increased TBP complexes on RNA Pol III gene promoters or an indirect consequence of enhanced expression of RNA Pol II genes. A TBP expression plasmid (e-TBP332), containing a mutation within the highly conserved carboxy-terminal domain, was both transiently and stably transfected into S-2 cells. e-TBP332 augmented the transcription from two RNA Pol II gene promoters indistinguishably from that observed when e-TBP was expressed. In contrast, e-TBP332 was completely defective in its ability to stimulate either the tRNA or U6 RNA gene promoters. In addition, increasing levels of a truncated TBP protein containing only the carboxy-terminal region failed to induce either the tRNA or U6 RNA gene promoter, whereas it retained its ability to stimulate an RNA Pol II promoter. Thus, the TBP-dependent increase in RNA Pol II gene activity is not sufficient for enhanced RNA Pol III gene transcription; rather, a direct effect on RNA Pol III promoters is required. Furthermore, these results provide the first direct evidence that the amino-terminal region of TBP is important for the formation or function of TBP-containing complexes utilized by TATA-less and TATA-containing RNA Pol III promoters. Together, these studies demonstrate that TBP is limiting for the expression of both classes of RNA Pol III promoters in Drosophila cells and implicate an important role for TBP in regulating RNA Pol III gene expression.
Mol Cell Biol 1996 Dec
PMID:TATA-binding protein is limiting for both TATA-containing and TATA-lacking RNA polymerase III promoters in Drosophila cells. 894 46

Wild-type p53 represses Alu template activity in vitro and in vivo. However, upstream activating sequence elements from both the 7SL RNA gene and an Alu source gene relieve p53-mediated repression. p53 also represses the template activity of the U6 RNA gene both in vitro and in vivo but has no effect on in vitro transcription of genes encoding 5S RNA, 7SL RNA, adenovirus VAI RNA, and tRNA. The N-terminal activation domain of p53, which binds TATA-binding protein (TBP), is sufficient for repressing Alu transcription in vitro, and mutation of positions 22 and 23 in this region impairs p53-mediated repression of an Alu template both in vitro and in vivo. p53's N-terminal domain binds TFIIIB, presumably through its known interaction with TBP, and mutation of positions 22 and 23 interferes with TFIIIB binding. These results extend p53's transcriptional role to RNA polymerase III-directed templates and identify an additional level of Alu transcriptional regulation.
Mol Cell Biol 1996 Dec
PMID:p53 inhibits RNA polymerase III-directed transcription in a promoter-dependent manner. 894 63

TATA-binding protein (TBP) is a central component for transcriptional regulation and is a target for various transcription regulators. Using histidine-tagged TBP as a ligand for affinity-purification of proteins bound to TBP, we purified a 120-kD protein, termed TBP-interacting protein 120 (TIP120), from rat liver nuclear extracts. The entire cDNA sequence of TIP120 contained an open reading frame encoding a novel polypeptide of 1230 amino acids. The recombinant TIP120 interacted directly with TBP under a physiological condition in vitro. Immunoprecipitation analysis indicated that TIP120 was associated with TBP in nuclear extracts. Interestingly, the N-terminal region of TIP120 exhibited sequence similarity to that of Drosophila TAF80, which was shown to bind directly to TBP. This novel TBP-binding protein is considered to participate in transcription regulation through the interaction with TBP.
Biochem Biophys Res Commun 1996 Dec 13
PMID:Molecular cloning of a novel 120-kDa TBP-interacting protein. 895 46

Transcription by RNA polymerase III (pol III) in yeast requires the assembly of an initiation complex comprising the TATA-binding protein (TBP), a 90-kDa polypeptide (TFIIIB90), and a 70-kDa polypeptide (TFIIIB70). TFIIIB70 interacts with TBP, a unique pol III subunit, C34, and the 131-kDa subunit of the pol III-specific complex, TFIIIC. TFIIIB70 was expressed in Escherichia coli and purified to homogeneity. The specific transcription activity of rTFIIIB70 is 22-58% that of the native yeast and in vitro synthesized factor. However, only a small fraction (0.07-0.32%) of the TFIIIB70 from these sources results in the synthesis of full-length RNA. The data suggest that TFIIIB70 function may be limited by an unfavorable recruitment equilibrium into the preinitiation complex. Quantitative DNase I "footprint" titrations of yeast TBP to the adenovirus major late promoter were conducted at a series of constant TFIIIB70 concentrations. A value of -0.7 +/- 0.2 kcal/mol was determined for the cooperative free energy of formation of the TBP.TFIIIB70.DNA complex at concentrations of TFIIIB70 sufficient to partition all of the binding cooperativity to the TBP binding isotherm. A Kd of 44 +/- 23 nM characterizes the TFIIIB70 concentration dependence of the TBP.TFIIIB70 cooperativity. The relationship deltalog K/deltalog (TFIIIB70) is consistent with the linkage of a single molecule of TFIIIB70 with the TBP-promoter binding reaction.
J Biol Chem 1996 Dec 20
PMID:Expression and purification of the RNA polymerase III transcription specificity factor IIIB70 from Saccharomyces cerevisiae and its cooperative binding with TATA-binding protein. 895 1

In eukaryotic cells the TATA-binding protein (TBP) associates with other proteins known as TBP-associated factors (TAFs) to form multisubunit transcription factors important for gene expression by all three nuclear RNA polymerases. Computer searching of the complete Saccharomyces cerevisiae genome revealed five previously unidentified yeast genes with significant sequence similarity to known human and Drosophila RNA polymerase II TAFs. Each of these genes is essential for viability. A sixth essential gene (FUN81) has previously been noted to be similar to human TAFII18. Coimmunoprecipitation experiments show that all six proteins are associated with TBP, demonstrating that they are true TAFs. Furthermore, these proteins are present in complexes containing the TAFII130 subunit, indicating that they are components of TFIID. Based on their predicted molecular weights, these genes have been designated TAF67, TAF61(68), TAF40, TAF23(25), TAF19(FUN81), and TAF17. Yeast TAF61 is significantly larger than its higher eukaryotic homologues, and deletion analysis demonstrates that the evolutionarily conserved, histone-like domain is sufficient and necessary to support viability.
Proc Natl Acad Sci U S A 1996 Dec 10
PMID:Yeast homologues of higher eukaryotic TFIID subunits. 896 9

Rapid evolution of ribosomal RNA (rRNA) gene promoters often prevents their recognition in a foreign species. Unlike animal systems, we show that foreign plant rRNA gene promoters are recognized in an alien species, but tend to program transcription by a different polymerase. In plants, RNA polymerase I transcripts initiate at a TATATA element (+1 is underlined) important for promoter strength and start-site selection. However, transcripts initiate from +32 following transfection of a tomato promoter into Arabidopsis. The rRNA gene promoter of a more closely related species, Brassica oleracea, programs both +1 and +29 transcription. A point mutation at +2 improving the identity between the Brassica and Arabidopsis promoters increases +1 transcription, indicating a role for the initiator element in species-specificity. Brassica +29 transcripts can be translated to express a luciferase reporter gene, implicating RNA polymerase II. TATA mutations that disrupt TATA-binding protein (TBP) interactions inhibit +29 transcription and luciferase expression. Co-expressed TBP proteins bearing compensatory mutations restore +29 transcription and luciferase activity, suggesting a direct TBP-TATA interaction. Importantly, +1 transcription is unaffected by the TATA mutations, suggesting that in the context of pol I recognition, the TATA-containing initiator element serves a function other than TBP binding.
Nucleic Acids Res 1996 Dec 01
PMID:Species-specificity of rRNA gene transcription in plants manifested as a switch in RNA polymerase specificity. 897 59

Nuclear transcription is repressed when eukaryotic cells enter mitosis. Using Xenopus egg extracts shifted to the mitotic state with recombinant cyclin B1 protein, we have been able to reproduce mitotic repression of transcription in vitro. Active RNA polymerase III transcription is observed in interphase extracts in the absence of added cyclin, but is strongly repressed by the induction of cdc2/cyclin B (maturation/mitosis promoting factor, MPF) kinase activity in the mitotic extract. Studies with protein kinase inhibitors show that protein phosphorylation is required for repression. Add-back experiments indicate that repression of class III gene transcription is due to inactivation of the transcription factor TFIIIB. TFIIIB is composed of the TATA-box binding protein (TBP) and TBP-associated factors of 75 and 92 kDa. In the present study, we show that TBP and a polypeptide of 92 kDa are substrates of the mitotic kinase in highly purified TF- IIIB fractions. We also show that a phosphatase present in the Xenopus egg extract can reactivate transcription after repression by the mitotic kinases. This result suggests a mechanism for reactivation of transcription after exit from mitosis into the G1 phase of the cell cycle. As for pol III genes, purified cdc2/cyclin B kinase is sufficient to inhibit transcription by RNA polymerase II in a reconstituted transcription system containing the basal transcription factors and polymerase.
Exp Cell Res 1996 Dec 15
PMID:Repression of RNA polymerase II and III transcription during M phase of the cell cycle. 898 11

This study analyzes the three-dimensional structure of the TATA-box binding protein (TBP) from the hyperthermophilic archaea Pyrococcus woesei. The crystal structure of P. woesei TBP (PwTBP) was solved at 2.2 A by X-ray diffraction and as expected from sequence homology (36% to 41% identical to eukaryotic TBPs) its overall structure is very similar to eukaryotic TBPs. The thermal unfolding transition temperature of this protein was measured by differential scanning calorimetry to be 101 degrees C, which is more than 40 degrees C higher than that of yeast TBP. Preliminary titration calorimetry data show that the affinity of PwTBP for its DNA target, unlike its eukaryotic counterparts, is enhanced by increasing the temperature and salt concentration. The structure reveals possible explanations for this thermostability and these unusual DNA binding properties. The crystal structure of this hyperthermostable protein was compared to its mesophilic homologs and analyzed for differences in the native structure that may contribute to thermostability. Differences found were: (1) a disulfide bond not found in mesophilic counterparts; (2) an increased number of surface electrostatic interactions; (3) more compact protein packing. The presumed DNA binding surface of PwTBP, like its eukaryotic counterparts, is hydrophobic but the electrostatic profile surrounding the protein is relatively neutral compared to the asymmetric positive potential that surrounds eukaryotic TBPs. The total reliance on a hydrophobic interface with DNA may explain the enhanced affinity of PwTBP for its DNA promoter at higher temperatures and increased salt concentration.
J Mol Biol 1996 Dec 20
PMID:The crystal structure of a hyperthermophilic archaeal TATA-box binding protein. 900 Jun 31


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