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)

Mouse F9 embryonic carcinoma (EC) cells differentiate in culture to parietal endoderm (PE) cells upon induction with retinoic acid and cyclic AMP. In the course of this process, the expression of polymerase III transcripts, e.g., 5S rRNA and U6 small nuclear RNA, is dramatically reduced. This reduction of endogenous RNA content is accompanied by a loss of transcriptional capacity in cell extracts from PE cells. Partial purification of such extracts reveals that the DNA-binding activity of transcription factor PBP, binding specifically to the proximal sequence element (PSE) sequence of vertebrate U6 genes, is significantly reduced. This finding is corroborated by a loss in the transcriptional activity of this factor in reconstitution assays with partially purified polymerase III transcription components. In contrast, the activity of TFIIIA and TFIIIB and the amount of free TATA-binding protein remain unchanged during the differentiation process analyzed here. These data show for the first time that the PSE-binding protein PBP is essentially involved in the differential regulation of polymerase III genes governed by external promoters.
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PMID:The activity of transcription factor PBP, which binds to the proximal sequence element of mammalian U6 genes, is regulated during differentiation of F9 cells. 756 41

It has previously been reported that transcription in vivo of the tRNA(Sec) gene requires three promoter elements, a PSE and a TATA-box upstream of the coding region which are functionally interchangeable with the U6 snRNA gene counterparts and an internal B-block, resembling that of classical tRNA genes (1). We have established an in vitro transcription system from HeLa cells in which three factors, which are either essential for or stimulate transcription were identified. Apart from the TATA-binding protein TBP, the PSE-binding protein PBP was found to be essentially required for expression of the gene. Depletion of PBP from cell extracts by PSE-oligonucleotides abolished tRNA(Sec) transcription, which could be reconstituted by readdition of partially purified PBP. Addition of increasing amounts of recombinant human TBP to an S100 extract stimulated transcription of the tRNA(Sec), the mouse U6 snRNA and the human Y3 genes, an effect which was not observed in the case of a TATA-less tRNA gene. Purified human TFIIA strongly stimulated tRNA(Sec) transcription in a fashion depending on the concentration of TBP. Surprisingly, partially purified TFIIIC was shown to be dispensable for transcription in vitro and unable to bind the B-block of this gene in vitro, although its sequence matches the consensus for this element. Collectively, these data suggest that the mechanism by which transcription complexes are formed on the tRNA(Sec) gene is dramatically different from that observed for classical tRNA genes and much more resembles that observed for externally controlled pol III genes.
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PMID:Transcription factors required for the expression of Xenopus laevis selenocysteine tRNA in vitro. 812 3

Eukaryotic transcriptional regulatory signals, defined as core and activator promoter elements, have yet to be identified in the earliest diverging group of eukaryotes, the primitive protozoans, which include the Trypanosomatidae family of parasites. The divergence within this family is highlighted by the apparent absence of the "universal" transcription factor TATA-binding protein. To understand gene expression in these protists, we have investigated spliced leader RNA gene transcription. The RNA product of this gene provides an m(7)G cap and a 39-nucleotide leader sequence to all cellular mRNAs via a trans-splicing reaction. Regulation of spliced leader RNA synthesis is controlled by a tripartite promoter located exclusively upstream from the transcription start site. Proteins PBP-1 and PBP-2 bind to two of the three promoter elements in the trypanosomatid Leptomonas seymouri. They represent the first trypanosome transcription factors with typical double-stranded DNA binding site recognition. These proteins ensure efficient transcription. However, accurate initiation is determined an initiator element with a a loose consensus of CYAC/AYR (+1), which differs from that found in metazoan initiator elements as well as from that identified in one of the earliest diverging protozoans, Trichomonas vaginalis. Trypanosomes may utilize initiator element-protein interactions, and not TATA sequence-TATA-binding protein interactions, to direct proper transcription initiation by RNA polymerase II.
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PMID:Transcription initiation at the TATA-less spliced leader RNA gene promoter requires at least two DNA-binding proteins and a tripartite architecture that includes an initiator element. 1054 23