TFIID, dTBP, TFIIDτ, TATA box-binding protein, dTFIID
Gene model reviewed during 5.51
There is only one protein coding transcript and one polypeptide associated with this gene
Belongs to the TFIID complex which is composed of TATA binding protein (Tbp) and a number of TBP-associated factors (Tafs). Binds DNA as monomer. Interacts with TFIIA-L heterotrimer. Interacts with Taf1, Taf2, Taf5 and Taf12.
Click to get a list of regulatory features (enhancers, TFBS, etc.) and gene disruptions (point mutations, indels, etc.) within or overlapping Dmel\Tbp using the Feature Mapper tool.
Tbp protein is detected in the nuclei of somatic cells of ovaries including apical terminal filament cells, inner sheath cells, and follicular cells of the developing cysts. It is also detected in nurse cells but not in the oocyte. Tbp protein is detected in the spermatogonium, decreases rapidly in primary spermatocytes and is not detected in mature primary spermatocyte or in later stages of spermatogenesis.
GBrowse - Visual display of RNA-Seq signalsView Dmel\Tbp in GBrowse 2
Please Note This section lists cDNAs and ESTs that fall within the genomic extent of the gene model, which may include cDNAs and ESTs of genes within introns, or of overlapping genes. Please see GBrowse for alignment of the cDNAs and ESTs to the gene model.
For each fully sequenced cDNA the DGRC maintains various forms of the cDNA (e.g tagged or untagged) in several different host vectors for subsequent cloning and expression in Drosophila and Drosophila cell lines.
DNA-protein interactions: genome-wide binding profile assayed for Tbp protein in Kc167 cells; see Chromatin_types_NKI collection report. Individual protein-binding experiments listed under "Samples" at GEO_GSE22069 (http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE22069).
dsRNA has been made from templates generated with primers directed against this gene.
Hsf interacts directly with the general transcription factor Tbp and these two factor bind cooperatively to heat shock promoters. Interaction of Hsf and Tbp is mediated by residues in both the amino and carboxy terminus of Hsf. The acidic domain of RpII215 associates with Tbp in vitro and is specifically displaced from Tbp upon addition of Hsf. Trl also interacts with Hsf to further stabilise Hsf binding to heat shock elements (HSEs).
Mutation at position 332 of Tbp renders it inactive for tRNA gene transcription in vitro.
TfIID binds to a conserved downstream basal promoter element (DPE) that is present in many TATA-box deficient promoters. The DPE acts in conjunction with the initiation site sequence to provide a binding site for TfIID in the absence of a TATA box to mediate transcription of TAT-less promoters.
In Schneider S-2 cells Tbp is limiting for the expression of both TATA-containing and TATA-lacking RNA polymerase III promoters.
The tandem Adh promoters are differentially transcribed in the embryo owing to critical differences in the core promoter elements. Reconstituted differential Adh promoter transcription in vitro provides evidence that selective Adh promoter utilization is mediated by a specific Tbp-TAF complex in combination with TfIIA. TAFs in the Tbp complex are required for discrimination between the Adh distal and proximal initiator elements.
A quadruple complex containing Tbp, Taf1, Taf4 and Taf6 mediates transcriptional synergism by bcd and hb, whereas triple Tbp-Taf complexes lacking one or other coactivator failed to support synergistic activation. The concerted action of multiple regulators with different coactivators helps to establish the pattern and level of segmentation gene transcription during development.
eve efficiently blocks, or "squelches", Tbp-enhanced transcription in cotransfected Schneider L2 cells. Squelching does not require eve DNA-binding sites on the reporter plasmids used, but is dependent on the presence of the eve repression domain.
The role of the two essential transcription components, TfIIIB and TfIIIC, in response to TPA treatment is studied; only TfIIIB activity is increased. Tbp activity is also increased. Results suggest that the induction of transcription is due to an increase in the activity of TfIIIB which results in an increase in the number of functional transcription complexes.
TFIID subunit proteins and the Tbp protein can interact in pairwise combinations with several subunits in a network of interactions within TFIID.
Taf1 contains at least two sites of interaction with Tbp. N terminal sites mediate strong physical interaction with Tbp and inhibit Tbp function. Interaction of the N terminal region with Tbp may directly control TATA-box binding.
Mutations downstream of the TATA element of the Hsp70 promoter reduce the binding of the Tbp gene product.
Purified TfIID, containing endogenous Tbp and at least seven TAFs is necessary and sufficient for Sp1 activation in a reconstituted transcription reaction.
A number of polypeptides (encoded by Taf1, Taf4, Taf5, Taf6, e(y)1 and Taf12) that are tightly associated with Tbp and are native TFIID components have been purified. Protein blotting experiments suggest that one of these proteins, Taf1, interacts directly with Tbp, while the association between Tbp and the other proteins is either weak or is an indirect association via Taf1.
In vitro expressed Taf4 protein interacts directly with Taf1 which itself interacts with Tbp, a complex of all three is suggested. Binding study with various mutants of Taf1 suggests that both Taf4 and Tbp interact with the N-terminal 352-amino acid portion of Taf1.
There is a weak but reproducible interaction between the products of the Tbp and Taf6 loci in vitro. Tbp, Taf1, Taf4 and Taf6 products can assemble into a mini-complex in vitro, showing that Taf6 and Taf4 occupy distinct binding sites on the C terminal part of Taf1.
See also Dynlacht, Cell 66:563 .
TfIID transcription factor is a multiprotein complex including TATA-binding protein (Tbp) and Tbp-associated factors (TAFs). Taf1 has been partially cloned and the assembly of a partial complex containing recombinant Tbp, Taf1 and Taf4 analysed. This triple complex supports activation of HeLa cell Sp1 and reveals specific interactions between Tbp, Taf1 and Taf4.
Overexpression of full length protein in cultured cells can enhance expression dramatically from a weak minimal TATA-containing promoter.