scholarly journals Taenia solium TAF6 and TAF9 binds to a putative Downstream Promoter Element present in TsTBP1 gene core promoter

2017 ◽  
Author(s):  
Oscar Rodríguez-Lima ◽  
Ponciano García-Gutierrez ◽  
Lucía Jimenez ◽  
Angel Zarain-Herzberg ◽  
Roberto Lazarini ◽  
...  

AbstractWe have cloned and characterized the gene encoding to Taenia solium TATA binding protein 1 (TsTBP1). It spans 1481 bp and its coding region is interrupted by four introns that possess the consensus donor/acceptor sequences. It produces a protein of 238 amino acids residues, which presented all the classical motives of the TBP1. On the core promoter region we identified putative binding sites for NF1, AP-1, YY1, TAF1/TAF2 and TAF6/TAF9, and the TSS that corresponds to an A+1. Southern and Northern blot analysis showed that TsTBP1 is encoded by a single gene, which produce a messenger of about 1.1 kbp with a higher differential expression in adult than the larval stage. Moreover, two putative TATA boxes were identified at -97 and -69 bp (relative to the TSS), likewise a Downstream Promoter Element (DPE) was located at +27 to +31 bp. EMSA experiments did not show any component of cysticerci nuclear extracts bound to the putative TATA-box elements; in contrast TAF6 and TAF9 bind to the DPE, showing that TsTBP1 is a TATA-less gen. On the other hand, TAF6 and TAF9 were localized on the nucleus from cells of T. crassiceps cysticerci bladder walls. By using the amino acid sequences of T. solium TAF6 (TsTAF6) and TAF9 (TsTAF9), we constructed a molecular model showing interaction between DPE-TsTAF6 and TsTAF6-TsTAF9. Finally, an in silico analysis of the core promoters of Taeniidae family genes showed that TATA-box and DPE are homologous to the mammalian elements, but not so the Inr. The low identity between TAF9 from cestodes and mammals open the possibility to use it as target to interrupt or modulate the transcription of TATA-box less genes in cestodes as a novel therapeutic strategy.Author summaryNeurocysticercosis still being a health problem in developing countries. Mexico reports a prevalence of 2.5% in the total patients from National Institute of Neurology and Neurosurgery. Several efforts have been made in different fields to study Taenia solium, and although the Genome Project has been published and released the genomic sequence of this parasite; the transcriptional mechanisms this organism remains unexplored. We isolated and characterized Taenia solium TATA-Binding Protein 1 (TsTBP1) gene and TBP-associated factor 6 and 9 cDNAs (TsTAF6 and TsTAF9, respectively). Our principal findings are: 1.- Identification of cis and trans elements in the core promoter of TsTBP1 gene. 2.- The TsTBP1 gene is a TATA-less promoter. 3.- Cloning of cDNAs to TsTAF6 and TsTAF9, 4.- Identification of a DPE in the core promoter of TsTBP1 gene, which interacts with TAF6 and TAF9, 5.- Construction of a molecular model that shows the interaction between DPE, TAF6, and TAF9; and 6.- A proposal of consensus sequences for TATA-box, Inr and DPE presented on Taeniidae family core promoters.

2007 ◽  
Vol 28 (1) ◽  
pp. 83-92 ◽  
Author(s):  
Stephanie D. Bush ◽  
Patricia Richard ◽  
James L. Manley

ABSTRACT We previously showed that reduced intracellular levels of the TATA binding protein (TBP), brought about by tbp heterozygosity in DT40 cells, resulted in a mitotic delay reflecting reduced expression of the mitotic regulator cdc25B but did not significantly affect overall transcription. Here we extend these findings in several ways. We first provide evidence that the decrease in cdc25B expression reflects reduced activity of the cdc25B core promoter in the heterozygous (TBP-het) cells. Strikingly, mutations in a previously described repressor element that overlaps the TATA box restored promoter activity in TBP-het cells, supporting the idea that the sensitivity of this promoter to TBP levels reflects a competition between TBP and the repressor for DNA binding. To determine whether cells might have mechanisms to compensate for fluctuations in TBP levels, we next examined expression of the two known vertebrate TBP homologues, TLP and TBP2. Significantly, mRNAs encoding both were significantly overexpressed relative to levels observed in wild-type cells. In the case of TLP, this was shown to reflect regulation of the core promoter by both TBP and TLP. Together, our results indicate that variations in TBP levels can affect the transcription of specific promoters in distinct ways, but overall transcription may be buffered by corresponding alterations in the expression of TBP homologues.


2000 ◽  
Vol 20 (13) ◽  
pp. 4754-4764 ◽  
Author(s):  
Alan K. Kutach ◽  
James T. Kadonaga

ABSTRACT The downstream promoter element (DPE) functions cooperatively with the initiator (Inr) for the binding of TFIID in the transcription of core promoters in the absence of a TATA box. We examined the properties of sequences that can function as a DPE as well as the range of promoters that use the DPE as a core promoter element. By using an in vitro transcription assay, we identified 17 new DPE-dependent promoters and found that all possessed identical spacing between the Inr and DPE. Moreover, mutational analysis indicated that the insertion or deletion of a single nucleotide between the Inr and DPE causes a reduction in transcriptional activity and TFIID binding. To explore the range of sequences that can function as a DPE, we constructed and analyzed randomized promoter libraries. These experiments yielded the DPE functional range set, which represents sequences that contribute to or are compatible with DPE function. We then analyzed the DPE functional range set in conjunction with a Drosophila core promoter database that we compiled from 205 promoters with accurately mapped start sites. Somewhat surprisingly, the DPE sequence motif is as common as the TATA box in Drosophila promoters. There is, in addition, a striking adherence of Inr sequences to the Inr consensus in DPE-containing promoters relative to DPE-less promoters. Furthermore, statistical and biochemical analyses indicated that a G nucleotide between the Inr and DPE contributes to transcription from DPE-containing promoters. Thus, these data reveal that the DPE exhibits a strict spacing requirement yet some sequence flexibility and appears to be as widely used as the TATA box in Drosophila.


2021 ◽  
Author(s):  
René Dreos ◽  
Nati Malachi ◽  
Anna Sloutskin ◽  
Philipp Bucher ◽  
Tamar Juven-Gershon

AbstractMetazoan core promoters, which direct the initiation of transcription by RNA polymerase II (Pol II), may contain short sequence motifs termed core promoter elements/motifs (e.g. the TATA box, initiator (Inr) and downstream core promoter element (DPE)), which recruit Pol II via the general transcription machinery. The DPE was discovered and extensively characterized in Drosophila, where it is strictly dependent on both the presence of an Inr and the precise spacing from it. Since the Drosophila DPE is recognized by the human transcription machinery, it is most likely that some human promoters contain a downstream element that is similar, though not necessarily identical, to the Drosophila DPE. However, only a couple of human promoters were shown to contain a functional DPE, and attempts to computationally detect human DPE-containing promoters have mostly been unsuccessful. Using a newly-designed motif discovery strategy based on Expectation-Maximization probabilistic partitioning algorithms, we discovered preferred downstream positions (PDP) in human promoters that resemble the Drosophila DPE. Available chromatin accessibility footprints revealed that Drosophila and human Inr+DPE promoter classes are not only highly structured, but also similar to each other, particularly in the proximal downstream region. Clustering of the corresponding sequence motifs using a neighbor-joining algorithm strongly suggests that canonical Inr+DPE promoters could be common to metazoan species. Using reporter assays we demonstrate the contribution of the identified downstream positions to the function of multiple human promoters. Furthermore, we show that alteration of the spacing between the Inr and PDP by two nucleotides results in reduced promoter activity, suggesting a strict spacing dependency of the newly discovered human PDP on the Inr. Taken together, our strategy identified novel functional downstream positions within human core promoters, supporting the existence of DPE-like motifs in human promoters.Author summaryTranscription of genes by the RNA polymerase II enzyme initiates at a genomic region termed the core promoter. The core promoter is a regulatory region that may contain diverse short DNA sequence motifs/elements that confer specific properties to it. Interestingly, core promoter motifs can be located both upstream and downstream of the transcription start site. Variable compositions of core promoter elements have been identified. The initiator (Inr) motif and the downstream core promoter element (DPE) is a combination of elements that has been identified and extensively characterized in fruit flies. Although a few Inr+DPE - containing human promoters have been identified, the presence of transcriptionally important downstream core promoter positions within human promoters has been a matter of controversy in the literature. Here, using a newly-designed motif discovery strategy, we discovered preferred downstream positions in human promoters that resemble fruit fly DPE. Clustering of the corresponding sequence motifs in eight additional species indicated that such promoters could be common to multicellular non-plant organisms. Importantly, functional characterization of the newly discovered preferred downstream positions supports the existence of Inr+DPE-containing promoters in human genes.


2000 ◽  
Vol 74 (5) ◽  
pp. 2459-2465 ◽  
Author(s):  
Pei-Fen Su ◽  
Shu-Yuan Chiang ◽  
Cheng-Wen Wu ◽  
Felicia Y.-H. Wu

ABSTRACT Adeno-associated virus type 2 (AAV) is known to inhibit the promoter activities of several oncogenes and viral genes, including the human papillomavirus type 16 (HPV-16) E6 and E7 transforming genes. However, the target elements of AAV on the long control region (LCR) upstream of E6 and E7 oncogenes are elusive. A chloramphenicol acetyltransferase assay was performed to study the effect of AAV on the transcription activity of the HPV-16 LCR in SiHa (HPV-positive) and C-33A (HPV-negative) cells. The results reveal that (i) AAV inhibited HPV-16 LCR activity in a dose-dependent manner, (ii) AAV-mediated inhibition did not require the HPV gene products, and (iii) the AAV replication gene product Rep78 was involved in the inhibition. Deletion mutation analyses of the HPV-16 LCR showed that regulatory elements outside the core promoter region of the LCR may not be direct targets of AAV-mediated inhibition. Further study with the electrophoretic mobility shift assay demonstrated that Rep78 interfered with the binding of TATA-binding protein (TBP) to the TATA box of the p97 core promoter more significantly than it disrupted the preformed TBP-TATA complex. These data thus suggest that Rep78 may inhibit transcription initiation of the HPV-16 LCR by disrupting the interaction between TBP and the TATA box of the p97 core promoter.


1997 ◽  
Vol 272 (14) ◽  
pp. 9573-9580 ◽  
Author(s):  
Nicolás P. Koritschoner ◽  
José L. Bocco ◽  
Graciela M. Panzetta-Dutari ◽  
Catherine I. Dumur ◽  
Alfredo Flury ◽  
...  

2019 ◽  
Author(s):  
Wei Fang ◽  
Yi Wen ◽  
Xiangyun Wei

AbstractTissue-specific or cell type-specific transcription of protein-coding genes is controlled by both trans-regulatory elements (TREs) and cis-regulatory elements (CREs). However, it is challenging to identify TREs and CREs, which are unknown for most genes. Here, we describe a protocol for identifying two types of transcription-activating CREs—core promoters and enhancers—of zebrafish photoreceptor type-specific genes. This protocol is composed of three phases: bioinformatic prediction, experimental validation, and characterization of the CREs. To better illustrate the principles and logic of this protocol, we exemplify it with the discovery of the core promoter and enhancer of the mpp5b apical polarity gene (also known as ponli), whose red, green, and blue (RGB) cone-specific transcription requires its enhancer, a member of the rainbow enhancer family. While exemplified with an RGB cone-specific gene, this protocol is general and can be used to identify the core promoters and enhancers of other protein-coding genes.


1998 ◽  
Vol 282 (4) ◽  
pp. 731-739 ◽  
Author(s):  
Anne Grove ◽  
Aldo Galeone ◽  
Elaine Yu ◽  
Luciano Mayol ◽  
E.Peter Geiduschek

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