Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P51532 (transcriptional activator)
 6,546 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The full-length cDNA for a transcriptional activator, DBP, that binds to the D site of the albumin promoter has been cloned. DBP belongs to a family of related transcription factors including Fos, Jun, CREB, and C/EBP, which share a conserved basic domain. However, unlike most other members of this family, DBP does not contain a "leucine zipper" structure. Among several rat tissues tested, significant levels of its protein are only observed in liver; yet, with the exception of testis, DBP mRNA is present in all of the examined tissues. DBP as well as its mRNA accumulate to significant levels only in adult animals. During chemically induced liver regeneration, DBP expression is rapidly down-regulated, suggesting that DBP may be involved in the proliferation control of hepatocytes. This cell growth-dependent expression of DBP, in contrast to its tissue specificity, appears to be controlled at the level of mRNA accumulation.
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PMID:DBP, a liver-enriched transcriptional activator, is expressed late in ontogeny and its tissue specificity is determined posttranscriptionally. 204 17

In order to examine whether splicing can occur cotranscriptionally in mammalian nuclei, we mapped exon-intron boundaries on nascent RNA chains transcribed by RNA polymerase II. A procedure that allows fractionation of nuclei into a chromatin pellet containing DNA, histones, and ternary transcription complexes and a supernatant containing the bulk of the nonhistone proteins and RNAs that are released from their DNA templates was developed. The transcripts of the genes encoding DBP, a transcriptional activator protein, and HMG coenzyme A reductase recovered from the chromatin pellet and the supernatant were analyzed by S1 nuclease mapping. The large majority of the RNA molecules from the pellet appeared to be nascent transcripts, since, in contrast to the transcripts present in the supernatant, they were not cleaved at the polyadenylation site but rather contained heterogeneous 3' termini encompassing this site. Splicing intermediates could be detected among nascent and released transcripts, suggesting that splicing occurs both cotranscriptionally and posttranscriptionally. Our results also indicate that polyadenylation is not required for the splicing of the last DBP intron. In addition to allowing detailed structural analysis of nascent RNA chains, the physical isolation of nascent transcripts also yields reliable measurements of relative transcription rates.
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PMID:Physical isolation of nascent RNA chains transcribed by RNA polymerase II: evidence for cotranscriptional splicing. 752 61

The roles of interferons (IFNs) in apoptosis are not fully understood. In this study we show that in the U937 monoblastic leukemia cell line, pretreatment with IFN-gamma enhanced sensitivity to apoptosis triggered by gamma-irradiation or antitumor agents (etoposide or adriamycin), as well as by anti-Fas antibody. In addition, IFN-gamma caused an increased expression of the interleukin-1 beta-converting enzyme (Ice) gene, following strong induction of the interferon regulatory factor-1 (IRF-1) gene, the product of which is a transcriptional activator of the Ice gene. An inhibitor of ICE/Ced-3 family proteases, Z-Asp-CH2-DCB, blocked apoptosis in control cells as well as in IFN-gamma-pretreated cells. These results suggest that enhanced susceptibility of IFN-gamma-pretreated cells to apoptosis is mediated through the induction of Ice by IRF-1. This pathway is not affected by interleukin-1 beta (IL-1 beta) since neutralizing antibody against IL-1 beta failed to suppress the IFN-gamma-mediated enhancement of cell death, and IL-1 beta itself did not mimic the effect of IFN-gamma.
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PMID:Interferon-gamma induces Ice gene expression and enhances cellular susceptibility to apoptosis in the U937 leukemia cell line. 895 78

DBP, HLF and TEF comprise a distinct subfamily of mammalian bZIP proteins that plays an important role in regulation of tissue-specific gene expression, particularly in the liver. In this report we demonstrate that DBP contains a 38 amino acid TAD which is highly homologous to the HLF and TEF TADs that we have delineated previously. Deletion of this domain completely abrogates transcriptional activity of native DBP and GAL4-DBP fusion proteins. This domain functions as a modular TAD that is a potent transcriptional activator when fused to the GAL4 DBD. While DBP itself is a liver-specific transactivator, the DBP TAD is active in a variety of cell types, indicating that liver-specific activity is not an intrinsic property of the TAD and must be conferred by other regions of the protein. Using GAL4-HLF fusion proteins, we further refine the core TAD of PAR proteins to a region of 13 amino acids. Recently described PAR-bZIP proteins from Drosophila and zebrafish also contain domains that share strong homology with the TAD of mammalian PAR proteins, making this one of the most highly evolutionarily conserved TADs identified to date.
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PMID:The DBP transcriptional activation domain is highly homologous to that of HLF and TEF and is not responsible for the tissue type-specific transcriptional activity of DBP. 1122 63

Baculoviruses elicit the formation of a nuclear domain, called the virogenic stroma, in which viral DNA replication and nucleocapsid assembly occur. We had previously reported that nuclear focus formation of a transcriptional activator, IE1, is triggered by its binding to a viral DNA element, hr, and predicted that this hr-induced IE1 focus is an initial scaffold for the virogenic stroma. However, LEF3, a component of the virogenic stroma, did not localize to the IE1 foci. In exploring a mediator for its localization, we found that a baculovirus DNA helicase (P143), in combination with IE1 and hr, induced a subnuclear structure to which LEF3 localized and also that another component of the virogenic stroma, DBP, is able to localize to this structure. These results reveal that only four viral molecules are necessary to establish a nuclear domain which possesses a recruiting ability for a component of the virogenic stroma.
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PMID:Induction of a subnuclear structure by the simultaneous expression of baculovirus proteins, IE1, LEF3, and P143 in the presence of hr. 1678 Sep 15