scholarly journals Transcriptional Regulation of the Gene Encoding an Alcohol Dehydrogenase in the Archaeon Sulfolobus solfataricus Involves Multiple Factors and Control Elements

2003 ◽  
Vol 185 (13) ◽  
pp. 3926-3934 ◽  
Author(s):  
Gabriella Fiorentino ◽  
Raffaele Cannio ◽  
Mosè Rossi ◽  
Simonetta Bartolucci
Keyword(s):  
Transcription Factor ◽  
Transcription Factors ◽  
Alcohol Dehydrogenase ◽  
Molecular Mechanisms ◽  
Environmental Changes ◽  
Sulfolobus Solfataricus ◽  
Regulatory Sequences ◽  
Mobility Shift ◽  
Tata Element ◽  
Responsive Element

ABSTRACT A transcriptionally active region has been identified in the 5′ flanking region of the alcohol dehydrogenase gene of the crenarchaeon Sulfolobus solfataricus through the evaluation of the activity of putative transcriptional regulators and the role of the region upstream of the gene under specific metabolic circumstances. Electrophoretic mobility shift assays with crude extracts revealed protein complexes that most likely contain TATA box-associated factors. When the TATA element was deleted from the region, binding sites for both DNA binding proteins, such as the small chromatin structure-modeling Sso7d and Sso10b (Alba), and transcription factors, such as the repressor Lrs14, were revealed. To understand the molecular mechanisms underlying the substrate-induced expression of the adh gene, the promoter was analyzed for the presence of cis-acting elements recognized by specific transcription factors upon exposure of the cell to benzaldehyde. Progressive dissection of the identified promoter region restricted the analysis to a minimal responsive element (PAL) located immediately upstream of the transcription factor B-responsive element-TATA element, resembling typical bacterial regulatory sequences. A benzaldehyde-activated transcription factor (Bald) that specifically binds to the PAL cis-acting element was also identified. This protein was purified from heparin-fractionated extracts of benzaldehyde-induced cells and was shown to have a molecular mass of ∼16 kDa. The correlation between S. solfataricus adh gene activation and benzaldehyde-inducible occupation of a specific DNA sequence in its promoter suggests that a molecular signaling mechanism is responsible for the switch of the aromatic aldehyde metabolism as a response to environmental changes.

Association of SMAD3/4, COUP-Tf, HNF4α, C/EBPα, GATA2 and STAT5 to the Hamp1 Promoter

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 3837-3837
Author(s):  
Pauline Lee ◽  
Jaroslav Truksa ◽  
Ernest Beutler
Keyword(s):  
Transcription Factor ◽  
Transcription Factors ◽  
Nuclear Extract ◽  
Proximal Region ◽  
Proximal Promoter ◽  
Bzip Transcription Factor ◽  
Mobility Shift ◽  
Nuclear Extracts ◽  
Genes Encoding ◽  
Responsive Element

Abstract There are two regions of the murine Hamp1 promoter that have been shown to be critical for Hamp1 expression. The 260 bp proximal region and the distal −1.6 to −1.8 Kb regions appear to be required for responsiveness to IL-6, BMPs and iron. Analyses of 160 bp proximal promoter for consensus transcription factor motifs by MatInspector identified a STAT5 site at the location identified previously by Wrighting et al., Blood 2006, as a functional STAT3 site and by Courselaud et al., J Biol Chem 2002, as a C/EBPα site. Although a SMAD responsive site was not predicted in this region, we (in press), and Verga-Falzacappa et al., J Mol Med 2008, have demonstrated that there is a functional BMP responsive element (GGCGCC) in this region. A probe encompassing the putative BMP-RE1, STAT, C/EBPα, and AP1 motifs were used in electrophoretic mobility shift assays (EMSA). We found that the addition of cold competitor DNA corresponding to STAT3, C/EBPα and AP1 consensus motifs did not block the binding of transcription factors from liver nuclear extracts to the BMP-RE1/STAT/C/EBPα/AP1 probe. In contrast, the addition of cold competitor DNA corresponding the SMAD3/4 or STAT5 completely blocked essentially all binding of liver nuclear transcription factors to the BMP-RE1/STAT/C/EBPα/AP1 probe. Analyses of the −161 to −260 bp proximal promoter for consensus transcription factor motifs identified a GATA2 binding site and a SMAD responsive site (TGTCTGCCC). Two long probes encompassing the to −161 to −260 bp region were used in EMSAs. Binding of liver nuclear extracts to a probe encompassing the GATA motif was blocked by the addition of a GATA consensus DNA. Similarly, binding to a long probe encompassing the SMAD responsive site was blocked by the addition of a SMAD3/4 consensus DNA. Analyses of the 1.6 to 1.7 Kb region of the distal murine Hamp1 promoter identified several transcription factor motifs: bZIP transcription factor that acts on nuclear genes encoding mitochondrial proteins, COUP-Tf/HNF4α, and MEL1 (MDS1/EVI1-like gene1) to be both in human and mouse Hamp genes. Although a SMAD responsive site was not identified in this region, we have demonstrated that there is a functional BMP responsive element (GGCGCC) in this region. Using EMSA with probes corresponding to the −1.6 to −1.7 bp region of the hepcidin promoter, we examined the binding of transcription factors from liver nuclear extracts derived from mice. Binding of liver nuclear extract to a probe corresponding to the BMP-RE2, bZIP, HNF4α, COUP motifs was blocked by cold competitor probes corresponding to SMAD3/4, HNF4α, COUP-Tf, and Stat5. Whereas competitor probes to Smad3/4 and HNF4α competed for the binding of specific bands to the radiolabelled probe, total binding was blocked with cold competitor probes to the consensus COUP-Tf and Stat5 motifs. Supershift analyses using antibodies to HNF4α, COUP, SMAD4 demonstrated the binding of these transcription factors to the radiolabeled BMP-RE2/bZIP/HNF4α/COUP probe. Binding to a probe encompassing a MEL motif was blocked by the addition of cold competitor to C/EBPα and could be supershifted with antibodies against C/EBPα. In conclusion, SMAD 3/4, COUP-Tf, HNF4α, C/EBPα, GATA2 and STAT5 appear to be important in the regulation of Hamp1 expression.

C-MYB and C/EBP Family Transcription Factors Regulate the Gfi-1 Promoter.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 4214-4214
Author(s):  
Richard Dahl ◽  
Kristin S. Owens
Keyword(s):  
Transcription Factor ◽  
Transcription Factors ◽  
Chromatin Immunoprecipitation ◽  
Binding Sites ◽  
Myeloid Cells ◽  
Transient Transfection ◽  
Mobility Shift ◽  
Reporter Assays ◽  
Immature Myeloid Cells ◽  
Factor C

Abstract Gfi-1 −/− mice generate abnormal immature myeloid cells exhibiting characteristics of both monocytes and granulocytes. One of Gfi-1’s critical functions is to downregulate monocyte specific genes in order for granulocytes to develop properly. Since the transcription factors C/EBP alpha and C/EBP epsilon are needed for granulocyte development we hypothesized that these factors may regulate Gfi-1 expression. The Gfi-1 promoter contains several putative C/EBP binding sites and we show by electrophoretic mobility shift and chromatin immunoprecipitation that C/EBP family members can bind to some of these sites. However we were unable to see activation of the Gfi-1 promoter by C/EBP proteins in transient transfection reporter assays. Other groups have shown that C/EBP proteins can synergize with the transcription factor c-myb. We observed that the Gfi-1 promoter contains sites for the hematopoietic transcription factor c-myb. Sevral of these c-myb binding sites are adjacent to C/EBP binding sites. In reporter assays in non-hematopoietic cells c-myb activated the Gfi-1 promoter by itself and this activity was enhanced when we included either C/EBP alpha or epsilon in the transfection. Our data suggests that C/EBP proteins and c-myb regulate the transcription of Gfi-1 in myeloid cells.

scholarly journals Heterologous Expression of Transcription Factor AtWRKY57 Alleviates Salt Stress-Induced Oxidative Damage

2018 ◽  
Vol 12 (1) ◽  
pp. 204-218
Author(s):  
Wei Tang
Keyword(s):  
Transcription Factor ◽  
Transcription Factors ◽  
Salt Stress ◽  
Heterologous Expression ◽  
Stress Tolerance ◽  
Molecular Mechanisms ◽  
Abiotic Stress Tolerance ◽  
Thiobarbituric Acid Reactive Substance ◽  
Salt Stress Tolerance ◽  
Wrky Transcription Factors

Background:WRKY transcription factors play important roles in the responses to abiotic stresses, seed dormancy, seed germination, developmental processes, secondary metabolism, and senescence in plants. However, molecular mechanisms of WRKY transcription factors-related abiotic stress tolerance have not been fully understood.Methods:In this investigation, transcription factor AtWRKY57 was introduced into cell lines of rice (Oryza sativaL.), tobacco (Nicotiana tabacum), and white pine (Pinus strobesL.) for characterization of its function in salt stress tolerance. The purpose of this investigation is to examine the function of AtWRKY in a broad sample of plant species including monocotyledons, dicotyledons, and gymnosperms.Results:The experimental results demonstrated that heterologous expression of transcription factor AtWRKY57 improves salt stress tolerance by decreasing Thiobarbituric Acid Reactive Substance (TBARS), increasing Ascorbate Peroxidase (APOX) and Catalase (CAT) activity under salt stress. In rice, overexpression of transcription factor AtWRKY57 enhances expression of Ca2+-dependent protein kinase genesOsCPk6andOsCPk19to counteract salt stress.Conclusion:These results indicated that transcription factor AtWRKY57 might have practical application in genetic engineering of plant salt tolerance throughout the plant kingdom.

scholarly journals Nr4a2 Transcription Factor in Hippocampal Synaptic Plasticity, Memory and Cognitive Dysfunction: A Perspective Review

2021 ◽  
Vol 14 ◽  
Author(s):  
Judit Català-Solsona ◽  
Alfredo J. Miñano-Molina ◽  
José Rodríguez-Álvarez
Keyword(s):  
Transcription Factor ◽  
Transcription Factors ◽  
Synaptic Plasticity ◽  
Nuclear Receptor ◽  
Molecular Mechanisms ◽  
Expression Profiles ◽  
Gene Expression Profiles ◽  
Memory Formation ◽  
Synaptic Dysfunction ◽  
Hippocampal Synaptic Plasticity

Long-lasting changes of synaptic efficacy are largely mediated by activity-induced gene transcription and are essential for neuronal plasticity and memory. In this scenario, transcription factors have emerged as pivotal players underlying synaptic plasticity and the modification of neural networks required for memory formation and consolidation. Hippocampal synaptic dysfunction is widely accepted to underlie the cognitive decline observed in some neurodegenerative disorders including Alzheimer’s disease. Therefore, understanding the molecular pathways regulating gene expression profiles may help to identify new synaptic therapeutic targets. The nuclear receptor 4A subfamily (Nr4a) of transcription factors has been involved in a variety of physiological processes within the hippocampus, ranging from inflammation to neuroprotection. Recent studies have also pointed out a role for the activity-dependent nuclear receptor subfamily 4, group A, member 2 (Nr4a2/Nurr1) in hippocampal synaptic plasticity and cognitive functions, although the underlying molecular mechanisms are still poorly understood. In this review, we highlight the specific effects of Nr4a2 in hippocampal synaptic plasticity and memory formation and we discuss whether the dysregulation of this transcription factor could contribute to hippocampal synaptic dysfunction, altogether suggesting the possibility that Nr4a2 may emerge as a novel synaptic therapeutic target in brain pathologies associated to cognitive dysfunctions.

scholarly journals The biological characteristics of transcription factors AP-2α and AP-2γ and their importance in various types of cancers

2019 ◽  
Vol 39 (3) ◽  
Author(s):  
Damian Kołat ◽  
Żaneta Kałuzińska ◽  
Andrzej K. Bednarek ◽  
Elżbieta Płuciennik
Keyword(s):  
Gene Expression ◽  
Transcription Factor ◽  
Transcription Factors ◽  
Molecular Mechanisms ◽  
Regulation Of Gene Expression ◽  
Cancer Tissue ◽  
Diagnostic Biomarkers ◽  
Oncological Patients ◽  
Wide Range ◽  
Non Coding Rnas

Abstract The Activator Protein 2 (AP-2) transcription factor (TF) family is vital for the regulation of gene expression during early development as well as carcinogenesis process. The review focusses on the AP-2α and AP-2γ proteins and their dualistic regulation of gene expression in the process of carcinogenesis. Both AP-2α and AP-2γ influence a wide range of physiological or pathological processes by regulating different pathways and interacting with diverse molecules, i.e. other proteins, long non-coding RNAs (lncRNA) or miRNAs. This review summarizes the newest information about the biology of two, AP-2α and AP-2γ, TFs in the carcinogenesis process. We emphasize that these two proteins could have either oncogenic or suppressive characteristics depending on the type of cancer tissue or their interaction with specific molecules. They have also been found to contribute to resistance and sensitivity to chemotherapy in oncological patients. A better understanding of molecular network of AP-2 factors and other molecules may clarify the atypical molecular mechanisms occurring during carcinogenesis, and may assist in the recognition of new diagnostic biomarkers.

A nuclease-hypersensitive element of the human c-myc promoter interacts with a transcription initiation factor

1989 ◽  
Vol 9 (11) ◽  
pp. 5123-5133
Author(s):  
E H Postel ◽  
S E Mango ◽  
S J Flint
Keyword(s):  
Transcription Factor ◽  
Transcription Initiation ◽  
Molecular Mechanisms ◽  
Initiation Factor ◽  
Mobility Shift ◽  
Cis Acting ◽  
Factor Binding ◽  
Myc Oncogene ◽  
Transcription In Vitro

Transcription of the human c-myc oncogene is elaborately regulated, but the relevant molecular mechanisms are not yet understood. To begin to define elements and enzyme systems responsible for c-myc transcription in vitro, we partially purified a transcription factor essential for efficient and accurate in vitro initiation from the principal myc promoter, P2. DNA mobility shift assays located the factor binding domain at -142 to -115 with respect to the P1 promoter. This region contains pur/pyr sequences (predominantly purines in one strand), nuclease-hypersensitive sites (U. Siebenlist, L. Henninghausen, J. Battey, and P. Leder, Cell 37:381-391, 1984; C. Boles and M. Hogan, Biochemistry 26:367-376, 1987), and a triple-helix-forming element (M. Cooney, G. Czernuszewicz, E. Postel, S. Flint, and M. Hogan, Science 241:456-459, 1988). Methylation interference mapping established that the factor, termed PuF, directly contacts the repeated palindromic sequence GGGTGGG of the -142/-115 element. The interaction of PuF with this cis-acting element is necessary for P2 transcription in vitro, for (i) deletion of this 5' region from the myc promoter greatly reduced transcription efficiency and (ii) a synthetic duplex oligonucleotide corresponding to the -142/-115 sequence completely repressed c-myc transcription in the presence of the partially purified factor. These observations lend support to the hypothesis that pur/pyr sequences perform important biological roles in the regulation of c-myc gene expression, most likely by serving as transcription factor binding sites.

Analysis of transcription factors binding to the human 7SL RNA gene promoter

1999 ◽  
Vol 77 (5) ◽  
pp. 431-438 ◽  
Author(s):  
Jürgen Müller ◽  
Bernd-Joachim Benecke
Keyword(s):  
Transcription Factor ◽  
Transcription Factors ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Rna Polymerase Iii ◽  
Gene Promoter ◽  
7Sl Rna ◽  
Polymerase Iii ◽  
Responsive Element

Transcription of the human 7SL RNA gene by RNA polymerase III depends on the concerted action of transcription factors binding to the gene-internal and gene-external parts of its promoter. Here, we investigated which transcription factors interact with the human 7SL RNA gene promoter and which are required for transcription of the human 7SL RNA gene. A-box/B-box elements were previously identified in 5S RNA, tRNA, and virus associated RNA genes and are recognized by transcription factor IIIC (TFIIIC). The gene-internal promoter region of the human 7SL RNA gene shows only limited similarity to those elements. Nevertheless, competition experiments and the use of highly enriched factor preparations demonstrate that TFIIIC is required for human 7SL transcription. The gene-external part of the promoter includes an authentic cAMP-responsive element previously identified in various RNA polymerase II promoters. Here we demonstrate that members of the activating transcription factor/cyclic AMP-responsive element binding protein (ATF/CREB) transcription factor family bind specifically to this element in vitro. However, the human 7SL RNA gene is not regulated by cAMP in vivo. Furthermore, in vitro transcription of the gene does not depend on ATF/CREB transcription factors. It rather appears that a transcription factor with DNA-binding characteristics like ATF/CREB proteins but otherwise different properties is required for human 7SL RNA transcription.Key words: 7SL RNA, ATF, CRE, TFIIIC, RNA polymerase III.

scholarly journals Interdependent transcription control elements regulate the expression of the SPRR2A gene during keratinocyte terminal differentiation.

1996 ◽  
Vol 16 (10) ◽  
pp. 5365-5374 ◽  
Author(s):  
D F Fischer ◽  
S Gibbs ◽  
P van De Putte ◽  
C Backendorf
Keyword(s):  
Transcription Factors ◽  
Molecular Mechanisms ◽  
Terminal Differentiation ◽  
Site Directed Mutagenesis ◽  
Deletion Mapping ◽  
Transcription Control ◽  
Mobility Shift ◽  
Response Element

Expression of the SPRR2A gene, a member of the small proline-rich family of cornified cell envelope precursor proteins, is strictly linked to keratinocyte terminal differentiation both in vivo and in vitro. In this study, we explored the molecular mechanisms underlying this regulation in transiently transfected primary keratinocytes induced to differentiate in vitro. Deletion mapping and site-directed mutagenesis of SPRR2A promoter-chloramphenicol acetyltransferase constructs indicate that four transcription control elements are essential and sufficient for promoter activity. These elements were further characterized by electrophoretic mobility shift and identified as (i) an inverted octamer doublet, bound by the POU domain factor Oct-11 (Skn-1a/i, Epoc-1), (ii) an interferon-stimulated response element recognized by interferon regulatory factors 1 and 2, (iii) an Ets binding site partially overlapping the interferon-stimulated response element, and (iv) a TG box recognized by the Sp1 family of zinc finger transcription factors. Destruction of a single terminal differentiation element is sufficient to completely abolish transcription from the SPRR2A promoter, indicating that these transcription control elements function in concert in an interdependent manner. Apparently, integration of signals transmitted by the above-mentioned transcription factors is necessary and sufficient to promote gene expression during keratinocyte terminal differentiation.

scholarly journals Differential Requirement of the Transcription Factor Mcm1 for Activation of the Candida albicans Multidrug Efflux PumpMDR1by Its Regulators Mrr1 and Cap1

2011 ◽  
Vol 55 (5) ◽  
pp. 2061-2066 ◽  
Author(s):  
Selene Mogavero ◽  
Arianna Tavanti ◽  
Sonia Senesi ◽  
P. David Rogers ◽  
Joachim Morschhäuser
Keyword(s):  
Transcription Factor ◽  
Candida Albicans ◽  
Transcription Factors ◽  
Molecular Mechanisms ◽  
Efflux Pump ◽  
Multidrug Efflux ◽  
Multidrug Efflux Pump ◽  
Gain Of Function ◽  
Pathogenic Yeast ◽  
Content Type

ABSTRACTOverexpression of the multidrug efflux pump Mdr1 causes increased fluconazole resistance in the pathogenic yeastCandida albicans. The transcription factors Mrr1 and Cap1 mediateMDR1upregulation in response to inducing stimuli, and gain-of-function mutations in Mrr1 or Cap1, which render the transcription factors hyperactive, result in constitutiveMDR1overexpression. The essential MADS box transcription factor Mcm1 also binds to theMDR1promoter, but its role in inducible or constitutiveMDR1upregulation is unknown. Using a conditional mutant in which Mcm1 can be depleted from the cells, we investigated the importance of Mcm1 forMDR1expression. We found that Mcm1 was dispensable forMDR1upregulation by H2O2but was required for fullMDR1induction by benomyl. A C-terminally truncated, hyperactive Cap1 could upregulateMDR1expression both in the presence and in the absence of Mcm1. In contrast, a hyperactive Mrr1 containing a gain-of-function mutation depended on Mcm1 to causeMDR1overexpression. These results demonstrate a differential requirement for the coregulator Mcm1 for Cap1- and Mrr1-mediatedMDR1upregulation. When activated by oxidative stress or a gain-of-function mutation, Cap1 can induceMDR1expression independently of Mcm1, whereas Mrr1 requires either Mcm1 or an active Cap1 to cause overexpression of theMDR1efflux pump. Our findings provide more detailed insight into the molecular mechanisms of drug resistance in this important human fungal pathogen.

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