Search results for "nuclear factor"

showing 10 items of 84 documents

Species-specific mechanisms for cholesterol 7alpha-hydroxylase (CYP7A1) regulation by drugs and bile acids.

2005

The gene encoding cholesterol 7alpha-hydroxylase (CYP7A1) is tightly regulated in order to control intrahepatic cholesterol and bile acid levels. Ligands of the xenobiotic-sensing pregnane X receptor inhibit CYP7A1 expression. To retrace the evolution of the molecular mechanisms underlying CYP7A1 inhibition, we used a chicken hepatoma cell system that retains the ability to be induced by phenobarbital and other drugs. Whereas bile acids regulate CYP7A1 via small heterodimer partner and liver receptor homolog-1, mRNA expression of these nuclear receptors is unchanged by xenobiotics. Instead, drugs repress chicken hepatic nuclear factor 4alpha (HNF4alpha) transcript levels concomitant with a …

Receptors Steroidmedicine.drug_classMolecular Sequence DataBiophysicsReceptors Cytoplasmic and NuclearBiologyIn Vitro TechniquesCholesterol 7 alpha-hydroxylaseBiochemistryGene Expression Regulation EnzymologicBile Acids and SaltsMiceSpecies SpecificitymedicineAnimalsHumansRNA MessengerCholesterol 7-alpha-HydroxylaseMolecular BiologyCells CulturedMice KnockoutPregnane X receptorBile acidLiver receptor homolog-1Pregnane X ReceptorPhosphoproteinsRecombinant ProteinsDNA-Binding ProteinsBiochemistryNuclear receptorHepatocyte Nuclear Factor 4PhenobarbitalSmall heterodimer partnerHepatocytesFarnesoid X receptorSignal transductionChickensSignal TransductionTranscription FactorsArchives of biochemistry and biophysics
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The peroxisome proliferator response element (PPRE) present at positions -681/-669 in the rat liver 3-ketoacyl-CoA thiolase B gene functionally inter…

2000

Although previous data showed that the putative thiolase B PPRE located at -681/-669 bind the PPARalpha-RXRalpha heterodimer in vitro (Kliewer et al. (1992) Nature 358, 771-774), there is no evidence about the functional role of this element. By gel mobility-shift assay, we found an interaction of this PPRE with not only PPARalpha but also with HNF-4. By transfection of cells with the putative PPRE-driven luciferase reporter vector and PPARalpha, we found no significant activation of the luciferase gene expression, in contrast to the case with reporter expression driven by the PPRE of the peroxisomal bifunctional enzyme. On the other hand, HNF-4 activated the luciferase gene expression driv…

Response elementBiophysicsReceptors Cytoplasmic and NuclearBiologyTransfectionBiochemistryDNA-binding proteinPeroxisomal Bifunctional EnzymeGenes ReporterGene expressionAnimalsMolecular BiologyGeneDNA PrimersBase SequenceThiolaseCell BiologyTransfectionDNAAcetyl-CoA C-AcyltransferasePhosphoproteinsMolecular biologyRatsDNA-Binding ProteinsHepatocyte nuclear factor 4Hepatocyte Nuclear Factor 4LiverCOS CellsPeroxisome ProliferatorsTranscription FactorsBiochemical and biophysical research communications
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IFN-gamma-induced protein 10 is a novel biomarker of rhinovirus-induced asthma exacerbations

2007

BACKGROUND: Rhinovirus-induced acute asthma is the most frequent trigger for asthma exacerbations. OBJECTIVE: We assessed which inflammatory mediators were released from bronchial epithelial cells (BECs) after infection with rhinovirus and then determined whether they were also present in subjects with acute virus-induced asthma, with the aim to identify a biomarker or biomarkers for acute virus-induced asthma. METHODS: BECs were obtained from bronchial brushings of steroid-naive asthmatic subjects and healthy nonatopic control subjects. Cells were infected with rhinovirus 16. Inflammatory mediators were measured by means of flow cytometry with a cytometric bead array. Subjects with acute a…

RhinovirusExacerbationNF-κB Nuclear factor κBAnti-Inflammatory Agentsairway inflammationmedicine.disease_causeDexamethasoneImmunology and AllergyChemokine CCL5LungRV-16 Rhinovirus 16Cells CulturedLR Likelihood ratioRespiratory diseaseMiddle AgedFlow Cytometrymedicine.anatomical_structureBiomarker (medicine)medicine.symptomRhinovirusChemokines CXCmedicine.drugAdultAdolescentImmunologyInflammationIFN gammaArticlemedicineHumansDexamethasoneAgedAsthmaPicornaviridae InfectionsInterleukin-6Tumor Necrosis Factor-alphabusiness.industryInterleukin-8BEC Bronchial epithelial cellEpithelial CellsTCID50 Tissue culture infectious dose 50%medicine.diseaseAsthmarespiratory tract diseasesChemokine CXCL10ImmunologyIP-10 IFN-γ–induced protein 10businessBiomarkersRespiratory tract
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Glucocorticoid receptor regulates organic cation transporter 1 (OCT1, SLC22A1) expression via HNF4α upregulation in primary human hepatocytes

2013

Abstract Background Organic cation transporter 1 (OCT1, SLC22A1) is a membrane transporter that is important for therapeutic effect of the antidiabetic drug metformin. Its liver-specific expression in hepatocytes is strongly controlled by hepatocyte nuclear factor-4α (HNF4α). HNF4α expression and transcriptional activity have been demonstrated to be augmented by glucocorticoid receptor (GR) in human hepatocytes and rodent livers. Methods It was examined whether GR activation indirectly induces OCT1 gene expression via HNF4α up-regulation in primary human hepatocytes.We also examined which other transcription factors are involved in OCT1 gene expression and whether they are regulated by dexa…

Time FactorsPrimary Cell CultureTransfectionDexamethasoneReceptors GlucocorticoidGlucocorticoid receptorTransduction GeneticEnhancer bindingCoactivatorGene expressionHumansRNA MessengerGlucocorticoidsTranscription factorPharmacologyRegulation of gene expressionChemistryCCAAT-Enhancer-Binding Protein-betaOrganic Cation Transporter 1Hep G2 CellsGeneral MedicineTransfectionPeroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alphaMolecular biologyUp-RegulationHepatocyte Nuclear Factor 4Cell cultureHepatocytesTranscription FactorsPharmacological Reports
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The stable repression of mesenchymal program is required for hepatocyte identity: A novel role for hepatocyte nuclear factor 4α

2011

The concept that cellular terminal differentiation is stably maintained once development is complete has been questioned by numerous observations showing that differentiated epithelium may undergo an epithelial-to-mesenchymal transition (EMT) program. EMT and the reverse process, mesenchymal-to-epithelial transition (MET), are typical events of development, tissue repair, and tumor progression. In this study, we aimed to clarify the molecular mechanisms underlying these phenotypic conversions in hepatocytes. Hepatocyte nuclear factor 4α (HNF4α) was overexpressed in different hepatocyte cell lines and the resulting gene expression profile was determined by real-time quantitative polymerase…

Transcription FactorCellular differentiationMESH: Mice KnockoutMESH: HepatocytesMesodermMice0302 clinical medicineMESH: Liver NeoplasmsMESH: AnimalsHepatocyteHepatocyte Nuclear Factor 1-alphaMESH: Carcinoma HepatocellularRegulator geneHepatocyte differentiationMice KnockoutMESH: Mesoderm0303 health sciencesLiver NeoplasmsCell DifferentiationMESH: Transcription FactorsCell biologyHepatocyte nuclear factorsPhenotypeMESH: Models AnimalHepatocyte Nuclear Factor 4MESH: Epithelial CellsLiver Neoplasm030220 oncology & carcinogenesisModels AnimalMESH: Hepatocyte Nuclear Factor 4HumanMESH: Cell DifferentiationMESH: Cell Line TumorCarcinoma Hepatocellular[SDV.BC]Life Sciences [q-bio]/Cellular BiologyBiologyMESH: PhenotypeArticle03 medical and health scienceshepatocyte; mesenchymal program; SnailCell Line TumorAnimalsHumansMESH: Hepatocyte Nuclear Factor 1-alphaMESH: MiceTranscription factorAnimals; Carcinoma Hepatocellular; Cell Differentiation; Cell Line Tumor; Epithelial Cells; Hepatocyte Nuclear Factor 1-alpha; Hepatocyte Nuclear Factor 4; Hepatocytes; Humans; Liver Neoplasms; Mesoderm; Mice; Mice Knockout; Models Animal; Phenotype; Snail Family Transcription Factors; Transcription Factors; Hepatology030304 developmental biologyEpithelial CellMESH: HumansHepatologyAnimalMesenchymal stem cellEpithelial CellsSnail Family Transcription FactorMolecular biologyHepatocyte nuclear factor 4HepatocytesSnail Family Transcription FactorsChromatin immunoprecipitationTranscription Factors
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Characterization and DNA-binding properties of GRF, a novel monomeric binding orphan receptor related to GCNF and betaFTZ-F1

1999

0014-2956 (Print) Comparative Study Journal Article Research Support, Non-U.S. Gov't; A PCR approach has been used to isolate, from Bombyx mori, a cDNA encoding a novel orphan receptor (GRF) that is most closely related to Bombyx betaFTZ-F1 and to the vertebrate germ cell nuclear factor. The major GRF mRNA is detected in most tissues as an 8-kb transcript whose amount follows the circulating ecdysteroid concentration with a delay. The expression pattern of GRF is similar to that of the Bombyx homologue of the Drosophila early-late gene DHR3, and precedes that of betaFTZ-F1 in all stages and tissues examined. The GRF protein is thus likely to be required in many tissues, but in a temporally …

Transcription GeneticReceptors Cytoplasmic and NuclearFushi Tarazu Transcription FactorsSequence HomologyGenes InsectDevelopmental/drug effectsSteroidogenic Factor 1BiochemistryBombyx/*chemistry/growth & developmentDNA/*metabolismNuclear Receptor Subfamily 6 Group A Member 1ReceptorsCloning MolecularReceptorRegulation of gene expressionOrphan receptorbiologyGene Expression Regulation DevelopmentalDNA-Binding ProteinsEcdysterone/pharmacologyAmino AcidEcdysteroneInsect Proteins/genetics/*isolation & purification/metabolismInsect ProteinsRecombinant Fusion Proteins/metabolismTranscriptionProtein StructureRecombinant Fusion ProteinsGerm cell nuclear factorMolecular Sequence DataGeneticComplementary DNAAnimalsAmino Acid SequenceBinding siteBombyxHomeodomain ProteinsBinding Sitespurification/metabolismSequence Homology Amino AcidBase SequencefungiMolecularCytoplasmic and Nuclear/chemistryDNABombyxbiology.organism_classificationMolecular biologyProtein Structure TertiaryTranscription Factors/chemistry/genetics/*isolation &Nuclear receptorGene Expression RegulationGenesDNA-Binding Proteins/chemistry/genetics/*isolation &InsectSequence AlignmentTertiaryTranscription FactorsCloning
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An epistatic mini-circuitry between the transcription factors Snail and HNF4α controls liver stem cell and hepatocyte features exhorting opposite reg…

2011

Preservation of the epithelial state involves the stable repression of epithelial-to-mesenchymal transition program, whereas maintenance of the stem compartment requires the inhibition of differentiation processes. A simple and direct molecular mini-circuitry between master elements of these biological processes might provide the best device to keep balanced such complex phenomena. In this work, we show that in hepatic stem cell Snail, a transcriptional repressor of the hepatocyte differentiation master gene HNF4α, directly represses the expression of the epithelial microRNAs (miRs)-200c and-34a, which in turn target several stem cell genes. Notably, in differentiated hepatocytes HNF4α, p…

Transcription GeneticTranscription FactorCellular differentiationLiver Stem CellSnailMESH: Mice KnockoutMESH: HepatocytesMice0302 clinical medicineSnail; hnf4a; mir-200; mir-34a; stemness; hepatocyte differentiationHepatocyteMESH: AnimalsMice KnockoutHepatocyte differentiationmir-34a0303 health sciencesStemneStem CellsMicroRNACell DifferentiationMESH: Transcription FactorsCell biologySnailmir-200Hepatocyte Nuclear Factor 4Liver030220 oncology & carcinogenesisMiRs-200MESH: Hepatocyte Nuclear Factor 4Hepatocyte differentiation; HNF4a; MiR-34a; MiRs-200; Snail; Stemness; Animals; Cell Differentiation; Epithelial-Mesenchymal Transition; Hepatocyte Nuclear Factor 4; Hepatocytes; Liver; Mice; Mice Knockout; MicroRNAs; Snail Family Transcription Factors; Stem Cells; Transcription Factors; Transcription Genetic; Cell Biology; Molecular BiologyStem cellhnf4aMESH: Cell Differentiationhepatocyte differentiationEpithelial-Mesenchymal TransitionMESH: Stem Cells[SDV.BC]Life Sciences [q-bio]/Cellular BiologyBiologystemness03 medical and health sciencesStem Cellbiology.animalAnimals[SDV.BBM]Life Sciences [q-bio]/Biochemistry Molecular BiologyEpithelial–mesenchymal transitionMESH: MiceMolecular BiologyTranscription factor030304 developmental biologyOriginal PaperAnimalMESH: Transcription GeneticSnail Family Transcription FactorCell BiologyMolecular biologyMicroRNAsMESH: Epithelial-Mesenchymal TransitionHepatocyte nuclear factor 4HepatocytesSnail Family Transcription FactorsMESH: MicroRNAsMESH: LiverTranscription FactorsCell Death & Differentiation
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Role of hepatocyte nuclear factor 3γ in the expression of human CYP2C genes

2004

Hepatocyte nuclear factor 3 gamma (HNF-3 gamma) is an important transcription factor for the maintenance of specific liver functions. However, its relevance in the expression of human cytochrome P450 (CYP) genes has not yet been explored. Several HNF3 putative binding sites can be identified in human CYP2C 5'-flanking regions. Gene reporter experiments with proximal promoters revealed that HNF-3 gamma transactivated CYP2C8, CYP2C9, and CYP2C19 (25-, 4-, and 4-fold, respectively), but it did not transactivate CYP2C18. However, overexpression of HNF-3 gamma in hepatoma cells by means of a recombinant adenovirus induced CYP2C9, CYP2C18, and CYP2C19 mRNA (4.5-, 20-, and 50-fold, respectively) b…

Transcriptional ActivationRecombinant Fusion ProteinsGenetic VectorsBiophysicsBiologyHydroxamic AcidsTransfectionBiochemistryGene Expression Regulation EnzymologicAdenoviridaeCytochrome P-450 Enzyme SystemSp3 transcription factorCell Line TumormedicineHumansRNA MessengerEnzyme InhibitorsLuciferasesPromoter Regions GeneticMolecular BiologyTranscription factorBinding SitesNuclear ProteinsPromoterMolecular biologyDNA-Binding ProteinsHistone Deacetylase InhibitorsHepatocyte nuclear factorsTrichostatin AHepatocyte nuclear factor 4Hepatocyte nuclear factor 4 alphaHepatocytesFOXA2Transcription Initiation SiteHepatocyte Nuclear Factor 3-gammaHeLa CellsTranscription Factorsmedicine.drugArchives of Biochemistry and Biophysics
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TGFβ-induced EMT requires focal adhesion kinase (FAK) signaling

2007

The epithelial-to-mesenchymal transition (EMT) is a crucial process, occurring both during development and tumor progression, by which an epithelial cell undergoes a conversion to a mesenchymal phenotype, dissociates from initial contacts and migrates to secondary sites. We recently reported that in hepatocytes the multifunctional cytokine TGFβ induces a full EMT characterized by (i) Snail induction, (ii) E-cadherin delocalization and down-regulation, (iii) down-regulation of the hepatocyte transcriptional factor HNF4α and (iv) up-regulation of mesenchymal and invasiveness markers. In particular, we showed that Snail directly causes the transcriptional down-regulation of E-cadherin and HN…

Transcriptional ActivationTGFβFAK; MT; Src; TGFβ; Animals; Biomarkers Tumor; Cadherins; Cell Line; Cell Transformation Neoplastic; Enzyme Activation; Epithelial Cells; Focal Adhesion Protein-Tyrosine Kinases; Hepatocytes; Liver Neoplasms; Mesoderm; Mice; Neoplasm Invasiveness; Signal Transduction; Transcriptional Activation; Transforming Growth Factor beta; Up-Regulation; src-Family Kinases; Cell BiologyCell LineMesodermFocal adhesionMiceTransforming Growth Factor betaBiomarkers TumorAnimalsHepatocyteNeoplasm InvasivenessNeoplasm InvasiveneEpithelial CellFocal Adhesion Protein-Tyrosine KinaseFAKbiologyAnimalCadherinLiver NeoplasmsMesenchymal stem cellEpithelial CellsCell BiologyTransforming growth factor betaTgf beta; fak; srcCadherinsUp-RegulationCell biologyEnzyme ActivationCell Transformation Neoplasticsrc-Family KinasesHepatocyte nuclear factor 4Liver NeoplasmTumor progressionMTFocal Adhesion Protein-Tyrosine KinasesCadherinHepatocytesCancer researchbiology.proteinsrc-Family KinaseSignal transductionSrcSignal TransductionProto-oncogene tyrosine-protein kinase SrcExperimental Cell Research
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Transcriptional Regulation of Human CYP3A4 Basal Expression by CCAAT Enhancer-Binding Protein α and Hepatocyte Nuclear Factor-3γ

2003

Cytochrome P450 3A4 (CYP3A4) is involved in the metabolism of more than 50% of currently used therapeutic drugs, yet the mechanisms that control CYP3A4 basal expression in liver are poorly understood. Several putative binding sites for CCAAT/enhancer-binding protein (C/EBP) and hepatic nuclear factor 3 (HNF-3) were found by computer analysis in CYP3A4 promoter. The use of reporter gene assays, electrophoretic mobility shift assays, and site-directed mutagenesis revealed that one proximal and two distal C/EBP alpha binding sites are essential sites for the trans-activation of CYP3A4 promoter. No trans-activation was found in similar reporter gene experiments with a HNF-3 gamma expression vec…

Transcriptional ActivationTranscription GeneticGenetic VectorsBiologyTransfectiondigestive systemGene Expression Regulation EnzymologicChromatin remodelingAdenoviridaeCytochrome P-450 Enzyme SystemCCAAT-Enhancer-Binding Protein-alphamedicineCytochrome P-450 CYP3AHumansEnzyme InhibitorsBinding sitePromoter Regions GeneticCells CulturedPharmacologyReporter geneExpression vectorCcaat-enhancer-binding proteinsNuclear ProteinsMolecular biologyChromatinDNA-Binding ProteinsHistone Deacetylase InhibitorsHepatocyte nuclear factorsTrichostatin AHepatocytesMolecular MedicineHepatocyte Nuclear Factor 3-gammaTranscription Factorsmedicine.drugMolecular Pharmacology
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