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Ozolins T R - - 1999
Oxidative stress in the conceptus is characterized by an increased oxidized to reduced glutathione (GSSG:GSH) ratio and the induction of fos and jun mRNAs, transcripts for components of the activator protein-1 (AP-1) transcription factor. We investigated the role of glutathione homeostasis in the rat conceptus in the regulation of: (1) ...
Fu S l - - 1999
Jun is a transcription factor belonging to the activator protein 1 family. A mutated version of Jun (v-Jun) transduced by the avian retrovirus ASV17 induces oncogenic transformation in avian cell cultures and sarcomas in young galliform birds. The oncogenicity of Jun probably results from transcriptional deregulation of v-Jun-responsive target genes. ...
Boudreau F - - 1999
In order to investigate the regulatory mechanisms involved in the expression of fos and jun family members by glucocorticoids, and the effect of ras transformation in intestinal epithelial cells, we used the rat cell line IEC-6. Dexamethasone treatment induced transiently c-jun mRNAs, in contrast to the sustained expression of c-fos, ...
Rahmani M - - 1999
BACKGROUND/AIMS: Stimulation of activator protein-1 (AP-1), a Fos/Jun complex, is a key event in the cell response to growth factors. We have investigated whether hepatocyte growth factor (HGF) induces differential AP-1 responses in normal and transformed rat hepatocytes, the 7777 cells. METHODS: Primocultures of isolated hepatocytes or 7777 cells were ...
Spindler B - - 1999
Adrenal steroids induce an increase in transcellular Na+ reabsorption across Xenopus laevis A6 cell epithelia that requires the action of transcriptionally regulated gene products. In a previous study we identified K-ras2 as an aldosterone-upregulated mRNA in A6 epithelia. Here, we show that in vivo injection of aldosterone in Xenopus (2.5 ...
Hoare S - - 1999
Oxytocin (OT) receptors (OTRs) mediate reproductive functions, including the initiation of labor and milk ejection. OTR messenger RNA levels are highly regulated, reaching the greatest concentration in the uterus at the end of gestation, and in the mammary gland during lactation. Factors directly effecting changes in OTR gene expression in ...
Deyama A - - 1999
Animals fed a low calcium diet develop hypocalcemia and osteoporotic bone. Earlier we conjectured that a low calcium environment might be one of the factors causing abnormalities in hard tissues. Osteoblastic MC3T3-E1 cells (E1 cells) undergo a process of proliferation and differentiation and then produce small mineralized nodules. In this ...
Kreuzer J - - 1999
Hydroxymethylglutaryl-Coenzyme A (HMG-CoA) reductase inhibitors were shown to be effective in primary and secondary prevention of coronary heart disease. The beneficial effect of statins is generally attributed to their cholesterol lowering activity. However recent work points to additional cholesterol independent effects of these drugs on cellular signal transduction. In this ...
Kumagae Y - - 1999
Differential expression and localization of c-Jun N-terminal kinases (JNKs) in the human brain may reflect transduction of a variety of extracellular stimuli to selective cellular responses. Of the three JNKs, JNK1 and 2 are widely distributed in tissues and JNK3 is predominantly restricted to brain where it is expressed in ...
Lukasiuk K - - 1999
In the studies reported herein, electrophoretic mobility shift assay (EMSA) and immunocytochemistry have been applied to document increased levels of AP-1 transcription factor, and its major component, c-Fos in the rat brain following behavioral training of two-way active avoidance. A single training session (50 trials) provoked elevation of AP-1 in ...
Salvat C - - 1999
The c-Fos and c-Jun oncoproteins and the p53 tumor suppressor protein are short-lived transcription factors. Several catabolic pathways contribute to their degradation in vivo. c-Fos and c-Jun are thus mostly degraded by the proteasome, but there is indirect evidence that, under certain experimental/physiological conditions, calpains participate in their destruction, at ...
Kim I J - - 1999
Stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) is activated by a variety of cellular or environmental stresses. Proper regulation of the SAPK/JNK pathway may be critical for cell survival or death under various conditions. In this study, we report the molecular cloning of novel isoforms of JIP-1, which harbor a putative ...
Kaiser A - - 1999
Using a cDNA gene expression array system, we identified fra-1 as a novel target molecule for retinoid action in the human pancreatic carcinoma cell line Dan-G. Retinoid treatment resulted in a significant and time-dependent induction of the fra-1 expression on the post-transcriptional level. Supershift assays revealed that fra-1 participates in ...
Lu X - - 1999
Hepatic transcription of insulin-like growth factor binding protein-1 (IGFBP-1) is rapidly downregulated by growth hormone (GH) which is also known to induce expression of c-fos and c-jun. Co-expression of c-fos or c-jun in rat hepatocytes, individually or together, suppresses IGFBP-1 promoter activity by approximately 60%. When hepatic nuclear extracts from ...
Woodgate A - - 1999
We have developed a model of nerve cell death based on the toxicity of okadaic acid, a compound that triggers apoptosis in PC12 cells via a protein synthesis-dependent mechanism. The cell death process is accompanied by induction of JunB, c-Jun, JunD and Fos proteins. Phosphorylation-specific antibodies were used to demonstrate ...
Frank R C - - 1999
The 8;21 translocation is the most common cytogenetic abnormality in human acute myelogenous leukemia, joining the AML1 gene on chromosome 21, to the ETO gene on chromosome 8, forming the AML1/ETO fusion gene. The AMLI/ETO fusion protein has been shown to function mainly as a transcriptional repressor of AML1 target ...
Kouretas D - - 1999
Glucocorticoids are a very potent therapy for the treatment of asthma as well for lung maturation in the prematurely newborn animals and human. It has been demonstrated that glucocorticoid receptors antagonize the actions of inflammatory mediators through control of the specific DNA binding of the transcriptions factors c-Jun and c-Fos, ...
Li Q - - 1999
ERCC-1 is an essential gene in the nucleotide excision repair pathway, and may be essential for life. However, the mechanism of transcriptional activation and regulation of ERCC-1 gene expression is unclear. We therefore investigated the effect of the phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate (TPA) on the expression of the ERCC-1 gene in ...
Wong C - - 1999
Transcriptional regulation by transforming growth factor beta (TGF-beta) is a complex process which is likely to involve cross talk between different DNA responsive elements and transcription factors to achieve maximal promoter activation and specificity. Here, we describe a concurrent requirement for two discrete responsive elements in the regulation of the ...
Bergman A C - - 1999
Signalling via the protein kinase Raf-MEK-ERK pathway is of major importance for transformation by oncogenes. To identify genes affected by inhibition of this pathway, c-JUN transformed rat fibroblasts were treated with a MEK1 inhibitor (PD98059) and subjected to two-dimensional gel electrophoresis after cell lysis. Gene products with expression influenced by ...
Oren A - - 1999
The physical and functional link between adhesion molecules and the cytoskeletal network suggests that the cytoskeleton might mediate the transduction of cell-to-cell contact signals, which often regulate growth and differentiation in an antagonistic manner. Depolymerization of the cytoskeleton in confluent cell cultures is reportedly sufficient to initiate DNA synthesis. Here ...
Bahr M J - - 1999
In the injured liver hepatic stellate cells (HSCs) undergo a dramatic phenotypic transformation known as "activation" in which they become myofibroblast-like and express high levels of the tissue inhibitor of metalloproteinase 1 (TIMP-1). HSC activation is accompanied by transactivation of the TIMP-1 promoter. Truncation mutagenesis studies delineated a minimal active ...
Schreiber M - - 1999
The c-jun proto-oncogene encodes a component of the mitogen-inducible immediate-early transcription factor AP-1 and has been implicated as a positive regulator of cell proliferation and G1-to-S-phase progression. Here we report that fibroblasts derived from c-jun-/- mouse fetuses exhibit a severe proliferation defect and undergo a prolonged crisis before spontaneous immortalization. ...
Behre G - - 1999
The ETS domain transcription factor PU.1 is necessary for the development of monocytes and regulates, in particular, the expression of the monocyte-specific macrophage colony-stimulating factor (M-CSF) receptor, which is critical for monocytic cell survival, proliferation, and differentiation. The bZIP transcription factor c-Jun, which is part of the AP-1 transcription factor ...
Li Q - - 1999
Excision repair cross complementation group 1 (ERCC-1) is a DNA repair gene that is essential for life, and it appears to be a marker gene for nucleotide excision repair activity. Overexpression of ERCC-1 during cisplatin-based chemotherapy is associated with clinical and cellular drug resistance. We therefore began to assess the ...
Wickström H R - - 1999
In situ hybridization was used to characterize respiration-related areas of the brainstem activated around the time of birth as well as their postnatal sensitivity to CO2. Levels of mRNA corresponding to the immediate early genes (IEG), c-fos and c-jun, and of substance P precursor, ppt-A, were determined in rat fetuses ...
Shin H M - - 1999
Within a few minutes of T-cell activation, transcription of a set of genes including c-fos and c-jun is activated. For maximal induction of c-jun, at least two major signal pathways are required. One can be triggered by T-cell receptor engagement or phorbol esters and the other by anti-CD28 engagement. The ...
François-Bellan A M - - 1999
Expression of immediate early genes, including fos-like and jun-like genes, in the suprachiasmatic nucleus is believed to be part of the mechanism for photic entrainment of circadian rhythms to the environmental light/dark cycle. However, the effects of a light stimulus on activating protein-1 (AP-1) complexes in the suprachiasmatic nucleus remain ...
Daschner P J - - 1999
The expression, DNA binding, and transactivating activity of activator protein 1 (AP-1) was examined in a series of multidrug resistant (MDR) MCF-7 human breast cancer cells that have increasing levels of MDR1 gene expression. We observed an increase in the amount of both c-jun and c-fos mRNA in cells with ...
Oo T F - - 1999
The transcription factors c-fos and c-jun have been proposed to play a role in the initiation of programmed cell death in neurons. We have shown that programmed cell death, with the morphology of apoptosis, occurs in dopamine neurons of the substantia nigra (SN) during normal postnatal development and that this ...
Chida K - - 1999
Jun and Fos, b-ZIP transcription factors, form a heterodimer and bind to DNA enhancer elements, thereby regulating the expression of target genes. The present study was undertaken to investigate the molecular mechanism underlying nuclear translocation of the Jun/Fos complex. For this purpose, normal rat kidney cells were microinjected with a ...
Kitamura C - - 1999
c-jun and jun-B are nuclear proto-oncogenes induced by growth factors such as bone morphogenetic proteins (BMPs). These gene products enhance the expression of many genes, including osteocalcin and collagen types, indicating that c-jun and jun-B play important roles in the cell differentiation process. It is also known that BMPs affect ...
Zhou X F - - 1999
In the presence of retinoic acid (RA), the retinoid receptors, retinoic acid receptor (RAR) and retinoid X receptor (RXR), are able to up-regulate transcription directly by binding to RA-responsive elements on the promoters of responsive genes. Liganded RARs and RXRs are also capable of down-regulating transcription, but, by contrast, this ...
Salehi M - - 1999
We have examined the expression of the fos and jun genes in the cerebellum of the rat brain during ageing, by use of a semi-quantitative fluorescence in situ hybridization (FISH) method. In these experiments we have utilised the digital imaging capabilities of a cooled CCD camera system to store the ...
Lapperre T S - - 1999
Apocynin (4-hydroxy-3-methoxy-acetophenone) is a potent intracellular inhibitor of superoxide anion production in neutrophils. In this study, we studied the effect of apocynin on the regulation of the antioxidant glutathione (GSH) and activation of the transcription factor AP-I in human alveolar epithelial cells (A549). Apocynin enhanced intracellular GSH by increasing gamma-glutamylcysteine ...
McKay R A - - 1999
The use of antisense oligonucleotides to inhibit the expression of targeted mRNA sequences is becoming increasingly commonplace. Although effective, the most widely used oligonucleotide modification (phosphorothioate) has some limitations. In previous studies we have described a 20-mer phosphorothioate oligodeoxynucleotide inhibitor of human protein kinase C-alpha expression. In an effort to ...
Cook S J - - 1999
In Rat-1 fibroblasts nonmitogenic doses of lysophosphatidic acid (LPA) stimulate a transient activation of mitogen-activated protein kinase (MAPK), whereas mitogenic doses elicit a sustained response. This sustained phase of MAPK activation regulates cell fate decisions such as proliferation or differentiation, presumably by inducing a program of gene expression which is ...
Mu D - - 1999
OBJECTIVE: To investigate the relationship between c-jun mRNA and apoptosis of neurons following perinatal ischemic-hypoxia. METHODS: We set up a fetal rat model of perinatal ischemic-hypoxia by ligating unilateral uterine horn vessel of pregnant Wistar rats (21-day gestation). The contralateral horn vessel was not ligated and the fetuses in these ...
Gibellini D - - 1999
We have previously demonstrated that the addition in culture of recombinant HIV-1 IIIB envelope gp120 affects the survival/growth of pluripotent haemopoietic progenitors, and, in particular, of those committed towards the megakaryocytic lineage. To characterize some of the molecular mechanisms involved in this phenomenon, we investigated the expression of members of ...
Watts R G - - 1998
The mitogen activated protein (MAP) kinases or extracellular signal-regulated kinases (Erks) are activated in response to Ras expression or exposure to tumor promoters or to growth factors, and have been implicated in AP-1 transactivation in some models. We have shown that tumor promoter induced activation of the transcription factor AP-1 ...
Venugopal R - - 1998
Antioxidant response element (ARE)-mediated expression and coordinated induction of genes encoding detoxifying enzymes is one mechanism of critical importance to cellular protection against oxidative stress. In the present report, we demonstrate that nuclear transcription factors Nrf2 and Nrf1 associate with Jun (c-Jun, Jun-B and Jun-D) proteins to upregulate ARE-mediated expression ...
Chihab R - - 1998
Previous studies have demonstrated that transient hypoxia (6 h) induces apoptotic death in cultured neurons isolated from the fetal rat forebrain. Since activation of c-Jun N-terminal kinases (JNKs) and subsequent phosphorylation of c-Jun are suspected to be involved in the apoptotic pathway in several cell types, the time course of ...
Sundstedt A - - 1998
The transcription factor activating protein-1 (AP-1) contributes significantly to the regulation of IL-2 gene expression during T cell activation and has been suggested to play a unique role in T cell anergy in vitro. In this study we have used the superantigen staphylococcal enterotoxin A to investigate the regulation of ...
Houle J D - - 1998
Cervical, but not thoracic spinal cord injury upregulates, in certain brainstem neurons, the expression of c-Jun, an inducible transcription factor that may be involved in the regenerative program/cell body response to injury. This study was designed to evaluate changes in c-Jun expression over a long period after spinal cord injury ...
Herdegen T - - 1998
This article reviews findings up to the end of 1997 about the inducible transcription factors (ITFs) c-Jun, JunB, JunD, c-Fos, FosB, Fra-1, Fra-2, Krox-20 (Egr-2) and Krox-24 (NGFI-A, Egr-1, Zif268); and the constitutive transcription factors (CTFs) CREB, CREM, ATF-2 and SRF as they pertain to gene expression in the mammalian ...
Ding W Q - - 1998
This study describes the effects of acute ethanol exposure on the mRNA levels of c-jun,junB and junD in the human neuroblastoma SH-SY5Y cell line. An acute exposure to 100 mM ethanol did not influence the basal and phorbol ester-induced expression of c-jun and junB, whereas the basal mRNA level of ...
Chen W - - 1998
The effects of UVB irradiation on transcription factor activator protein-1 (AP-1) DNA binding and AP-1 transactivation were studied in a human keratinocyte cell line, HaCaT. UVB-induced AP-1 binding to a consensus AP-1 binding site was observed by gel shift assays with maximum stimulation at 12 h after UVB irradiation. A ...
Koul D - - 1998
Murine p202 is an interferon-inducible primarily nuclear phosphoprotein (52 kDa) whose expression in transfected cells inhibits colony formation. p202-binding proteins include the pocket proteins (pRb, p107 and p130), a p53-binding protein (sm53BP1), and transcription factors (e.g. NF-kappaB (p50 and p65), AP-1 (c-Fos and c-Jun), E2F-1, E2F-4, MyoD, and myogenin). p202 ...
Huttunen P - - 1998
We have previously shown that echovirus 1 (EV1) infection increases the mRNA levels of cellular immediate-early (IE) genes in host cells. Here we provide further evidence that the induction of junB, c-jun, and c-fos genes is due to active viral macromolecular synthesis rather than to the interaction of EV1 with ...
Hadzopoulou-Cladaras M - - 1998
It was shown previously that cytokines such as tumor necrosis factor-alpha that stimulate signal transduction pathways involving transcription factors ATF-2 and Jun repress apoCIII promoter activity in HepG2 cells. In the present study, DNase I footprinting analysis established that ATF-2 protected three regions in the apoCIII promoter. One region (-747/-726) ...
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