p53 and ATF4 mediate distinct and additive pathways to skeletal muscle atrophy during limb immobilization

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Fox, Daniel K.; Ebert, Scott M.; Bongers, Kale S.; Dyle, Michael C.; Bullard, Steven A.; Dierdorff, Jason M.; Kunkel, Steven D.

2014-01-01

Immobilization causes skeletal muscle atrophy via complex signaling pathways that are not well understood. To better understand these pathways, we investigated the roles of p53 and ATF4, two transcription factors that mediate adaptations to a variety of cellular stresses. Using mouse models, we demonstrate that 3 days of muscle immobilization induces muscle atrophy and increases expression of p53 and ATF4. Furthermore, muscle fibers lacking p53 or ATF4 are partially resistant to immobilization-induced muscle atrophy, and forced expression of p53 or ATF4 induces muscle fiber atrophy in the absence of immobilization. Importantly, however, p53 and ATF4 do not require each other to promote atrophy, and coexpression of p53 and ATF4 induces more atrophy than either transcription factor alone. Moreover, muscle fibers lacking both p53 and ATF4 are more resistant to immobilization-induced atrophy than fibers lacking only p53 or ATF4. Interestingly, the independent and additive nature of the p53 and ATF4 pathways allows for combinatorial control of at least one downstream effector, p21. Using genome-wide mRNA expression arrays, we identified p21 mRNA as a skeletal muscle transcript that is highly induced in immobilized muscle via the combined actions of p53 and ATF4. Additionally, in mouse muscle, p21 induces atrophy in a manner that does not require immobilization, p53 or ATF4, and p21 is required for atrophy induced by immobilization, p53, and ATF4. Collectively, these results identify p53 and ATF4 as essential and complementary mediators of immobilization-induced muscle atrophy and discover p21 as a critical downstream effector of the p53 and ATF4 pathways. PMID:24895282

Essential role of eIF5-mimic protein in animal development is linked to control of ATF4 expression

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Translational control of ATF4 through upstream ORFs (uORFs) plays an important role in eukaryotic gene regulation. While ATF4 translation is typically induced by inhibitory phosphorylation of eIF2, ATF4 translation can be also induced by expression of a new translational inhibitor protein, eIF5-mimi...

MicroRNA-214 Suppresses Osteogenic Differentiation of Human Periodontal Ligament Stem Cells by Targeting ATF4

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Siqi Yao

2017-01-01

Full Text Available Periodontitis is the main cause of adult tooth loss. Stem cell-based tissue engineering has become a promising therapy for periodontitis treatment. To date, human periodontal ligament stem cells (hPDLSCs have been shown to be a favorable source for tissue engineering, but modulatory mechanisms of hPDLSCs remain unclear. Approximately 60% of mammalian genes are the targets of over 2000 miRNAs in multiple human cell types, and miRNAs are able to influence various biological processes in the human body, including bone formation. In this study, we found that after osteogenic induction, miR-214 was significantly decreased in hPDLSCs; therefore, we examined the effects of miR-214 on osteogenic differentiation. Computational miRNA target prediction analyses and luciferase reporter assays revealed that activating transcription factor 4 (ATF4 is a direct target of miR-214. We prepared cells overexpressing miR-214 and found that miR-214 negatively regulates osteogenic differentiation of hPDLSCs. For the target of miR-214, ATF4 protein expression level was decreased after induction. In conclusion, we found that miR-214-ATF4 axis is a novel pathway for regulating hPDLSC osteogenic differentiation.

Isoproterenol Increases RANKL Expression in a ATF4/NFATc1-Dependent Manner in Mouse Osteoblastic Cells

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Kyunghwa Baek

2017-10-01

Full Text Available Sympathetic nervous system stimulation-induced β-adrenergic signal transduction is known to induce bone loss and increase of osteoclast activity. Although isoproterenol, a nonspecific β-adrenergic receptor agonist, has been shown to increase receptor activator of NF-κB ligand (RANKL, the details of the regulatory mechanisms remain unclear. In the present study, we investigated the role of the nuclear factor of activated T-cells (NFAT in isoproterenol-induced RANKL expression in C2C12 and in primary cultured mouse calvarial cells. Isoproterenol increased nuclear factor of activated T-cells cytoplasmic 1 (NFATc1 and RANKL expressions at both mRNA and protein levels and increased NFAT reporter activity. NFATc1 knockdown blocked isoproterenol-mediated RANKL expression. Isoproterenol also promoted cAMP response element-binding protein 1 (CREB1 and activating transcription factor 4 (ATF4 phosphorylation. Isoproterenol-mediated transcriptional activation of NFAT was blocked by protein kinase A (PKA inhibitor H89. Isoproterenol-induced CREB1, ATF4, NFATc1, and RANKL expressions were suppressed by H89. Mutations in cAMP response element-like or NFAT-binding element suppressed isoproterenol-induced RANKL promoter activity. Chromatin immunoprecipitation analysis demonstrated that isoproterenol increased NFAT-binding and ATF4-binding activities on the mouse RANKL promoter, but did not increase CREB1-binding activity. Association of NFATc1 and ATF4 was not observed in a co-immunoprecipitation study. ATF4 knockdown suppressed isoproterenol-induced NFAT binding to the RANKL promoter, whereas NFATc1 knockdown did not suppress isoproterenol-induced ATF4 binding to the RANKL promoter. ATF4 knockdown suppressed isoproterenol-induced expressions of NFATc1 and RANKL. These results suggest that isoproterenol increases RANKL expression in an ATF4/NFATc1-dependent manner.

The transcription factor ATF3 is upregulated during chondrocyte differentiation and represses cyclin D1 and A gene transcription

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James Claudine G

2006-09-01

Full Text Available Abstract Background Coordinated chondrocyte proliferation and differentiation are required for normal endochondral bone growth. Transcription factors binding to the cyclicAMP response element (CRE are known to regulate these processes. One member of this family, Activating Tanscription Factor 3 (ATF3, is expressed during skeletogenesis and acts as a transcriptional repressor, but the function of this protein in chondrogenesis is unknown. Results Here we demonstrate that Atf3 mRNA levels increase during mouse chondrocyte differentiation in vitro and in vivo. In addition, Atf3 mRNA levels are increased in response to cytochalasin D treatment, an inducer of chondrocyte maturation. This is accompanied by increased Atf3 promoter activity in cytochalasin D-treated chondrocytes. We had shown earlier that transcription of the cell cycle genes cyclin D1 and cyclin A in chondrocytes is dependent on CREs. Here we demonstrate that overexpression of ATF3 in primary mouse chondrocytes results in reduced transcription of both genes, as well as decreased activity of a CRE reporter plasmid. Repression of cyclin A transcription by ATF3 required the CRE in the cyclin A promoter. In parallel, ATF3 overexpression reduces the activity of a SOX9-dependent promoter and increases the activity of a RUNX2-dependent promoter. Conclusion Our data suggest that transcriptional induction of the Atf3 gene in maturing chondrocytes results in down-regulation of cyclin D1 and cyclin A expression as well as activation of RUNX2-dependent transcription. Therefore, ATF3 induction appears to facilitate cell cycle exit and terminal differentiation of chondrocytes.

Activating transcription factor 4 underlies the pathogenesis of arsenic trioxide-mediated impairment of macrophage innate immune functions

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Srivastava, Ritesh K.; Li, Changzhao [Department of Dermatology and Skin Diseases Research Center, University of Alabama at Birmingham, Birmingham, AL (United States); Wang, Yong [Department of Medicine, University of Alabama at Birmingham, Birmingham, AL (United States); Weng, Zhiping; Elmets, Craig A. [Department of Dermatology and Skin Diseases Research Center, University of Alabama at Birmingham, Birmingham, AL (United States); Harrod, Kevin S. [Department of Anesthesiology and Perioperative Medicine, University of Alabama at Birmingham, Birmingham, AL (United States); Deshane, Jessy S., E-mail: treena@uab.edu [Department of Medicine, University of Alabama at Birmingham, Birmingham, AL (United States); Athar, Mohammad, E-mail: mathar@uab.edu [Department of Dermatology and Skin Diseases Research Center, University of Alabama at Birmingham, Birmingham, AL (United States)

2016-10-01

Chronic arsenic exposure to humans is considered immunosuppressive with augmented susceptibility to several infectious diseases. The exact molecular mechanisms, however, remain unknown. Earlier, we showed the involvement of unfolded protein response (UPR) signaling in arsenic-mediated impairment of macrophage functions. Here, we show that activating transcription factor 4 (ATF4), a UPR transcription factor, regulates arsenic trioxide (ATO)-mediated dysregulation of macrophage functions. In ATO-treated ATF4{sup +/+} wild-type mice, a significant down-regulation of CD11b expression was associated with the reduced phagocytic functions of peritoneal and lung macrophages. This severe immuno-toxicity phenotype was not observed in ATO-treated ATF4{sup +/−} heterozygous mice. To confirm these observations, we demonstrated in Raw 264.7 cells that ATF4 knock-down rescues ATO-mediated impairment of macrophage functions including cytokine production, bacterial engulfment and clearance of engulfed bacteria. Sustained activation of ATF4 by ATO in macrophages induces apoptosis, while diminution of ATF4 expression protects against ATO-induced apoptotic cell death. Raw 264.7 cells treated with ATO also manifest dysregulated Ca{sup ++} homeostasis. ATO induces Ca{sup ++}-dependent calpain-1 and caspase-12 expression which together regulated macrophage apoptosis. Additionally, apoptosis was also induced by mitochondria-regulated pathway. Restoring ATO-impaired Ca{sup ++} homeostasis in ER/mitochondria by treatments with the inhibitors of inositol 1,4,5-trisphosphate receptor (IP3R) and voltage-dependent anion channel (VDAC) attenuate innate immune functions of macrophages. These studies identify a novel role for ATF4 in underlying pathogenesis of macrophage dysregulation and immuno-toxicity of arsenic. - Highlights: • ATF4 regulates arsenic-mediated impairment in macrophage functions. • Arsenic-mediated alterations in pulmonary macrophage are diminished in ATF4{sup +/−} mice

Activating transcription factor 4 underlies the pathogenesis of arsenic trioxide-mediated impairment of macrophage innate immune functions

International Nuclear Information System (INIS)

Srivastava, Ritesh K.; Li, Changzhao; Wang, Yong; Weng, Zhiping; Elmets, Craig A.; Harrod, Kevin S.; Deshane, Jessy S.; Athar, Mohammad

2016-01-01

Chronic arsenic exposure to humans is considered immunosuppressive with augmented susceptibility to several infectious diseases. The exact molecular mechanisms, however, remain unknown. Earlier, we showed the involvement of unfolded protein response (UPR) signaling in arsenic-mediated impairment of macrophage functions. Here, we show that activating transcription factor 4 (ATF4), a UPR transcription factor, regulates arsenic trioxide (ATO)-mediated dysregulation of macrophage functions. In ATO-treated ATF4 +/+ wild-type mice, a significant down-regulation of CD11b expression was associated with the reduced phagocytic functions of peritoneal and lung macrophages. This severe immuno-toxicity phenotype was not observed in ATO-treated ATF4 +/− heterozygous mice. To confirm these observations, we demonstrated in Raw 264.7 cells that ATF4 knock-down rescues ATO-mediated impairment of macrophage functions including cytokine production, bacterial engulfment and clearance of engulfed bacteria. Sustained activation of ATF4 by ATO in macrophages induces apoptosis, while diminution of ATF4 expression protects against ATO-induced apoptotic cell death. Raw 264.7 cells treated with ATO also manifest dysregulated Ca ++ homeostasis. ATO induces Ca ++ -dependent calpain-1 and caspase-12 expression which together regulated macrophage apoptosis. Additionally, apoptosis was also induced by mitochondria-regulated pathway. Restoring ATO-impaired Ca ++ homeostasis in ER/mitochondria by treatments with the inhibitors of inositol 1,4,5-trisphosphate receptor (IP3R) and voltage-dependent anion channel (VDAC) attenuate innate immune functions of macrophages. These studies identify a novel role for ATF4 in underlying pathogenesis of macrophage dysregulation and immuno-toxicity of arsenic. - Highlights: • ATF4 regulates arsenic-mediated impairment in macrophage functions. • Arsenic-mediated alterations in pulmonary macrophage are diminished in ATF4 +/− mice. • Changes in macrophage

ATF3 inhibits PPARγ-stimulated transactivation in adipocyte cells

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Jang, Min-Kyung; Jung, Myeong Ho, E-mail: jung0603@pusan.ac.kr

2015-01-02

Highlights: • ATF3 inhibits PPARγ-stimulated transcriptional activation. • ATF3 interacts with PPARγ. • ATF3 suppresses p300-mediated transcriptional coactivation. • ATF3 decreases the binding of PPARγ and recruitment of p300 to PPRE. - Abstract: Previously, we reported that activating transcription factor 3 (ATF3) downregulates peroxisome proliferator activated receptor (PPARγ) gene expression and inhibits adipocyte differentiation in 3T3-L1 cells. Here, we investigated another role of ATF3 on the regulation of PPARγ activity. ATF3 inhibited PPARγ-stimulated transactivation of PPARγ responsive element (PPRE)-containing reporter or GAL4/PPARγ chimeric reporter. Thus, ATF3 effectively repressed rosiglitazone-stimulated expression of adipocyte fatty acid binding protein (aP2), PPARγ target gene, in 3T3-L1 cells. Coimmunoprecipitation and GST pulldown assay demonstrated that ATF3 interacted with PPARγ. Accordingly, ATF3 prevented PPARγ from binding to PPRE on the aP2 promoter. Furthermore, ATF3 suppressed p300-mediated transcriptional coactivation of PPRE-containing reporter. Chromatin immunoprecipitation assay showed that overexpression of ATF3 blocked both binding of PPARγ and recruitment of p300 to PPRE on aP2 promoter induced by rosiglitazone treatment in 3T3-L1 cells. Taken together, these results suggest that ATF3 interacts with PPARγ and represses PPARγ-mediated transactivation through suppression of p300-stimulated coactivation in 3T3-L1 cells, which may play a role in inhibition of adipocyte differentiation.

The CDK inhibitor p21 is a novel target gene of ATF4 and contributes to cell survival under ER stress.

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Inoue, Yasumichi; Kawachi, Shiori; Ohkubo, Tsubasa; Nagasaka, Mai; Ito, Shogo; Fukuura, Keishi; Itoh, Yuka; Ohoka, Nobumichi; Morishita, Daisuke; Hayashi, Hidetoshi

2017-11-01

Activating transcription factor 4 (ATF4) is well known for its role in the endoplasmic reticulum (ER) stress response. ATF4 also transcriptionally induces multiple effectors that determine cell fate depending on cellular context. In addition, ATF4 can communicate both pro-apoptotic and pro-survival signals. How ATF4 mediates its prosurvival roles, however, requires further investigation. Here, we report that the CDK inhibitor p21 is a novel target gene of ATF4. We identified two ATF4-responsive elements, one of which directly binds ATF4, within the first intron of the p21 gene. Importantly, overexpression of p21 enhances cell survival following ER stress induction, while p21 knockdown increases cell death. These results suggest that p21 induction plays a vital role in the cellular response to ER stress and indicate that p21 is a prosurvival effector of ATF4. © 2017 Federation of European Biochemical Societies.

The cellular transcription factor CREB corresponds to activating transcription factor 47 (ATF-47) and forms complexes with a group of polypeptides related to ATF-43.

OpenAIRE

Hurst, H C; Masson, N; Jones, N C; Lee, K A

1990-01-01

Promoter elements containing the sequence motif CGTCA are important for a variety of inducible responses at the transcriptional level. Multiple cellular factors specifically bind to these elements and are encoded by a multigene family. Among these factors, polypeptides termed activating transcription factor 43 (ATF-43) and ATF-47 have been purified from HeLa cells and a factor referred to as cyclic AMP response element-binding protein (CREB) has been isolated from PC12 cells and rat brain. We...

VEGF-A isoforms differentially regulate ATF-2-dependent VCAM-1 gene expression and endothelial-leukocyte interactions.

Science.gov (United States)

Fearnley, Gareth W; Odell, Adam F; Latham, Antony M; Mughal, Nadeem A; Bruns, Alexander F; Burgoyne, Nicholas J; Homer-Vanniasinkam, Shervanthi; Zachary, Ian C; Hollstein, Monica C; Wheatcroft, Stephen B; Ponnambalam, Sreenivasan

2014-08-15

Vascular endothelial growth factor A (VEGF-A) regulates many aspects of vascular physiology. VEGF-A stimulates signal transduction pathways that modulate endothelial outputs such as cell migration, proliferation, tubulogenesis, and cell-cell interactions. Multiple VEGF-A isoforms exist, but the biological significance of this is unclear. Here we analyzed VEGF-A isoform-specific stimulation of VCAM-1 gene expression, which controls endothelial-leukocyte interactions, and show that this is dependent on both ERK1/2 and activating transcription factor-2 (ATF-2). VEGF-A isoforms showed differential ERK1/2 and p38 MAPK phosphorylation kinetics. A key feature of VEGF-A isoform-specific ERK1/2 activation and nuclear translocation was increased phosphorylation of ATF-2 on threonine residue 71 (T71). Using reverse genetics, we showed ATF-2 to be functionally required for VEGF-A-stimulated endothelial VCAM-1 gene expression. ATF-2 knockdown blocked VEGF-A-stimulated VCAM-1 expression and endothelial-leukocyte interactions. ATF-2 was also required for other endothelial cell outputs, such as cell migration and tubulogenesis. In contrast, VCAM-1 was essential only for promoting endothelial-leukocyte interactions. This work presents a new paradigm for understanding how soluble growth factor isoforms program complex cellular outputs and responses by modulating signal transduction pathways. © 2014 Fearnley et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Cryptocephal, the Drosophila melanogaster ATF4, is a specific coactivator for ecdysone receptor isoform B2.

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Sebastien A Gauthier

Full Text Available The ecdysone receptor is a heterodimer of two nuclear receptors, the Ecdysone receptor (EcR and Ultraspiracle (USP. In Drosophila melanogaster, three EcR isoforms share common DNA and ligand-binding domains, but these proteins differ in their most N-terminal regions and, consequently, in the activation domains (AF1s contained therein. The transcriptional coactivators for these domains, which impart unique transcriptional regulatory properties to the EcR isoforms, are unknown. Activating transcription factor 4 (ATF4 is a basic-leucine zipper transcription factor that plays a central role in the stress response of mammals. Here we show that Cryptocephal (CRC, the Drosophila homolog of ATF4, is an ecdysone receptor coactivator that is specific for isoform B2. CRC interacts with EcR-B2 to promote ecdysone-dependent expression of ecdysis-triggering hormone (ETH, an essential regulator of insect molting behavior. We propose that this interaction explains some of the differences in transcriptional properties that are displayed by the EcR isoforms, and similar interactions may underlie the differential activities of other nuclear receptors with distinct AF1-coactivators.

Ku70 acetylation and modulation of c-Myc/ATF4/CHOP signaling axis by SIRT1 inhibition lead to sensitization of HepG2 cells to TRAIL through induction of DR5 and down-regulation of c-FLIP

DEFF Research Database (Denmark)

Kim, Mi-Ju; Hong, Kyung-Soo; Kim, Hak-Bong

2013-01-01

In this study, we investigated the role of c-Myc/ATF4/CHOP signaling pathway in sensitization of human hepatoma HepG2 cells to TRAIL. Knockdown of SIRT1 or treatment with SIRT1 inhibitor caused the up-regulation of DR5 and down-regulation of c-FLIP through modulation of c-Myc/ATF4/CHOP pathway, a...

MicroRNA-214 Suppresses Gluconeogenesis by Targeting Activating Transcriptional Factor 4*

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Li, Kai; Zhang, Jin; Yu, Junjie; Liu, Bin; Guo, Yajie; Deng, Jiali; Chen, Shanghai; Wang, Chunxia; Guo, Feifan

2015-01-01

Although the gluconeogenesis pathway is already a target for the treatment of type 2 diabetes, the potential role of microRNAs (miRNAs) in gluconeogenesis remains unclear. Here, we investigated the physiological functions of miR-214 in gluconeogenesis. The expression of miR-214 was suppressed by glucagon via protein kinase A signaling in primary hepatocytes, and miR-214 was down-regulated in the livers of fasted, high fat diet-induced diabetic and leptin receptor-mutated (db/db) mice. The overexpression of miR-214 in primary hepatocytes suppressed glucose production, and silencing miR-214 reversed this effect. Gluconeogenesis was suppressed in the livers of mice injected with an adenovirus expressing miR-214 (Ad-miR-214). Additionally, Ad-miR-214 alleviated high fat diet-induced elevation of gluconeogenesis and hyperglycemia. Furthermore, we found that activating transcription factor 4 (ATF4), a reported target of miR-214, can reverse the suppressive effect of miR-214 on gluconeogenesis in primary hepatocytes, and this suppressive effect was blocked in liver-specific ATF4 knock-out mice. ATF4 regulated gluconeogenesis via affecting forkhead box protein O1 (FOXO1) transcriptional activity. Finally, liver-specific miR-214 transgenic mice exhibited suppressed gluconeogenesis and reduced expression of ATF4, phosphoenolpyruvate carboxykinase, and glucose-6-phosphatase in liver. Taken together, our results suggest that the miR-214-ATF4 axis is a novel pathway for the regulation of hepatic gluconeogenesis. PMID:25657009

Activating Transcription Factor 3 regulates in part the enhanced tumour cell cytotoxicity of the histone deacetylase inhibitor M344 and cisplatin in combination

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St Germain Carly

2010-09-01

Full Text Available Abstract Background Activating Transcription Factor (ATF 3 is a key regulator of the cellular integrated stress response whose expression has also been correlated with pro-apoptotic activities in tumour cell models. Combination treatments with chemotherapeutic drugs, such as cisplatin, and histone deacetylase (HDAC inhibitors have been demonstrated to enhance tumour cell cytotoxicity. We recently demonstrated a role for ATF3 in regulating cisplatin-induced apoptosis and others have shown that HDAC inhibition can also induce cellular stress. In this study, we evaluated the role of ATF3 in regulating the co-operative cytotoxicity of cisplatin in combination with an HDAC inhibitor. Results The HDAC inhibitor M344 induced ATF3 expression at the protein and mRNA level in a panel of human derived cancer cell lines as determined by Western blot and quantitative RT-PCR analyses. Combination treatment with M344 and cisplatin lead to increased induction of ATF3 compared with cisplatin alone. Utilizing the MTT cell viability assay, M344 treatments also enhanced the cytotoxic effects of cisplatin in these cancer cell lines. The mechanism of ATF3 induction by M344 was found to be independent of MAPKinase pathways and dependent on ATF4, a known regulator of ATF3 expression. ATF4 heterozygote (+/- and knock out (-/- mouse embryonic fibroblast (MEF as well as chromatin immunoprecipitation (ChIP assays were utilized in determining the mechanistic induction of ATF3 by M344. We also demonstrated that ATF3 regulates the enhanced cytotoxicity of M344 in combination with cisplatin as evidenced by attenuation of cytotoxicity in shRNAs targeting ATF3 expressing cells. Conclusion This study identifies the pro-apoptotic factor, ATF3 as a novel target of M344, as well as a mediator of the co-operative effects of cisplatin and M344 induced tumour cell cytotoxicity.

ATF3 represses PPARγ expression and inhibits adipocyte differentiation

Energy Technology Data Exchange (ETDEWEB)

Jang, Min-Kyung; Jung, Myeong Ho, E-mail: jung0603@pusan.ac.kr

2014-11-07

Highlights: • ATF3 decrease the expression of PPARγ and its target gene in 3T3-L1 adipocytes. • ATF3 represses the promoter activity of PPARγ2 gene. • ATF/CRE (−1537/−1530) is critical for ATF3-mediated downregulation of PPARγ. • ATF3 binds to the promoter region containing the ATF/CRE. • ER stress inhibits adipocyte differentiation through downregulation of PPARγ by ATF3. - Abstract: Activating transcription factor 3 (ATF3) is a stress-adaptive transcription factor that mediates cellular stress response signaling. We previously reported that ATF3 represses CCAAT/enhancer binding protein α (C/EBPα) expression and inhibits 3T3-L1 adipocyte differentiation. In this study, we explored potential role of ATF3 in negatively regulating peroxisome proliferator activated receptor-γ (PPARγ). ATF3 decreased the expression of PPARγ and its target gene in 3T3-L1 adipocytes. ATF3 also repressed the activity of −2.6 Kb promoter of mouse PPARγ2. Overexpression of PPARγ significantly prevented the ATF3-mediated inhibition of 3T3-L1 differentiation. Transfection studies with 5′ deleted-reporters showed that ATF3 repressed the activity of −2037 bp promoter, whereas it did not affect the activity of −1458 bp promoter, suggesting that ATF3 responsive element is located between the −2037 and −1458. An electrophoretic mobility shift assay and chromatin immunoprecipitation assay demonstrated that ATF3 binds to ATF/CRE site (5′-TGACGTTT-3′) between −1537 and −1530. Mutation of the ATF/CRE site abrogated ATF3-mediated transrepression of the PPARγ2 promoter. Treatment with thapsigargin, endoplasmic reticulum (ER) stress inducer, increased ATF3 expression, whereas it decreased PPARγ expression. ATF3 knockdown significantly blocked the thapsigargin-mediated downregulation of PPARγ expression. Furthermore, overexpression of PPARγ prevented inhibition of 3T3-L1 differentiation by thapsigargin. Collectively, these results suggest that ATF3-mediated

ATF3, an HTLV-1 bZip factor binding protein, promotes proliferation of adult T-cell leukemia cells

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Ohshima Koichi

2011-03-01

Full Text Available Abstract Background Adult T-cell leukemia (ATL is an aggressive malignancy of CD4+ T-cells caused by human T-cell leukemia virus type 1 (HTLV-1. The HTLV-1 bZIP factor (HBZ gene, which is encoded by the minus strand of the viral genome, is expressed as an antisense transcript in all ATL cases. By using yeast two-hybrid screening, we identified activating transcription factor 3 (ATF3 as an HBZ-interacting protein. ATF3 has been reported to be expressed in ATL cells, but its biological significance is not known. Results Immunoprecipitation analysis confirmed that ATF3 interacts with HBZ. Expression of ATF3 was upregulated in ATL cell lines and fresh ATL cases. Reporter assay revealed that ATF3 could interfere with the HTLV-1 Tax's transactivation of the 5' proviral long terminal repeat (LTR, doing so by affecting the ATF/CRE site, as well as HBZ. Suppressing ATF3 expression inhibited proliferation and strongly reduced the viability of ATL cells. As mechanisms of growth-promoting activity of ATF3, comparative expression profiling of ATF3 knockdown cells identified candidate genes that are critical for the cell cycle and cell death, including cell division cycle 2 (CDC2 and cyclin E2. ATF3 also enhanced p53 transcriptional activity, but this activity was suppressed by HBZ. Conclusions Thus, ATF3 expression has positive and negative effects on the proliferation and survival of ATL cells. HBZ impedes its negative effects, leaving ATF3 to promote proliferation of ATL cells via mechanisms including upregulation of CDC2 and cyclin E2. Both HBZ and ATF3 suppress Tax expression, which enables infected cells to escape the host immune system.

Metformin-induced inhibition of the mitochondrial respiratory chain increases FGF21 expression via ATF4 activation

International Nuclear Information System (INIS)

Kim, Kook Hwan; Jeong, Yeon Taek; Kim, Seong Hun; Jung, Hye Seung; Park, Kyong Soo; Lee, Hae-Youn; Lee, Myung-Shik

2013-01-01

Highlights: •Metformin induces FGF21 expression in an AMPK independent manner. •Metformin enhances FGF21 expression by inhibiting mitochondrial complex I activity. •The PERK-eIF2α-ATF4 axis is required for metformin-induced FGF21 expression. •Metformin activates the ATF4-FGF21 axis in the liver of mouse. •Metformin increases serum FGF21 level in diabetic human subjects. -- Abstract: Fibroblast growth factor 21 (FGF21) is an endocrine hormone that exhibits anti-obesity and anti-diabetes effects. Because metformin is widely used as a glucose-lowering agent in patients with type 2 diabetes (T2D), we investigated whether metformin modulates FGF21 expression in cell lines, and in mice or human subjects. We found that metformin increased the expression and release of FGF21 in a diverse set of cell types, including rat hepatoma FaO, primary mouse hepatocytes, and mouse embryonic fibroblasts (MEFs). Intriguingly, AMP-activated protein kinase (AMPK) was dispensable for the induction of FGF21 by metformin. Mammalian target of rapamycin complex 1 (mTORC1) and peroxisome proliferator-activated receptor α (PPARα), which are additional targets of metformin, were not involved in metformin-induced FGF21 expression. Importantly, inhibition of mitochondrial complex I activity by metformin resulted in FGF21 induction through PKR-like ER kinase (PERK)-eukaryotic translation factor 2α (eIF2α)-activating transcription factor 4 (ATF4). We showed that metformin activated ATF4 and increased FGF21 expression in the livers of mice, which led to increased serum levels of FGF21. We also found that serum FGF21 level was increased in human subjects with T2D after metformin therapy for 6 months. In conclusion, our results indicate that metformin induced expression of FGF21 through an ATF4-dependent mechanism by inhibiting mitochondrial respiration independently of AMPK. Therefore, FGF21 induction by metformin might explain a portion of the beneficial metabolic effects of metformin

Metformin-induced inhibition of the mitochondrial respiratory chain increases FGF21 expression via ATF4 activation

Energy Technology Data Exchange (ETDEWEB)

Kim, Kook Hwan [Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong Gangnam-gu, Seoul 135-710 (Korea, Republic of); Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University School of Medicine, 50 Irwon-dong Gangnam-gu, Seoul 135-710 (Korea, Republic of); Jeong, Yeon Taek [Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong Gangnam-gu, Seoul 135-710 (Korea, Republic of); Kim, Seong Hun [Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University School of Medicine, 50 Irwon-dong Gangnam-gu, Seoul 135-710 (Korea, Republic of); Jung, Hye Seung; Park, Kyong Soo [Department of Internal Medicine, Seoul National University College of Medicine, 28 Yongon-dong Chongno-gu, Seoul 110-744 (Korea, Republic of); Lee, Hae-Youn [Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong Gangnam-gu, Seoul 135-710 (Korea, Republic of); Lee, Myung-Shik, E-mail: mslee0923@skku.edu [Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong Gangnam-gu, Seoul 135-710 (Korea, Republic of); Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University School of Medicine, 50 Irwon-dong Gangnam-gu, Seoul 135-710 (Korea, Republic of)

2013-10-11

Highlights: •Metformin induces FGF21 expression in an AMPK independent manner. •Metformin enhances FGF21 expression by inhibiting mitochondrial complex I activity. •The PERK-eIF2α-ATF4 axis is required for metformin-induced FGF21 expression. •Metformin activates the ATF4-FGF21 axis in the liver of mouse. •Metformin increases serum FGF21 level in diabetic human subjects. -- Abstract: Fibroblast growth factor 21 (FGF21) is an endocrine hormone that exhibits anti-obesity and anti-diabetes effects. Because metformin is widely used as a glucose-lowering agent in patients with type 2 diabetes (T2D), we investigated whether metformin modulates FGF21 expression in cell lines, and in mice or human subjects. We found that metformin increased the expression and release of FGF21 in a diverse set of cell types, including rat hepatoma FaO, primary mouse hepatocytes, and mouse embryonic fibroblasts (MEFs). Intriguingly, AMP-activated protein kinase (AMPK) was dispensable for the induction of FGF21 by metformin. Mammalian target of rapamycin complex 1 (mTORC1) and peroxisome proliferator-activated receptor α (PPARα), which are additional targets of metformin, were not involved in metformin-induced FGF21 expression. Importantly, inhibition of mitochondrial complex I activity by metformin resulted in FGF21 induction through PKR-like ER kinase (PERK)-eukaryotic translation factor 2α (eIF2α)-activating transcription factor 4 (ATF4). We showed that metformin activated ATF4 and increased FGF21 expression in the livers of mice, which led to increased serum levels of FGF21. We also found that serum FGF21 level was increased in human subjects with T2D after metformin therapy for 6 months. In conclusion, our results indicate that metformin induced expression of FGF21 through an ATF4-dependent mechanism by inhibiting mitochondrial respiration independently of AMPK. Therefore, FGF21 induction by metformin might explain a portion of the beneficial metabolic effects of metformin.

MicroRNA-214 suppresses gluconeogenesis by targeting activating transcriptional factor 4.

Science.gov (United States)

Li, Kai; Zhang, Jin; Yu, Junjie; Liu, Bin; Guo, Yajie; Deng, Jiali; Chen, Shanghai; Wang, Chunxia; Guo, Feifan

2015-03-27

Although the gluconeogenesis pathway is already a target for the treatment of type 2 diabetes, the potential role of microRNAs (miRNAs) in gluconeogenesis remains unclear. Here, we investigated the physiological functions of miR-214 in gluconeogenesis. The expression of miR-214 was suppressed by glucagon via protein kinase A signaling in primary hepatocytes, and miR-214 was down-regulated in the livers of fasted, high fat diet-induced diabetic and leptin receptor-mutated (db/db) mice. The overexpression of miR-214 in primary hepatocytes suppressed glucose production, and silencing miR-214 reversed this effect. Gluconeogenesis was suppressed in the livers of mice injected with an adenovirus expressing miR-214 (Ad-miR-214). Additionally, Ad-miR-214 alleviated high fat diet-induced elevation of gluconeogenesis and hyperglycemia. Furthermore, we found that activating transcription factor 4 (ATF4), a reported target of miR-214, can reverse the suppressive effect of miR-214 on gluconeogenesis in primary hepatocytes, and this suppressive effect was blocked in liver-specific ATF4 knock-out mice. ATF4 regulated gluconeogenesis via affecting forkhead box protein O1 (FOXO1) transcriptional activity. Finally, liver-specific miR-214 transgenic mice exhibited suppressed gluconeogenesis and reduced expression of ATF4, phosphoenolpyruvate carboxykinase, and glucose-6-phosphatase in liver. Taken together, our results suggest that the miR-214-ATF4 axis is a novel pathway for the regulation of hepatic gluconeogenesis. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

ATF4-Induced Metabolic Reprograming Is a Synthetic Vulnerability of the p62-Deficient Tumor Stroma.

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Linares, Juan F; Cordes, Thekla; Duran, Angeles; Reina-Campos, Miguel; Valencia, Tania; Ahn, Christopher S; Castilla, Elias A; Moscat, Jorge; Metallo, Christian M; Diaz-Meco, Maria T

2017-12-05

Tumors undergo nutrient stress and need to reprogram their metabolism to survive. The stroma may play a critical role in this process by providing nutrients to support the epithelial compartment of the tumor. Here we show that p62 deficiency in stromal fibroblasts promotes resistance to glutamine deprivation by the direct control of ATF4 stability through its p62-mediated polyubiquitination. ATF4 upregulation by p62 deficiency in the stroma activates glucose carbon flux through a pyruvate carboxylase-asparagine synthase cascade that results in asparagine generation as a source of nitrogen for stroma and tumor epithelial proliferation. Thus, p62 directly targets nuclear transcription factors to control metabolic reprogramming in the microenvironment and repress tumorigenesis, and identifies ATF4 as a synthetic vulnerability in p62-deficient tumor stroma. Copyright © 2017 Elsevier Inc. All rights reserved.

TPL2 (Therapeutic Targeting Tumor Progression Locus-2)/ATF4 (Activating Transcription Factor-4)/SDF1α (Chemokine Stromal Cell-Derived Factor-α) Axis Suppresses Diabetic Retinopathy.

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Lai, De-Wei; Lin, Keng-Hung; Sheu, Wayne Huey-Herng; Lee, Maw-Rong; Chen, Chung-Yu; Lee, Wen-Jane; Hung, Yi-Wen; Shen, Chin-Chang; Chung, Tsung-Ju; Liu, Shing-Hwa; Sheu, Meei-Ling

2017-09-01

Diabetic retinopathy is characterized by vasopermeability, vascular leakage, inflammation, blood-retinal barrier breakdown, capillary degeneration, and neovascularization. However, the mechanisms underlying the association between diabetes mellitus and progression retinopathy remain unclear. TPL2 (tumor progression locus 2), a serine-threonine protein kinase, exerts a pathological effect on vascular angiogenesis. This study investigated the role of N ε -(carboxymethyl)lysine, a major advanced glycation end products, and the involved TPL2-related molecular signals in diabetic retinopathy using models of in vitro and in vivo and human samples. Serum N ε -(carboxymethyl)lysine levels and TPL2 kinase activity were significantly increased in clinical patients and experimental animals with diabetic retinopathy. Intravitreal administration of pharmacological blocker or neutralizing antibody inhibited TPL2 and effectively suppressed the pathological characteristics of retinopathy in streptozotocin-induced diabetic animal models. Intravitreal VEGF (vascular endothelial growth factor) neutralization also suppressed the diabetic retinopathy in diabetic animal models. Mechanistic studies in primary human umbilical vein endothelial cells and primary retinal microvascular endothelial cells from streptozotocin-diabetic rats, db/db mice, and samples from patients with diabetic retinopathy revealed a positive parallel correlation between N ε -(carboxymethyl)lysine and the TPL2/chemokine SDF1α (stromal cell-derived factor-α) axis that is dependent on endoplasmic reticulum stress-related molecules, especially ATF4 (activating transcription factor-4). This study demonstrates that inhibiting the N ε -(carboxymethyl)lysine-induced TPL2/ATF4/SDF1α axis can effectively prevent diabetes mellitus-mediated retinal microvascular dysfunction. This signaling axis may include the therapeutic potential for other diseases involving pathological neovascularization or macular edema. © 2017

Lipopolysaccharide preconditioning protects hepatocytes from ischemia/reperfusion injury (IRI through inhibiting ATF4-CHOP pathway in mice.

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Jianhua Rao

Full Text Available BACKGROUND: Low-dose lipopolysaccharide (LPS preconditioning-induced liver protection has been demonstrated during ischemia-reperfusion injury (IRI in several organs but has not been sufficiently elucidated underlying causal mechanism. This study investigated the role of low-dose LPS preconditioning on ATF4-CHOP pathway as well as the effects of the pathway on tissue injury and inflammation in a mouse model of liver partial-warm IRI. METHODS: LPS (100 µg/kg/d was injected intraperitoneally two days before ischemia. Hepatic injury was evaluated based on serum alanine aminotransferase levels, histopathology, and caspase-3 activity. The ATF4-CHOP pathway and its related apoptotic molecules were investigated after reperfusion. The role of LPS preconditioning on apoptosis and ATF4-CHOP pathway was examined in vitro. Moreover, the effects of the ATF4-CHOP pathway on apoptosis, Caspase-12, and Caspase-3 were determined with ATF4 small interfering RNA (siRNA. Inflammatory cytokine expression was also checked after reperfusion. Inflammatory cytokines and related signaling pathways were analyzed in vitro in macrophages treated by LPS preconditioning or ATF4 siRNA. RESULTS: LPS preconditioning significantly attenuated liver injury after IRI. As demonstrated by in vitro experiments, LPS preconditioning significantly reduced the upregulation of the ATF4-CHOP pathway and inhibited Caspase-12 and Caspase-3 activation after IRI. Later experiments showed that ATF4 knockdown significantly suppressed CHOP, cleaved caspase-12 and caspase-3 expression, as well as inhibited hepatocellular apoptosis. In addition, in mice pretreated with LPS, TNF-α and IL-6 were inhibited after reperfusion, whereas IL-10 was upregulated. Similarly, low-dose LPS significantly inhibited TNF-α, IL-6, ATF4-CHOP pathway, NF-κB pathway, and ERK1/2 in high-dose LPS-stimulated macrophages, whereas IL-10 and cytokine signaling (SOCS-3 suppressor were induced. Importantly, ATF4 siRNA is

Cardiac glycoside ouabain induces activation of ATF-1 and StAR expression by interacting with the α4 isoform of the sodium pump in Sertoli cells.

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Dietze, Raimund; Konrad, Lutz; Shihan, Mazen; Kirch, Ulrike; Scheiner-Bobis, Georgios

2013-03-01

Sertoli cells express α1 and α4 isoforms of the catalytic subunit of Na(+),K(+)-ATPase (sodium pump). Our recent findings demonstrated that interactions of the α4 isoform with cardiotonic steroids (CTS) like ouabain induce signaling cascades that resemble the so-called non-classical testosterone pathway characterized by activation of the c-Src/c-Raf/Erk1/2/CREB signaling cascade. Here we investigate a possible physiological significance of the activated cascade. The results obtained in the current investigation show that the ouabain-induced signaling cascade also leads to the activation of the CREB-related activating transcription factor 1 (ATF-1) in the Sertoli cell line 93RS2 in a concentration- and time-dependent manner, as demonstrated by detection of ATF-1 phosphorylated on Ser63 in western blots. The ouabain-activated ATF-1 protein was found to localize to the cell nuclei. The sodium pump α4 isoform mediates this activation, as it is ablated when cells are incubated with siRNA to the α4 isoform. Ouabain also leads to increased expression of steroidogenic acute regulator (StAR) protein, which has been shown to be a downstream consequence of CREB/ATF-1 activation. Taking into consideration that CTS are most likely produced endogenously, the demonstrated induction of StAR expression by ouabain establishes a link between CTS, the α4 isoform of the sodium pump, and steroidogenesis crucial for male fertility and reproduction. Copyright © 2012 Elsevier B.V. All rights reserved.

Distinct Residues Contribute to Motility Repression and Autoregulation in the Proteus mirabilis Fimbria-Associated Transcriptional Regulator AtfJ.

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Bode, Nadine J; Chan, Kun-Wei; Kong, Xiang-Peng; Pearson, Melanie M

2016-08-01

Proteus mirabilis contributes to a significant number of catheter-associated urinary tract infections, where coordinated regulation of adherence and motility is critical for ascending disease progression. Previously, the mannose-resistant Proteus-like (MR/P) fimbria-associated transcriptional regulator MrpJ has been shown to both repress motility and directly induce the transcription of its own operon; in addition, it affects the expression of a wide range of cellular processes. Interestingly, 14 additional mrpJ paralogs are included in the P. mirabilis genome. Looking at a selection of MrpJ paralogs, we discovered that these proteins, which consistently repress motility, also have nonidentical functions that include cross-regulation of fimbrial operons. A subset of paralogs, including AtfJ (encoded by the ambient temperature fimbrial operon), Fim8J, and MrpJ, are capable of autoinduction. We identified an element of the atf promoter extending from 487 to 655 nucleotides upstream of the transcriptional start site that is responsive to AtfJ, and we found that AtfJ directly binds this fragment. Mutational analysis of AtfJ revealed that its two identified functions, autoregulation and motility repression, are not invariably linked. Residues within the DNA-binding helix-turn-helix domain are required for motility repression but not necessarily autoregulation. Likewise, the C-terminal domain is dispensable for motility repression but is essential for autoregulation. Supported by a three-dimensional (3D) structural model, we hypothesize that the C-terminal domain confers unique regulatory capacities on the AtfJ family of regulators. Balancing adherence with motility is essential for uropathogens to successfully establish a foothold in their host. Proteus mirabilis uses a fimbria-associated transcriptional regulator to switch between these antagonistic processes by increasing fimbrial adherence while simultaneously downregulating flagella. The discovery of multiple

Endoplasmic reticulum stress-responsive transcription factor ATF6α directs recruitment of the Mediator of RNA polymerase II transcription and multiple histone acetyltransferase complexes.

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Sela, Dotan; Chen, Lu; Martin-Brown, Skylar; Washburn, Michael P; Florens, Laurence; Conaway, Joan Weliky; Conaway, Ronald C

2012-06-29

The basic leucine zipper transcription factor ATF6α functions as a master regulator of endoplasmic reticulum (ER) stress response genes. Previous studies have established that, in response to ER stress, ATF6α translocates to the nucleus and activates transcription of ER stress response genes upon binding sequence specifically to ER stress response enhancer elements in their promoters. In this study, we investigate the biochemical mechanism by which ATF6α activates transcription. By exploiting a combination of biochemical and multidimensional protein identification technology-based mass spectrometry approaches, we have obtained evidence that ATF6α functions at least in part by recruiting to the ER stress response enhancer elements of ER stress response genes a collection of RNA polymerase II coregulatory complexes, including the Mediator and multiple histone acetyltransferase complexes, among which are the Spt-Ada-Gcn5 acetyltransferase (SAGA) and Ada-Two-A-containing (ATAC) complexes. Our findings shed new light on the mechanism of action of ATF6α, and they outline a straightforward strategy for applying multidimensional protein identification technology mass spectrometry to determine which RNA polymerase II transcription factors and coregulators are recruited to promoters and other regulatory elements to control transcription.

Advanced Toroidal Facility (ATF)

International Nuclear Information System (INIS)

Thompson, P.B.

1985-01-01

The Advanced Toroidal Facility (ATF) is a new magnetic plasma confinement device, under construction at Oak Ridge National Laboratory (ORNL), which will lead to improvements in toroidal magnetic fusion reactors. ATF is a type of stellarator known as a torsatron which theoretically has the capability at greater than or equal to8% beta in steady state. The ATF plasma has a major radius of 2.1 m, an average minor radius of 0.3 m, and a field of 2 T for a 5-s duration or 1 T steady state. The ATF device consists of a helical field (HF) coil set, a set of poloidal field (PF) coils, an exterior shell structure to support the coils, and a thin helically contoured vacuum vessel inside the coils. The ATF replaces the ISX-B tokamak at ORNL and will use the ISX-B auxiliary systems including 4 MW of neutral injection heating and 0.2 MW of electron cyclotron heating. ATF device is scheduled to start operation in the fall of 1986. An overview of the ATF device is presented including details of the construction process envisioned

ATF3 activates Stat3 phosphorylation through inhibition of p53 expression in skin cancer cells.

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Hao, Zhen-Feng; Ao, Jun-Hong; Zhang, Jie; Su, You-Ming; Yang, Rong-Ya

2013-01-01

ATF3, a member of the ATF/CREB family of transcription factors, has been found to be selectively induced by calcineurin/NFAT inhibition and to enhance keratinocyte tumor formation, although the precise role of ATF3 in human skin cancer and possible mechanisms remain unknown. In this study, clinical analysis of 30 skin cancer patients and 30 normal donors revealed that ATF3 was accumulated in skin cancer tissues. Functional assays demonstrated that ATF3 significantly promoted skin cancer cell proliferation. Mechanically, ATF3 activated Stat3 phosphorylation in skin cancer cell through regulation of p53 expression. Moreover, the promotion effect of ATF3 on skin cancer cell proliferation was dependent on the p53-Stat3 signaling cascade. Together, the results indicate that ATF3 might promote skin cancer cell proliferation and enhance skin keratinocyte tumor development through inhibiting p53 expression and then activating Stat3 phosphorylation.

Overexpression of eIF5 or its protein mimic 5MP perturbs eIF2 function and induces ATF4 translation through delayed re-initiation.

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Kozel, Caitlin; Thompson, Brytteny; Hustak, Samantha; Moore, Chelsea; Nakashima, Akio; Singh, Chingakham Ranjit; Reid, Megan; Cox, Christian; Papadopoulos, Evangelos; Luna, Rafael E; Anderson, Abbey; Tagami, Hideaki; Hiraishi, Hiroyuki; Slone, Emily Archer; Yoshino, Ken-Ichi; Asano, Masayo; Gillaspie, Sarah; Nietfeld, Jerome; Perchellet, Jean-Pierre; Rothenburg, Stefan; Masai, Hisao; Wagner, Gerhard; Beeser, Alexander; Kikkawa, Ushio; Fleming, Sherry D; Asano, Katsura

2016-10-14

ATF4 is a pro-oncogenic transcription factor whose translation is activated by eIF2 phosphorylation through delayed re-initiation involving two uORFs in the mRNA leader. However, in yeast, the effect of eIF2 phosphorylation can be mimicked by eIF5 overexpression, which turns eIF5 into translational inhibitor, thereby promoting translation of GCN4, the yeast ATF4 equivalent. Furthermore, regulatory protein termed eIF5-mimic protein (5MP) can bind eIF2 and inhibit general translation. Here, we show that 5MP1 overexpression in human cells leads to strong formation of 5MP1:eIF2 complex, nearly comparable to that of eIF5:eIF2 complex produced by eIF5 overexpression. Overexpression of eIF5, 5MP1 and 5MP2, the second human paralog, promotes ATF4 expression in certain types of human cells including fibrosarcoma. 5MP overexpression also induces ATF4 expression in Drosophila The knockdown of 5MP1 in fibrosarcoma attenuates ATF4 expression and its tumor formation on nude mice. Since 5MP2 is overproduced in salivary mucoepidermoid carcinoma, we propose that overexpression of eIF5 and 5MP induces translation of ATF4 and potentially other genes with uORFs in their mRNA leaders through delayed re-initiation, thereby enhancing the survival of normal and cancer cells under stress conditions. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Mineral trioxide aggregate induces osteoblastogenesis via Atf6

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Toyonobu Maeda

2015-06-01

Full Text Available Mineral trioxide aggregate (MTA has been recommended for various uses in endodontics. To understand the effects of MTA on alveolar bone, we examined whether MTA induces osteoblastic differentiation using MC3T3-E1 cells. MTA enhanced mineralization concomitant with alkaline phosphatase activity in a dose- and time-dependent manner. MTA increased production of collagens (Type I and Type III and matrix metalloproteinases (MMP-9 and MMP-13, suggesting that MTA affects bone matrix remodeling. MTA also induced Bglap (osteocalcin but not Bmp2 (bone morphogenetic protein-2 mRNA expression. We observed induction of Atf6 (activating transcription factor 6, an endoplasmic reticulum (ER stress response transcription factor mRNA expression and activation of Atf6 by MTA treatment. Forced expression of p50Atf6 (active form of Atf6 markedly enhanced Bglap mRNA expression. Chromatin immunoprecipitation assay was performed to investigate the increase in p50Atf6 binding to the Bglap promoter region by MTA treatment. Furthermore, knockdown of Atf6 gene expression by introduction of Tet-on Atf6 shRNA expression vector abrogated MTA-induced mineralization. These results suggest that MTA induces in vitro osteoblastogenesis through the Atf6–osteocalcin axis as ER stress signaling. Therefore, MTA in endodontic treatment may affect alveolar bone healing in the resorbed region caused by pulpal infection.

Social isolation stress induces ATF-7 phosphorylation and impairs silencing of the 5-HT 5B receptor gene

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Maekawa, Toshio; Kim, Seungjoon; Nakai, Daisuke; Makino, Chieko; Takagi, Tsuyoshi; Ogura, Hiroo; Yamada, Kazuyuki; Chatton, Bruno; Ishii, Shunsuke

2010-01-01

Many symptoms induced by isolation rearing of rodents may be relevant to neuropsychiatric disorders, including depression. However, identities of transcription factors that regulate gene expression in response to chronic social isolation stress remain elusive. The transcription factor ATF-7 is structurally related to ATF-2, which is activated by various stresses, including inflammatory cytokines. Here, we report that Atf-7-deficient mice exhibit abnormal behaviours and increased 5-HT receptor 5B (Htr5b) mRNA levels in the dorsal raphe nuclei. ATF-7 silences the transcription of Htr5B by directly binding to its 5′-regulatory region, and mediates histone H3-K9 trimethylation via interaction with the ESET histone methyltransferase. Isolation-reared wild-type (WT) mice exhibit abnormal behaviours that resemble those of Atf-7-deficient mice. Upon social isolation stress, ATF-7 in the dorsal raphe nucleus is phosphorylated via p38 and is released from the Htr5b promoter, leading to the upregulation of Htr5b. Thus, ATF-7 may have a critical role in gene expression induced by social isolation stress. PMID:19893493

ATF2 Commissioning

Energy Technology Data Exchange (ETDEWEB)

Seryi, A.; /SLAC; Christian, G.; /KLTE-ATOMKI; Parker, B.; /BNL; Schulte, D.; Delahaye, J.-P.; Tomas, R.; Zimmermann, F.; /CERN; Wolski, A.; Elsen, E.; /Cockcroft Inst. /DESY; Sanuki, T.; /Tohoku U.; Gianfelice-Wendt, E.; Ross, M.; Wendt, M.; /Fermilab; Takahashi, T.; /Hiroshima U.; Bai, S.; Gao, J.; /Beijing, Inst. High Energy Phys.; Bolzon, B.; Geffroy, N.; Jeremie, A.; /Annecy, LAPP; Apsimon, R.; Burrows, P.; /Oxford U., JAI /Kyoto U., Inst. Chem. Res. /Kyungpook Natl. U. /Orsay, LAL /Phang Accelerator Lab /Royal Holloway, U. of London /SLAC /Daresbury /University Coll. London /Manchester U. /Univ. of Tokyo U.

2009-10-30

ATF2 is a final-focus test beam line that aims to focus the low-emittance beam from the ATF damping ring to a beam size of about 37 nm, and at the same time to demonstrate nm beam stability, using numerous advanced beam diagnostics and feedback tools. The construction has been finished at the end of 2008 and the beam commissioning of ATF2 has started in December of 2008. ATF2 is constructed and commissioned by ATF international collaborations with strong US, Asian and European participation.

ATF2 COMMISSIONING

CERN Document Server

Seryi, A; Parker, B; Schulte, D; Delahaye, J P; Tomas, R; Zimmermann, F; Wolski, A; Elsen, E; Sanuki, T; Gianfelice-Wendt, E; Ross, M; Wendt, M; Takahashi, T; Bai, S; Gao, J; Bolzon, B; Geffroy, N; Jeremie, A; Apsimon, R; Burrows, P; Constance, B; Perry, C; Resta-Lopez, J; Swinson, C; Araki, S; Aryshev, A; Hayano, H; Honda, Y; Kubo, K; Kume, T; Kuroda, S; Masuzawa, M; Naito, T; Okugi, T; Sugahara, R; Tauchi, T; Terunuma, N; Urakawa, J; Yokoya, K; Iwashita, Y; Sugimoto, T; Heo, A Y; Kim, E S; Kim, H S; Bambade, P; Renier, Y; Rimbault, C; Huang, J Y; Kim, S H; Park, Y J; Hwang, W H; Blair, G; Boogert, S; Karataev, P; Molloy, S; Amann, J; Bellomo, P; Lam, B; McCormick, D; Nelson, J; Paterson, E; Pivi, M; Raubenheimer, T; Spencer, C; Wang, M H; White, G; Wittmer, W; Woodley, M; Yan, Y; Zhou, F; Angal-Kalinin, D; Jones, J; Lyapin, A; Scarfe, A; Kamiya, Y; Komamiya, S; Oroku, M; Suehara, T; Yamanaka, T

2010-01-01

ATF2 is a final-focus test beam line that aims to focus the low-emittance beam from the ATF damping ring to a beam size of about 37 nm, and at the same time to demonstrate nm beam stability, using numerous advanced beam diagnostics and feedback tools. The construction has been finished at the end of 2008 and the beam commissioning of ATF2 has started in December of 2008. ATF2 is constructed and commissioned by ATF international collaborations with strong US, Asian and European participation.

ATF3 mediates inhibitory effects of ethanol on hepatic gluconeogenesis.

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Tsai, Wen-Wei; Matsumura, Shigenobu; Liu, Weiyi; Phillips, Naomi G; Sonntag, Tim; Hao, Ergeng; Lee, Soon; Hai, Tsonwin; Montminy, Marc

2015-03-03

Increases in circulating glucagon during fasting maintain glucose balance by stimulating hepatic gluconeogenesis. Acute ethanol intoxication promotes fasting hypoglycemia through an increase in hepatic NADH, which inhibits hepatic gluconeogenesis by reducing the conversion of lactate to pyruvate. Here we show that acute ethanol exposure also lowers fasting blood glucose concentrations by inhibiting the CREB-mediated activation of the gluconeogenic program in response to glucagon. Ethanol exposure blocked the recruitment of CREB and its coactivator CRTC2 to gluconeogenic promoters by up-regulating ATF3, a transcriptional repressor that also binds to cAMP-responsive elements and thereby down-regulates gluconeogenic genes. Targeted disruption of ATF3 decreased the effects of ethanol in fasted mice and in cultured hepatocytes. These results illustrate how the induction of transcription factors with overlapping specificity can lead to cross-coupling between stress and hormone-sensitive pathways.

Activating transcription factor 6 mediates oxidized LDL-induced cholesterol accumulation and apoptosis in macrophages by up-regulating CHOP expression.

Science.gov (United States)

Yao, Shutong; Zong, Chuanlong; Zhang, Ying; Sang, Hui; Yang, Mingfeng; Jiao, Peng; Fang, Yongqi; Yang, Nana; Song, Guohua; Qin, Shucun

2013-01-01

This study was to explore whether activating transcription factor 6 (ATF6), an important sensor to endoplasmic reticulum (ER) stress, would mediate oxidized low-density lipoprotein (ox-LDL)- induced cholesterol accumulation and apoptosis in cultured macrophages and the underlying molecular mechanisms. Intracellular lipid droplets and total cholesterol levels were assayed by oil red O staining and enzymatic colorimetry, respectively. Cell viability and apoptosis were determined using MTT assay and AnnexinV-FITC apoptosis detection kit, respectively. The nuclear translocation of ATF6 in cells was detected by immunofluorescence analysis. Protein and mRNA levels were examined by Western blot analysis and real time-PCR, respectively. ATF6 siRNA was transfected to RAW264.7 cells by lipofectamin. Exposure of cells to ox-LDL induced glucose-regulated protein 78 (GRP78). C/EBP homologous protein (CHOP), a key-signaling component of ER stress-induced apoptosis, was up-regulated in ox-LDL-treated cells. ATF6, a factor that positively regulates CHOP expression, was activated by ox-LDL in a concentration- and time- dependent manner. The role of the ATF6-mediated ER stress pathway was further confirmed through the siRNA-mediated knockdown of ATF6, which attenuated ox-LDL-induced upregulation of CHOP, cholesterol accumulation and apoptosis in macrophages. In addition, the phosphorylation of double-stranded RNA-activated protein kinase-like endoplasmic reticulum kinase (PERK), another factor that positively regulates CHOP expression, was induced in the presence of ox-LDL, and PERK-specific siRNA also inhibited the ox-LDL-induced upregulation of CHOP and apoptosis in RAW264.7 cells. These results demonstrate that ER stress-related proteins, particularly ATF6 and its downstream molecule CHOP, are involved in ox-LDL-induced cholesterol accumulation and apoptosis in macrophages.

Deciphering the role of the signal- and Sty1 kinase-dependent phosphorylation of the stress-responsive transcription factor Atf1 on gene activation.

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Salat-Canela, Clàudia; Paulo, Esther; Sánchez-Mir, Laura; Carmona, Mercè; Ayté, José; Oliva, Baldo; Hidalgo, Elena

2017-08-18

Adaptation to stress triggers the most dramatic shift in gene expression in fission yeast ( Schizosaccharomyces pombe ), and this response is driven by signaling via the MAPK Sty1. Upon activation, Sty1 accumulates in the nucleus and stimulates expression of hundreds of genes via the nuclear transcription factor Atf1, including expression of atf1 itself. However, the role of stress-induced, Sty1-mediated Atf1 phosphorylation in transcriptional activation is unclear. To this end, we expressed Atf1 phosphorylation mutants from a constitutive promoter to uncouple Atf1 activity from endogenous, stress-activated Atf1 expression. We found that cells expressing a nonphosphorylatable Atf1 variant are sensitive to oxidative stress because of impaired transcription of a subset of stress genes whose expression is also controlled by another transcription factor, Pap1. Furthermore, cells expressing a phospho-mimicking Atf1 mutant display enhanced stress resistance, and although expression of the Pap1-dependent genes still relied on stress induction, another subset of stress-responsive genes was constitutively expressed in these cells. We also observed that, in cells expressing the phospho-mimicking Atf1 mutant, the presence of Sty1 was completely dispensable, with all stress defects of Sty1-deficient cells being suppressed by expression of the Atf1 mutant. We further demonstrated that Sty1-mediated Atf1 phosphorylation does not stimulate binding of Atf1 to DNA but, rather, establishes a platform of interactions with the basal transcriptional machinery to facilitate transcription initiation. In summary, our results provide evidence that Atf1 phosphorylation by the MAPK Sty1 is required for oxidative stress responses in fission yeast cells by promoting transcription initiation. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

ONC201 kills solid tumor cells by triggering an integrated stress response dependent on ATF4 activation by specific eIF2α kinases.

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Kline, C Leah B; Van den Heuvel, A Pieter J; Allen, Joshua E; Prabhu, Varun V; Dicker, David T; El-Deiry, Wafik S

2016-02-16

ONC201 (also called TIC10) is a small molecule that inactivates the cell proliferation- and cell survival-promoting kinases Akt and ERK and induces cell death through the proapoptotic protein TRAIL. ONC201 is currently in early-phase clinical testing for various malignancies. We found through gene expression and protein analyses that ONC201 triggered an increase in TRAIL abundance and cell death through an integrated stress response (ISR) involving the transcription factor ATF4, the transactivator CHOP, and the TRAIL receptor DR5. ATF4 was not activated in ONC201-resistant cancer cells, and in ONC201-sensitive cells, knockdown of ATF4 or CHOP partially abrogated ONC201-induced cytotoxicity and diminished the ONC201-stimulated increase in DR5 abundance. The activation of ATF4 in response to ONC201 required the kinases HRI and PKR, which phosphorylate and activate the translation initiation factor eIF2α. ONC201 rapidly triggered cell cycle arrest, which was associated with decreased abundance of cyclin D1, decreased activity of the kinase complex mTORC1, and dephosphorylation of the retinoblastoma (Rb) protein. The abundance of X-linked inhibitor of apoptosis protein (XIAP) negatively correlated with the extent of apoptosis in response to ONC201. These effects of ONC201 were independent of whether cancer cells had normal or mutant p53. Thus, ONC201 induces cell death through the coordinated induction of TRAIL by an ISR pathway. Copyright © 2016, American Association for the Advancement of Science.

Down-regulation of ATF2 in the inhibition of T-2-toxin-induced chondrocyte apoptosis by selenium chondroitin sulfate nanoparticles

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Han, Jing; Guo, Xiong

2013-12-01

Selenium chondroitin sulfate nanoparticles (SeCS) with a size range of 30-200 nm were obtained in our previous study. Meanwhile, the up-regulated expression of ATF2 mRNA and protein levels could be observed in the cartilage from Kashin-Beck disease (KBD) patients. In this paper, we investigated the inhibition effect of SeCS on T-2-toxin-induced apoptosis of chondrocyte from KBD patients. Here, we found that when the chondrocytes were treated with T-2 toxin, the chondrocyte apoptosis performed in a concentration-dependent manner. The apoptosis of chondrocyte induced by T-2 toxin involved the increased levels of ATF2, JNK and p38 mRNAs and related protein expression. SeCS could partly block the T-2-toxin-induced chondrocyte apoptosis by decreasing the expression of ATF2, JNK and p38 mRNAs and p-JNK, p-38, ATF2 and p-ATF2 proteins. JNK and p38 pathways involved in the apoptosis of chondrocyte induced by T-2 toxin, and SeCS was efficient in the inhibition of chondrocyte apoptosis by T-2 toxin. These results suggested that SeCS had a potential for further prevention and treatment for KBD as well as other selenium deficiency disease.

Functional analysis of atfA gene to stress response in pathogenic thermal dimorphic fungus Penicillium marneffei.

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Panjaphorn Nimmanee

Full Text Available Penicillium marneffei, the pathogenic thermal dimorphic fungus is a causative agent of a fatal systemic disease, penicilliosis marneffei, in immunocompromised patients especially HIV patients. For growth and survival, this fungus has to adapt to environmental stresses outside and inside host cells and this adaptation requires stress signaling pathways and regulation of gene expression under various kinds of stresses. In this report, P. marneffei activating transcription factor (atfA gene encoding bZip-type transcription factor was characterized. To determine functions of this gene, atfA isogenic mutant strain was constructed using the modified split marker recombination method. The phenotypes and susceptibility to varieties of stresses including osmotic, oxidative, heat, UV, cell wall and cell membrane stresses of the mutant strain were compared with the wild type and the atfA complemented strains. Results demonstrated that the mRNA expression level of P. marneffei atfA gene increased under heat stress at 42°C. The atfA mutant was more sensitive to sodium dodecyl sulphate, amphotericin B and tert-butyl hydroperoxide than the wild type and complemented strains but not hydrogen peroxide, menadione, NaCl, sorbitol, calcofluor white, itraconazole, UV stresses and heat stress at 39°C. In addition, recovery of atfA mutant conidia after mouse and human macrophage infections was significantly decreased compared to those of wild type and complemented strains. These results indicated that the atfA gene was required by P. marneffei under specific stress conditions and might be necessary for fighting against host immune cells during the initiation of infection.

ATF6α/β-mediated adjustment of ER chaperone levels is essential for development of the notochord in medaka fish.

Science.gov (United States)

Ishikawa, Tokiro; Okada, Tetsuya; Ishikawa-Fujiwara, Tomoko; Todo, Takeshi; Kamei, Yasuhiro; Shigenobu, Shuji; Tanaka, Minoru; Saito, Taro L; Yoshimura, Jun; Morishita, Shinichi; Toyoda, Atsushi; Sakaki, Yoshiyuki; Taniguchi, Yoshihito; Takeda, Shunichi; Mori, Kazutoshi

2013-05-01

ATF6α and ATF6β are membrane-bound transcription factors activated by regulated intramembrane proteolysis in response to endoplasmic reticulum (ER) stress to induce various ER quality control proteins. ATF6α- and ATF6β single-knockout mice develop normally, but ATF6α/β double knockout causes embryonic lethality, the reason for which is unknown. Here we show in medaka fish that ATF6α is primarily responsible for transcriptional induction of the major ER chaperone BiP and that ATF6α/β double knockout, but not ATF6α- or ATF6β single knockout, causes embryonic lethality, as in mice. Analyses of ER stress reporters reveal that ER stress occurs physiologically during medaka early embryonic development, particularly in the brain, otic vesicle, and notochord, resulting in ATF6α- and ATF6β-mediated induction of BiP, and that knockdown of the α1 chain of type VIII collagen reduces such ER stress. The absence of transcriptional induction of several ER chaperones in ATF6α/β double knockout causes more profound ER stress and impaired notochord development, which is partially rescued by overexpression of BiP. Thus ATF6α/β-mediated adjustment of chaperone levels to increased demands in the ER is essential for development of the notochord, which synthesizes and secretes large amounts of extracellular matrix proteins to serve as the body axis before formation of the vertebra.

ATF3 inhibits adipocyte differentiation of 3T3-L1 cells

International Nuclear Information System (INIS)

Jang, Min Kyung; Kim, Cho Hee; Seong, Je Kyung; Jung, Myeong Ho

2012-01-01

Highlights: ► Overexpression of ATF3 inhibits adipocyte differentiation in 3T3-L1 cells. ► Overexpression of ATF3 represses C/EBPα expression. ► ATF3 directly binds to mouse C/EBPα promoter spanning from −1928 to −1907. ► ATF3 may play a role in hypoxia-mediated inhibition of adipocyte differentiation. -- Abstract: ATF3 is a stress-adaptive gene that regulates proliferation or apoptosis under stress conditions. However, the role of ATF3 is unknown in adipocyte cells. Therefore, in this study, we investigated the functional role of ATF3 in adipocytes. Both lentivirus-mediated overexpression of ATF3 and stably-overexpressed ATF3 inhibited adipocyte differentiation in 3T3-L1 cells, as revealed by decreased lipid staining with oil red staining and reduction in adipogenic genes. Thapsigargin treatment and overexpression of ATF3 decreased C/EBPα transcript and repressed the activity of the 3.6-kb mouse C/EBPα promoter, demonstrating that ATF3 downregulates C/EBPα expression. Transfection studies using mutant constructs containing 5′-deletions in the C/EBPα promoter revealed that a putative ATF/CRE element, GGATGTCA, is located between −1921 and −1914. Electrophoretic mobility shift assay and chromatin immunoprecipitation assay demonstrated that ATF3 directly binds to mouse C/EBPα promoter spanning from −1928 to −1907. Both chemical hypoxia-mimetics or physical hypoxia led to reduce the C/EBPα mRNA and repress the promoter activity of the C/EBPα gene, whereas increase ATF3 mRNA, suggesting that ATF3 may contribute to the inhibition of adipocyte differentiation in hypoxia through downregulation of C/EBPα expression. Collectively, these results demonstrate that ATF3 represses the C/EBPα gene, resulting in inhibition of adipocyte differentiation, and thus plays a role in hypoxia-mediated inhibition of adipocyte differentiation.

Upregulation of the coagulation factor VII gene during glucose deprivation is mediated by activating transcription factor 4.

Science.gov (United States)

Cronin, Katherine R; Mangan, Thomas P; Carew, Josephine A

2012-01-01

Constitutive production of blood coagulation proteins by hepatocytes is necessary for hemostasis. Stressful conditions trigger adaptive cellular responses and delay processing of most proteins, potentially affecting plasma levels of proteins secreted exclusively by hepatocytes. We examined the effect of glucose deprivation on expression of coagulation proteins by the human hepatoma cell line, HepG2. Expression of coagulation factor VII, which is required for initiation of blood coagulation, was elevated by glucose deprivation, while expression of other coagulation proteins decreased. Realtime PCR and ELISA demonstrated that the relative percentage expression +/- SD of steady-state F7 mRNA and secreted factor VII antigen were significantly increased (from 100+/-15% to 188+/-27% and 100+/-8.8% to 176.3+/-17.3% respectively, pfactor ATF4 and of additional stress-responsive genes. Small interfering RNAs directed against ATF4 potently reduced basal F7 expression, and prevented F7 upregulation by glucose deprivation. The response of the endogenous F7 gene was replicated in reporter gene assays, which further indicated that ATF4 effects were mediated via interaction with an amino acid response element in the F7 promoter. Our data indicated that glucose deprivation enhanced F7 expression in a mechanism reliant on prior ATF4 upregulation primarily due to increased transcription from the ATF4 gene. Of five coagulation protein genes examined, only F7 was upregulated, suggesting that its functions may be important in a systemic response to glucose deprivation stress.

Upregulation of the coagulation factor VII gene during glucose deprivation is mediated by activating transcription factor 4.

Directory of Open Access Journals (Sweden)

Katherine R Cronin

Full Text Available BACKGROUND: Constitutive production of blood coagulation proteins by hepatocytes is necessary for hemostasis. Stressful conditions trigger adaptive cellular responses and delay processing of most proteins, potentially affecting plasma levels of proteins secreted exclusively by hepatocytes. We examined the effect of glucose deprivation on expression of coagulation proteins by the human hepatoma cell line, HepG2. METHODOLOGY/PRINCIPAL FINDINGS: Expression of coagulation factor VII, which is required for initiation of blood coagulation, was elevated by glucose deprivation, while expression of other coagulation proteins decreased. Realtime PCR and ELISA demonstrated that the relative percentage expression +/- SD of steady-state F7 mRNA and secreted factor VII antigen were significantly increased (from 100+/-15% to 188+/-27% and 100+/-8.8% to 176.3+/-17.3% respectively, p<0.001 at 24 hr of treatment. The integrated stress response was induced, as indicated by upregulation of transcription factor ATF4 and of additional stress-responsive genes. Small interfering RNAs directed against ATF4 potently reduced basal F7 expression, and prevented F7 upregulation by glucose deprivation. The response of the endogenous F7 gene was replicated in reporter gene assays, which further indicated that ATF4 effects were mediated via interaction with an amino acid response element in the F7 promoter. CONCLUSIONS/SIGNIFICANCE: Our data indicated that glucose deprivation enhanced F7 expression in a mechanism reliant on prior ATF4 upregulation primarily due to increased transcription from the ATF4 gene. Of five coagulation protein genes examined, only F7 was upregulated, suggesting that its functions may be important in a systemic response to glucose deprivation stress.

ATF [Advanced Toroidal Facility] data management

International Nuclear Information System (INIS)

Kannan, K.L.; Baylor, L.R.

1988-01-01

Data management for the Advanced Toroidal Facility (ATF), a stellarator located at Oak Ridge National Laboratory (ORNL), is provided by DMG, a locally developed, VAX-based software system. DMG is a data storage and retrieval software system that provides the user interface to ATF raw and analyzed data. Data are described in terms of data models and data types and are organized as signals into files, which are internally documented. The system was designed with user accessibility, software maintainability, and extensibility as primary goals. Extensibility features include compatibility with ATF as it moves from pulsed to steady-state operation and capability for use of the DMG system with experiments other than ATF. DMG is implemented as a run-time library of routines available as a shareable image. General-purpose and specialized data acquisition and analysis applications have been developed using the DMG system. This paper describes the DMG system and the interfaces to it. 4 refs., 2 figs

A superconducting magnet upgrade of the ATF2 final focus

CERN Document Server

Parker, B; Escallier, J; He, P; Jain, P; Marone, A; Wanderer, P; Wu, KC; Hauviller, C; Marin, E; Tomas, R; Zimmermann, F; Bolzon, B; Jeremie, A; Kimura, N; Kubo, K; Kume, T; Kuroda, S; Okugi, T; Tauchi, T; Terunuma, N; Tomaru, T; Tsuchiya, K; Urakawa, J; Yamamoto, A; Bambade, P; Coe, P; Urner, D; Seryi, A; Spencer, C; White, G

2010-01-01

The ATF2 facility at KEK is a proving ground for linear collider technology with a well instrumented extracted beam line and Final Focus (FF). The primary ATF2 goal is to demonstrate the extreme beam demagnification and spot stability needed for a linear collider FF [1]. But the ATF2 FF uses water cooled magnets and the ILC baseline has a superconducting (SC) FF [2]. We plan to upgrade ATF2 and replace some of the warm FF magnets with SC FF magnets. The ATF2 SC magnets, like the ILC FF, will made via direct wind construction [3]. ATF2 coil winding is in progress at BNL and warm magnetic measurements indicate we have achieved good field quality. Studies indicate that having ATF2 FF magnets with larger aperture and better field quality should allow reducing the ATF2 FF beta function for study of focusing regimes relevant to CLIC [4]. The ATF2 magnet cryostat will have laser view ports for directly monitoring cold mass movement. We plan to make stability measurements at BNL and KEK to relate ATF2 FF magnet perfo...

ATF4 induction through an atypical integrated stress response to ONC201 triggers p53-independent apoptosis in hematological malignancies.

Science.gov (United States)

Ishizawa, Jo; Kojima, Kensuke; Chachad, Dhruv; Ruvolo, Peter; Ruvolo, Vivian; Jacamo, Rodrigo O; Borthakur, Gautam; Mu, Hong; Zeng, Zhihong; Tabe, Yoko; Allen, Joshua E; Wang, Zhiqiang; Ma, Wencai; Lee, Hans C; Orlowski, Robert; Sarbassov, Dos D; Lorenzi, Philip L; Huang, Xuelin; Neelapu, Sattva S; McDonnell, Timothy; Miranda, Roberto N; Wang, Michael; Kantarjian, Hagop; Konopleva, Marina; Davis, R Eric; Andreeff, Michael

2016-02-16

The clinical challenge posed by p53 abnormalities in hematological malignancies requires therapeutic strategies other than standard genotoxic chemotherapies. ONC201 is a first-in-class small molecule that activates p53-independent apoptosis, has a benign safety profile, and is in early clinical trials. We found that ONC201 caused p53-independent apoptosis and cell cycle arrest in cell lines and in mantle cell lymphoma (MCL) and acute myeloid leukemia (AML) samples from patients; these included samples from patients with genetic abnormalities associated with poor prognosis or cells that had developed resistance to the nongenotoxic agents ibrutinib and bortezomib. Moreover, ONC201 caused apoptosis in stem and progenitor AML cells and abrogated the engraftment of leukemic stem cells in mice while sparing normal bone marrow cells. ONC201 caused changes in gene expression similar to those caused by the unfolded protein response (UPR) and integrated stress responses (ISRs), which increase the translation of the transcription factor ATF4 through an increase in the phosphorylation of the translation initiation factor eIF2α. However, unlike the UPR and ISR, the increase in ATF4 abundance in ONC201-treated hematopoietic cells promoted apoptosis and did not depend on increased phosphorylation of eIF2α. ONC201 also inhibited mammalian target of rapamycin complex 1 (mTORC1) signaling, likely through ATF4-mediated induction of the mTORC1 inhibitor DDIT4. Overexpression of BCL-2 protected against ONC201-induced apoptosis, and the combination of ONC201 and the BCL-2 antagonist ABT-199 synergistically increased apoptosis. Thus, our results suggest that by inducing an atypical ISR and p53-independent apoptosis, ONC201 has clinical potential in hematological malignancies. Copyright © 2016, American Association for the Advancement of Science.

Cyclin D3 interacts with human activating transcription factor 5 and potentiates its transcription activity

International Nuclear Information System (INIS)

Liu Wenjin; Sun Maoyun; Jiang Jianhai; Shen Xiaoyun; Sun Qing; Liu Weicheng; Shen Hailian; Gu Jianxin

2004-01-01

The Cyclin D3 protein is a member of the D-type cyclins. Besides serving as cell cycle regulators, D-type cyclins have been reported to be able to interact with several transcription factors and modulate their transcriptional activations. Here we report that human activating transcription factor 5 (hATF5) is a new interacting partner of Cyclin D3. The interaction was confirmed by in vivo coimmunoprecipitation and in vitro binding analysis. Neither interaction between Cyclin D1 and hATF5 nor interaction between Cyclin D2 and hATF5 was observed. Confocal microscopy analysis showed that Cyclin D3 could colocalize with hATF5 in the nuclear region. Cyclin D3 could potentiate hATF5 transcriptional activity independently of its Cdk4 partner. But Cyclin D1 and Cyclin D2 had no effect on hATF5 transcriptional activity. These data provide a new clue to understand the new role of Cyclin D3 as a transcriptional regulator

ATF data management

International Nuclear Information System (INIS)

Kannan, K.L.; Baylor, L.R.

1988-01-01

Data management for the Advanced Toroidal Facility (ATF), a stellarator located at Oak Ridge National Laboratory, is provided by DMG, a locally developed, VAX-based software system. DMG is a data storage and retrieval software system that provides the user interface to ATF raw and analyzed data. Data are described in terms of data models and data types and are organized as signals into files, which are internally documented. The system was designed with user accessibility, software maintainability, and extensibility as primary goals. Extensibility features include compatibility with ATF as it moves from pulsed to steady-state operation and capability for use of the DMG system with experiments other than ATF. DMG is implemented as a run-time library of routines available as a shareable image. General-purpose and specialized data acquisition and analysis applications have been developed using the DMG system. This article describes the DMG system and the interfaces to it

ATF2 Proposal v. 2

CERN Document Server

Grishanov, B I; Alabau-Pons, M; Angal-Kalinin, Deepa; Appleby, R; Araki, S; Bailey, I; Bambade, P; Bane, Karl Leopold Freitag; Barlow, R; Blair, G A; Bolzon, B; Boorman, G; Bosco, A; Brachmann, A; Braun, Hans Heinrich; Burrows, P N; Carter, J; Choi, J; Christian, Glenn B; Clarke, C; Dabiri-Khah, A; Dadoun, O; Danagulyan, S; Delerue, N; Dixit, S; Driouichi, C; Elsen E; Gao, J; Geffroy, N; Gronberg, J; Hartin, Anthony F; Hayano, H; Higashi, Y; Himel, T; Honda, Y; Howell, D; Huang, J Y; Iwashita, Y; Jenner, L; Jones, J; Jones, R; Jérémie, A; Kalinin, A; Kanazawa, K; Kang, H S; Karyotakis, Yu; Kim, E S; Kim, S; Komamiya, S; Kourevlev, German Yu; Kubo, K; Kumada, M; Kume, T; Kuriki, M; Kuroda, S; Liu, W; Logatchev, P V; Lyapin, A; Malton, S; Markiewicz, T W; Masuzawa, M; Mihara, T; Miller, D J; Molloy, S; Mtingwa, S; Naito, T; Nan-Phinney, Y; Napoly, O; Nelson, J; Okugi, T; Payet, J; Pei, G X; Pivi, M T F; Podgorny, F; Price, M; Raubenheimer, T O; Reichold, A; Ross, M; Sanuki, T; Schulte, Daniel; Seryi, R A; Solyak, N; Soo Ko In; Spencer, C M; Suehara, T; Sugahara, R; Takahashi, T; Takashi-Boogert, S; Tauchi, T; Telnov, Valery I; Tenenbaum, P G; Terunuma, N; Toge, N; Torrence, E; Urakawa, J; Urner, D; Vogel, V; Walker, N; Wang, J Q; Wendt, M; White, G; Wing, M; Wolski, A; Woodley, M; Yamaoka, H; Yokoya, K; Zimmermann, Frank

2006-01-01

For achieving the high luminosity required at the International Linear Collider (ILC), it is critical to focus the beams to nanometer size with the ILC Beam Delivery System (BDS), and to maintain the beam collision with a nanometer-scale stability. To establish the technologies associated with this ultra-high precision beam handling, it has been proposed to implement an ILC-like final focus optics in an extension of the existing extraction beamline of ATF at KEK. The ATF is considered to be the best platform for this exercise, since it provides an adequate ultra-low emittance electron beam in a manner dedicated to the development of ILC. The two major goals for this facility, called ATF2, are : (A) Achievement of a 37 nm beam size, and (B) control of beam position down to 2 nm level. The scientific justification for the ATF2 project and its technical design have been described in Volume 1 of the ATF2 Proposal [1]. We present here Volume 2 of the ATF2 Proposal, in which we present specifics of the construction...

Adenoviral gene transfer of angiostatic ATF-BPTI inhibits tumour growth

International Nuclear Information System (INIS)

Lefesvre, Pierre; Attema, Joline; Bekkum, Dirk van

2002-01-01

The outgrowth of new vessels – angiogenesis – in the tumour mass is considered to be a limiting factor of tumour growth. To inhibit the matrix lysis that is part of the tumour angiogenesis, we employed the chimeric protein mhATF-BPTI, composed of the receptor binding part of the urokinase (ATF) linked to an inhibitor of plasmin (BPTI). For delivery, recombinant adenovirus encoding the transgene of interest was injected intravenously or locally into the tumour. The anti tumour effect of this compound was compared to that of human endostatin and of mhATF alone in two different rat bronchial carcinomas growing either as subcutaneous implants or as metastases. Significant inhibition of the tumour growth and decrease of the number of lung metastasis was achieved when the concentration of mhATF-BPTI at the tumour site was above 400 of ng / g tissue. This concentration could be achieved via production by the liver, only if permissive to the recombinant adenovirus. When the tumour cells could be transduced, local delivery of the vector was enough to obtain a response. In the case of metastasis, the capacity of the lung tissue to concentrate the encoded protein was essential to reach the required therapeutic levels. Further, endostatin or mhATF could not reproduce the effects of mhATF-BPTI, at similar concentrations (mhATF) and even at 10-fold higher concentration (endostatin). The ATF-BPTI was shown to inhibit tumour growth of different rat lung tumours when critical concentration was reached. In these tumour models, endostatin or ATF induce almost no tumour response

Activating Transcription Factor 3 Regulates Immune and Metabolic Homeostasis

Science.gov (United States)

Rynes, Jan; Donohoe, Colin D.; Frommolt, Peter; Brodesser, Susanne; Jindra, Marek

2012-01-01

Integration of metabolic and immune responses during animal development ensures energy balance, permitting both growth and defense. Disturbed homeostasis causes organ failure, growth retardation, and metabolic disorders. Here, we show that the Drosophila melanogaster activating transcription factor 3 (Atf3) safeguards metabolic and immune system homeostasis. Loss of Atf3 results in chronic inflammation and starvation responses mounted primarily by the larval gut epithelium, while the fat body suffers lipid overload, causing energy imbalance and death. Hyperactive proinflammatory and stress signaling through NF-κB/Relish, Jun N-terminal kinase, and FOXO in atf3 mutants deregulates genes important for immune defense, digestion, and lipid metabolism. Reducing the dose of either FOXO or Relish normalizes both lipid metabolism and gene expression in atf3 mutants. The function of Atf3 is conserved, as human ATF3 averts some of the Drosophila mutant phenotypes, improving their survival. The single Drosophila Atf3 may incorporate the diversified roles of two related mammalian proteins. PMID:22851689

Activating transcription factor 3 regulates immune and metabolic homeostasis.

Science.gov (United States)

Rynes, Jan; Donohoe, Colin D; Frommolt, Peter; Brodesser, Susanne; Jindra, Marek; Uhlirova, Mirka

2012-10-01

Integration of metabolic and immune responses during animal development ensures energy balance, permitting both growth and defense. Disturbed homeostasis causes organ failure, growth retardation, and metabolic disorders. Here, we show that the Drosophila melanogaster activating transcription factor 3 (Atf3) safeguards metabolic and immune system homeostasis. Loss of Atf3 results in chronic inflammation and starvation responses mounted primarily by the larval gut epithelium, while the fat body suffers lipid overload, causing energy imbalance and death. Hyperactive proinflammatory and stress signaling through NF-κB/Relish, Jun N-terminal kinase, and FOXO in atf3 mutants deregulates genes important for immune defense, digestion, and lipid metabolism. Reducing the dose of either FOXO or Relish normalizes both lipid metabolism and gene expression in atf3 mutants. The function of Atf3 is conserved, as human ATF3 averts some of the Drosophila mutant phenotypes, improving their survival. The single Drosophila Atf3 may incorporate the diversified roles of two related mammalian proteins.

Analysis list: Atf3 [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Atf3 Blood,Pancreas + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Atf3.1.tsv http:...//dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Atf3.5.tsv http://dbarchive.biosciencedbc.jp/k...yushu-u/mm9/target/Atf3.10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Atf3.Blood.tsv,http://dba...rchive.biosciencedbc.jp/kyushu-u/mm9/colo/Atf3.Pancreas.tsv http://dbarchive.bios...ciencedbc.jp/kyushu-u/mm9/colo/Blood.gml,http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Pancreas.gml ...

CAVITY BEAM POSITION MONITOR SYSTEM FOR ATF2

CERN Document Server

Boogert, S T; Cullinan, F; Joshi, N; Lyapin, A; Aryshev, A; Honda, Y; Naito, T; Terunuma, N; Urakara, J; Heo, A; Kim, E-S; Kim, Y I; McCormick, D; Frisch, J; Nelson, J; Smith, T; White, G R

2011-01-01

The Accelerator Test Facility 2 (ATF2) in KEK, Japan, is a prototype scaled demonstrator system for the final focus required for a future high energy lepton linear collider. The ATF2 beam-line is instrumented with a total of 41 high resolution C and S band resonant cavity beam position monitors (BPM) with associated mixer electronics and digitisers. In addition 4 high resolution BPMs have been recently installed at the interaction point, we briefly describe the first operational experience of these cavities in the ATF2 beam-line. The current status of the overall BPM system is also described, with a focus on operational techniques and performance.

Mitochondrial dysfunction enhances cisplatin resistance in human gastric cancer cells via the ROS-activated GCN2-eIF2α-ATF4-xCT pathway.

Science.gov (United States)

Wang, Sheng-Fan; Chen, Meng-Shian; Chou, Yueh-Ching; Ueng, Yune-Fang; Yin, Pen-Hui; Yeh, Tien-Shun; Lee, Hsin-Chen

2016-11-08

Mitochondrial DNA mutations and defects in mitochondrial enzymes have been identified in gastric cancers, and they might contribute to cancer progression. In previous studies, mitochondrial dysfunction was induced by oligomycin-enhanced chemoresistance to cisplatin. Herein, we dissected the regulatory mechanism for mitochondrial dysfunction-enhanced cisplatin resistance in human gastric cancer cells. Repeated cisplatin treatment-induced cisplatin-resistant cells exhibited high SLC7A11 (xCT) expression, and xCT inhibitors (sulfasalazine or erastin), xCT siRNA, or a GSH synthesis inhibitor (buthionine sulphoximine, BSO) could sensitize these cells to cisplatin. Clinically, the high expression of xCT was associated with a poorer prognosis for gastric cancer patients under adjuvant chemotherapy. Moreover, we found that mitochondrial dysfunction enhanced cisplatin resistance and up-regulated xCT expression, as well as intracellular glutathione (GSH). The xCT inhibitors, siRNA against xCT or BSO decreased mitochondrial dysfunction-enhanced cisplatin resistance. We further demonstrated that the upregulation of the eIF2α-ATF4 pathway contributed to mitochondrial dysfunction-induced xCT expression, and activated eIF2α kinase GCN2, but not PERK, stimulated the eIF2α-ATF4-xCT pathway in response to mitochondrial dysfunction-increased reactive oxygen species (ROS) levels. In conclusion, our results suggested that the ROS-activated GCN2-eIF2α-ATF4-xCT pathway might contribute to mitochondrial dysfunction-enhanced cisplatin resistance and could be a potential target for gastric cancer therapy.

ATF1 and RAS in exosomes are potential clinical diagnostic markers for cervical cancer.

Science.gov (United States)

Shi, Yanhua; Wang, Wei; Yang, Baozhi; Tian, Hongge

2017-10-01

Cervical cancer is one of the most common cancers among women worldwide. It is highly lethal yet can be treated when found in early stage. Thus, early detection is of significant important for early diagnosis of cervical cancer. Exosomes have been used as biomarkers in clinical diagnosis. It is unknown that whether blood exosomes associated with cervical cancer can be detected and if these exosomes can accurately represent the developmental stage of cervical cancer. Mouse models were made out of a relapsed cervical cancer patient's tumour sample for original and recurrent cervical cancer, and gene analysis in both tumours and exosomes in these mouse models were performed. We found that activating transcription factor 1 (ATF1) and RAS genes were significantly up-regulated in tumours of both primary and recurrent cervical cancer mouse model, and they can also be detected in the blood exosomes of the mouse model. Our results indicated that ATF1 and RAS could be potential candidate biomarkers for cervical cancer in early diagnosis. ATF1 and RAS genes were found significantly elevated in tumours of primary and recurrent cervical cancer mouse model, and they were also detected in the blood exosomes. Therefore, ATF1 and RAS could be used as a diagnostic marker for cervical cancer in the future. Copyright © 2017 John Wiley & Sons, Ltd.

Frontline Science: ATF3 is responsible for the inhibition of TNF-α release and the impaired migration of acute ethanol-exposed monocytes and macrophages.

Science.gov (United States)

Hu, Chaojie; Meng, Xiaoming; Huang, Cheng; Shen, Chenlin; Li, Jun

2017-03-01

Binge drinking represses host innate immunity and leads to a high risk of infection. Acute EtOH-pretreated macrophages exhibit a decreased production of proinflammatory mediators in response to LPS. ATF3 is induced and counter-regulates the LPS/TLR4 inflammatory cascade. Here, we investigated the potential role of ATF3 in LPS tolerance in acute ethanol-pretreated macrophages. We found that there was an inverse correlation between ATF3 and LPS-induced TNF-α production in acute ethanol-pretreated murine monocytes and macrophages. The knockdown of ATF3 attenuated the inhibitory effects of acute ethanol treatment on LPS-induced TNF-α production. Furthermore, ChIP assays and co-IP demonstrated that ATF3, together with HDAC1, negatively modulated the transcription of TNF-α. In binge-drinking mice challenged with LPS, an up-regulation of ATF3 and HDAC1 and a concomitant decrease in TNF-α were observed. Given that HDAC1 was concomitantly induced in acute ethanol-exposed monocytes and macrophages, we used the HDACi TSA or silenced HDAC1 to explore the role of HDAC1 in acute ethanol-treated macrophages. Our results revealed that TSA treatment and HDAC1 knockdown prevented acute ethanol-induced ATF3 expression and the inhibition of TNF-α transcription. These data indicated a dual role for HDAC1 in acute ethanol-induced LPS tolerance. Furthermore, we showed that the induction of ATF3 led to the impaired migration of BM monocytes and macrophages. Overall, we present a novel role for ATF3 in the inhibition of LPS-induced TNF-α and in the impairment of monocyte and macrophage migration. © Society for Leukocyte Biology.

The response of the prostate to circulating cholesterol: activating transcription factor 3 (ATF3 as a prominent node in a cholesterol-sensing network.

Directory of Open Access Journals (Sweden)

Jayoung Kim

Full Text Available Elevated circulating cholesterol is a systemic risk factor for cardiovascular disease and metabolic syndrome, however the manner in which the normal prostate responds to variations in cholesterol levels is poorly understood. In this study we addressed the molecular and cellular effects of elevated and suppressed levels of circulating cholesterol on the normal prostate. Integrated bioinformatic analysis was performed using DNA microarray data from two experimental formats: (1 ventral prostate from male mice with chronically elevated circulating cholesterol and (2 human prostate cells exposed acutely to cholesterol depletion. A cholesterol-sensitive gene expression network was constructed from these data and the transcription factor ATF3 was identified as a prominent node in the network. Validation experiments confirmed that elevated cholesterol reduced ATF3 expression and enhanced proliferation of prostate cells, while cholesterol depletion increased ATF3 levels and inhibited proliferation. Cholesterol reduction in vivo alleviated dense lymphomononuclear infiltrates in the periprostatic adipose tissue, which were closely associated with nerve tracts and blood vessels. These findings open new perspectives on the role of cholesterol in prostate health, and provide a novel role for ATF3, and associated proteins within a large signaling network, as a cholesterol-sensing mechanism.

ATF3 upregulation in glia during Wallerian degeneration: differential expression in peripheral nerves and CNS white matter

Directory of Open Access Journals (Sweden)

Coffin Robert S

2004-03-01

Full Text Available Abstract Background Many changes in gene expression occur in distal stumps of injured nerves but the transcriptional control of these events is poorly understood. We have examined the expression of the transcription factors ATF3 and c-Jun by non-neuronal cells during Wallerian degeneration following injury to sciatic nerves, dorsal roots and optic nerves of rats and mice, using immunohistochemistry and in situ hybridization. Results Following sciatic nerve injury – transection or transection and reanastomosis – ATF3 was strongly upregulated by endoneurial, but not perineurial cells, of the distal stumps of the nerves by 1 day post operation (dpo and remained strongly expressed in the endoneurium at 30 dpo when axonal regeneration was prevented. Most ATF3+ cells were immunoreactive for the Schwann cell marker, S100. When the nerve was transected and reanastomosed, allowing regeneration of axons, most ATF3 expression had been downregulated by 30 dpo. ATF3 expression was weaker in the proximal stumps of the injured nerves than in the distal stumps and present in fewer cells at all times after injury. ATF3 was upregulated by endoneurial cells in the distal stumps of injured neonatal rat sciatic nerves, but more weakly than in adult animals. ATF3 expression in transected sciatic nerves of mice was similar to that in rats. Following dorsal root injury in adult rats, ATF3 was upregulated in the part of the root between the lesion and the spinal cord (containing Schwann cells, beginning at 1 dpo, but not in the dorsal root entry zone or in the degenerating dorsal column of the spinal cord. Following optic nerve crush in adult rats, ATF3 was found in some cells at the injury site and small numbers of cells within the optic nerve displayed weak immunoreactivity. The pattern of expression of c-Jun in all types of nerve injury was similar to that of ATF3. Conclusion These findings raise the possibility that ATF3/c-Jun heterodimers may play a role in

Transcriptome-Based Modeling Reveals that Oxidative Stress Induces Modulation of the AtfA-Dependent Signaling Networks in Aspergillus nidulans

Directory of Open Access Journals (Sweden)

Erzsébet Orosz

2017-01-01

Full Text Available To better understand the molecular functions of the master stress-response regulator AtfA in Aspergillus nidulans, transcriptomic analyses of the atfA null mutant and the appropriate control strains exposed to menadione sodium bisulfite- (MSB-, t-butylhydroperoxide- and diamide-induced oxidative stresses were performed. Several elements of oxidative stress response were differentially expressed. Many of them, including the downregulation of the mitotic cell cycle, as the MSB stress-specific upregulation of FeS cluster assembly and the MSB stress-specific downregulation of nitrate reduction, tricarboxylic acid cycle, and ER to Golgi vesicle-mediated transport, showed AtfA dependence. To elucidate the potential global regulatory role of AtfA governing expression of a high number of genes with very versatile biological functions, we devised a model based on the comprehensive transcriptomic data. Our model suggests that an important function of AtfA is to modulate the transduction of stress signals. Although it may regulate directly only a limited number of genes, these include elements of the signaling network, for example, members of the two-component signal transduction systems. AtfA acts in a stress-specific manner, which may increase further the number and diversity of AtfA-dependent genes. Our model sheds light on the versatility of the physiological functions of AtfA and its orthologs in fungi.

Pharmacologic inhibition of S1P attenuates ATF6 expression, causes ER stress and contributes to apoptotic cell death.

Science.gov (United States)

Lebeau, Paul; Byun, Jae Hyun; Yousof, Tamana; Austin, Richard C

2018-04-22

Mammalian cells express unique transcription factors embedded in the endoplasmic reticulum (ER) membrane, such as the sterol regulatory element-binding proteins (SREBPs), that promote de novo lipogenesis. Upon their release from the ER, the SREBPs require proteolytic activation in the Golgi by site-1-protease (S1P). As such, inhibition of S1P, using compounds such as PF-429242 (PF), reduces cholesterol synthesis and may represent a new strategy for the management of dyslipidemia. In addition to the SREBPs, the unfolded protein response (UPR) transducer, known as the activating transcription factor 6 (ATF6), is another ER membrane-bound transcription factor that requires S1P-mediated activation. ATF6 regulates ER protein folding capacity by promoting the expression of ER chaperones such as the 78-kDa glucose-regulated protein (GRP78). ER-resident chaperones like GRP78 prevent and/or resolve ER polypeptide accumulation and subsequent ER stress-induced UPR activation by folding nascent polypeptides. Here we report that pharmacological inhibition of S1P reduced the expression of ATF6 and GRP78 and induced the activation of UPR transducers inositol-requiring enzyme-1α (IRE1α) and protein kinase RNA-like ER kinase (PERK). As a consequence, S1P inhibition also increased the susceptibility of cells to ER stress-induced cell death. Our findings suggest that S1P plays a crucial role in the regulation of ER folding capacity and also identifies a compensatory cross-talk between UPR transducers in order to maintain adequate ER chaperone expression and activity. Copyright © 2018. Published by Elsevier Inc.

ATF [Advanced Toroidal Facility]-2 studies

International Nuclear Information System (INIS)

Lyon, J.F.; Carreras, B.A.; Dominguez, N.

1989-10-01

Design studies for a low-aspect-ratio, large next-generation stellarator, ATF-II, with high-current-density, high-field, stable NbTi/Cu helical windings are described. The design parameters are an average plasma radius of 0.52 m, a major radius of 2 m, and a field on axis of 4-5 T, with 10 to 15 MW of heating power. Such a device would be comparable in scope to other next-generation stellarators but would have roughly the same aspect ratio as the tokamaks without, however, the need for current drive to sustain steady-state operation. A number of low-aspect-ratio physics issues need to be addressed in the design of ATF-II, primarily compromises between high-beta capability and good confinement properties. A six-field-period Compact Torsatron is chosen as a reference design for ATF-II, and its main features and performance predictions are discussed. An integrated (beta capability and confinement) optimization approach and optimization of superconducting windings are also discussed. 36 refs., 13 figs., 2 tabs

RFX Transcription Factor DAF-19 Regulates 5-HT and Innate Immune Responses to Pathogenic Bacteria in Caenorhabditis elegans

Science.gov (United States)

Choi, Sunju; Xu, Lu; Sze, Ji Ying

2013-01-01

In Caenorhabditis elegans the Toll-interleukin receptor domain adaptor protein TIR-1 via a conserved mitogen-activated protein kinase (MAPK) signaling cascade induces innate immunity and upregulates serotonin (5-HT) biosynthesis gene tph-1 in a pair of ADF chemosensory neurons in response to infection. Here, we identify transcription factors downstream of the TIR-1 signaling pathway. We show that common transcription factors control the innate immunity and 5-HT biosynthesis. We demonstrate that a cysteine to tyrosine substitution in an ARM motif of the HEAT/Arm repeat region of the TIR-1 protein confers TIR-1 hyperactivation, leading to constitutive tph-1 upregulation in the ADF neurons, increased expression of intestinal antimicrobial genes, and enhanced resistance to killing by the human opportunistic pathogen Pseudomonas aeruginosa PA14. A forward genetic screen for suppressors of the hyperactive TIR-1 led to the identification of DAF-19, an ortholog of regulatory factor X (RFX) transcription factors that are required for human adaptive immunity. We show that DAF-19 concerts with ATF-7, a member of the activating transcription factor (ATF)/cAMP response element-binding B (CREB) family of transcription factors, to regulate tph-1 and antimicrobial genes, reminiscent of RFX-CREB interaction in human immune cells. daf-19 mutants display heightened susceptibility to killing by PA14. Remarkably, whereas the TIR-1-MAPK-DAF-19/ATF-7 pathway in the intestinal immunity is regulated by DKF-2/protein kinase D, we found that the regulation of tph-1 expression is independent of DKF-2 but requires UNC-43/Ca2+/calmodulin-dependent protein kinase (CaMK) II. Our results suggest that pathogenic cues trigger a common core-signaling pathway via tissue-specific mechanisms and demonstrate a novel role for RFX factors in neuronal and innate immune responses to infection. PMID:23505381

Damping Wiggler Study at KEK-ATF

CERN Document Server

Naito, Takashi; Honda, Yosuke; Korostelev, Maxim S; Kubo, Kiyoshi; Kuriki, Masao; Kuroda, Shigeru; Muto, Toshiya; Nakamura, Norio; Ross, Marc; Sakai, Hiroshi; Terunuma, Nobuhiro; Urakawa, Junji; Zimmermann, Frank

2005-01-01

The effects by damping wiggler magnets have been studied at KEK-ATF. The damping ring of the KEK-ATF is a 1.3 GeV storage ring capable of producing ultra-low emittance electron beams. It is significant issue to realize fast damping in the damping ring. The tuning method with 4 sets of wiggler was investigated for the ultra-low emittance beam. The performance on the beam quality, which is related to the transverse (x and y) and the longitudinal (z and dp/p), has been measured by the SR monitor, the laser wire, the streak camera and the energy spread monitor at the extraction line. We report on the operation condition and the measurement results.

Bolometric measurements in ATF

International Nuclear Information System (INIS)

Hiroe, S.; Wilgen, J.B.; Batchelor, D.B.; Bigelow, T.S.; Wing, W.R.; Bell, G.L.; Gandy, R.F.; Goldfinger, R.C.; Kindsfather, R.R.

1989-01-01

Bolometer measurements are made under various plasma conditions in ATF. Each bolometer module includes four pairs of detectors; each pair consists of a sensor and a reference detector. Two or three detector pairs in each module were installed with various types of aperture masks to serve as radiation detectors. The rest were completely shielded from plasma emissions and used as blind detectors to measure background levels. When electron cyclotron heating (ECH) power was applied to ATF, the radiation signal was more than 10 times higher than that expected for 100 kW of radiated power. Surprisingly, similar signal levels were observed on the blind detectors. It is hypothesized that the bolometers are sensitive to ECH power at 53 GHz. (This problem may be general in near-term fusion experiments, in which microwave power will be an important tool for plasma heating.) In this paper, experiments aimed at proving this hypothesis are reported; bolometric signals before and after chromium gettering are discussed; and measurements of the microwave power deposition profile around the torus, made by using the observed microwave interference with the blind detectors, are presented. 4 refs., 4 figs

BNL ATF II beamlines design

Energy Technology Data Exchange (ETDEWEB)

Fedurin, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Jing, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Stratakis, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Swinson, C. [Brookhaven National Lab. (BNL), Upton, NY (United States)

2015-05-03

The Brookhaven National Laboratory. Accelerator Test Facility (BNL ATF) is currently undergoing a major upgrade (ATF-II). Together with a new location and much improved facilities, the ATF will see an upgrade in its major capabilities: electron beam energy and quality and CO₂ laser power. The electron beam energy will be increased in stages, first to 100-150 MeV followed by a further increase to 500 MeV. Combined with the planned increase in CO₂ laser power (from 1-100 TW), the ATF-II will be a powerful tool for Advanced Accelerator research. A high-brightness electron beam, produced by a photocathode gun, will be accelerated and optionally delivered to multiple beamlines. Besides the energy range (up to a possible 500 MeV in the final stage) the electron beam can be tailored to each experiment with options such as: small transverse beam size (<10 um), short bunch length (<100 fsec) and, combined short and small bunch options. This report gives a detailed overview of the ATFII capabilities and beamlines configuration.

Experimental approach for adhesion strength of ATF cladding

Energy Technology Data Exchange (ETDEWEB)

Kim, Donghyun; Kim, Hyochan; Yang, Yongsik; In, Wangkee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Haksung [Hanyang University, Seoul (Korea, Republic of)

2016-10-15

The quality of a coating depends on the quality of its adhesion bond strength between the coating and the underlying substrate. Therefore, it is essential to evaluate the adhesion properties of the coating. There are many available test methods for the evaluation of coatings adhesion bond strength. Considering these restrictions of the coated cladding, the scratch test is useful for evaluation of adhesion properties compared to other methods. The purpose of the present study is to analyze the possibility of adhesion bond strength evaluation of ATF coated cladding by scratch testing on coatings cross sections. Experimental approach for adhesion strength of ATF coated cladding was investigated in the present study. The scratch testing was chosen as a testing method. Uncoated zircaloy-4 tube was employed as a reference and plasma spray and arc ion coating were selected as a ATF coated claddings for comparison. As a result, adhesion strengths of specimens affect the measured normal and tangential forces. For the future, the test will be conducted for CrAl coated cladding by laser coating, which is the most promising ATF cladding. Computational analysis with finite element method will also be conducted to analyze a stress distribution in the cladding tube.

Cisplatin Induces Cytotoxicity through the Mitogen-Activated Protein Kinase Pathways ana Activating Transcription Factor 3

Directory of Open Access Journals (Sweden)

Carly St. Germain

2010-07-01

Full Text Available The mechanisms underlying the proapoptotic effect of the chemotherapeutic agent, cisplatin, are largely undefined. Understanding the mechanisms regulating cisplatin cytotoxicity may uncover strategies to enhance the efficacy of this important therapeutic agent. This study evaluates the role of activating transcription factor 3 (ATF3 as a mediator of cisplatin-induced cytotoxicity. Cytotoxic doses of cisplatin and carboplatin treatments consistently induced ATF3 expression in five tumor-derived cell lines. Characterization of this induction revealed a p53, BRCA1, and integrated stress response-independent mechanism, all previously implicated in stress-mediated ATF3 induction. Analysis of mitogenactivated protein kinase (MAPK pathway involvement in ATF3 induction by cisplatin revealed a MAPK-dependent mechanism. Cisplatin treatment combined with specific inhibitors to each MAPK pathway (c-Jun N-terminal kinase, extracellularsignal-regulated kinase, and p38 resulted in decreasedATF3 induction at the protein level. MAPK pathway inhibition led to decreased ATF3 messenger RNA expression and reduced cytotoxic effects of cisplatin as measured by the 3-(4,5-dimethylthiazol-2-ylF2,5-diphenyltetrazolium bromide cell viability assay. In A549 lung carcinoma cells, targeting ATF3 with specific small hairpin RNA also attenuated the cytotoxic effects of cisplatin. Similarly, ATF3-/murine embryonic fibroblasts (MEFs were shown to be less sensitive to cisplatin-induced cytotoxicity compared with ATF3+/+ MEFs. This study identifies cisplatin as a MAPK pathway-dependent inducer of ATF3, whose expression influences cisplatin’s cytotoxic effects.

Loss of ATF2 function leads to cranial motoneuron degeneration during embryonic mouse development.

Directory of Open Access Journals (Sweden)

Julien Ackermann

2011-04-01

Full Text Available The AP-1 family transcription factor ATF2 is essential for development and tissue maintenance in mammals. In particular, ATF2 is highly expressed and activated in the brain and previous studies using mouse knockouts have confirmed its requirement in the cerebellum as well as in vestibular sense organs. Here we present the analysis of the requirement for ATF2 in CNS development in mouse embryos, specifically in the brainstem. We discovered that neuron-specific inactivation of ATF2 leads to significant loss of motoneurons of the hypoglossal, abducens and facial nuclei. While the generation of ATF2 mutant motoneurons appears normal during early development, they undergo caspase-dependent and independent cell death during later embryonic and foetal stages. The loss of these motoneurons correlates with increased levels of stress activated MAP kinases, JNK and p38, as well as aberrant accumulation of phosphorylated neurofilament proteins, NF-H and NF-M, known substrates for these kinases. This, together with other neuropathological phenotypes, including aberrant vacuolisation and lipid accumulation, indicates that deficiency in ATF2 leads to neurodegeneration of subsets of somatic and visceral motoneurons of the brainstem. It also confirms that ATF2 has a critical role in limiting the activities of stress kinases JNK and p38 which are potent inducers of cell death in the CNS.

Electron cyclotron heating calculations for ATF

International Nuclear Information System (INIS)

Goldfinger, R.C.; Batchelor, D.B.

1986-03-01

The RAYS geometrical optics code has been used to calculate electron cyclotron wave propagation and heating in the Advanced Toroidal Facility (ATF) device under construction at Oak Ridge National Laboratory (ORNL). The intent of this work is to predict the outcome of various heating scenarios and to give guidance in designing an optimum heating system. Particular attention is paid to the effects of wave polarization and antenna location. We investigate first and second harmonic cyclotron heating with the parameters predicted for steady-state ATF operation. We also simulate the effect of wall reflections by calculating a uniform, isotropic flux of power radiating from the wall. These results, combined with the first-pass calculations, give a qualitative picture of the heat deposition profiles. From these results we identify the compromises that represent the optimum heating strategies for the ATF model considered here. Our basic conclusions are that second harmonic heating with the extraordinary mode (X-mode) gives the best result, with fundamental ordinary mode (O-mode) heating being slightly less efficient. Assuming the antenna location is restricted to the low magnetic field side, the antenna should be placed at phi = 0 0 (the toroidal angle where the helical coils are at the sides) for fundamental heating and at phi = 15 0 (where the helical coils are at the top and bottom) for second harmonic heating. These recommendations come directly from the ray tracing results as well as from a theoretical identification of the relevant factors affecting the heating

ONC201 kills solid tumor cells by triggering an integrated stress response dependent on ATF4 activation by specific eIF2α kinases

OpenAIRE

Kline, C. Leah B.; Van den Heuvel, A. Pieter J.; Allen, Joshua E.; Prabhu, Varun V.; Dicker, David T.; El-Deiry, Wafik S.

2016-01-01

ONC201 (also called TIC10) is a small molecule that inactivates the cell proliferation- and cell survival-promoting kinases AKT and ERK and induces cell death through the pro-apoptotic protein TRAIL. ONC201 is currently in early phase clinical testing for various malignancies. Here, we found through gene expression and protein analyses that ONC201 triggered an increase in TRAIL abundance and cell death through an integrated stress response (ISR) involving the transcription factor ATF4, the tr...

Hypoxia induces cyclophilin B through the activation of transcription factor 6 in gastric adenocarcinoma cells.

Science.gov (United States)

Jeong, Kwon; Kim, Kiyoon; Kim, Hunsung; Oh, Yoojung; Kim, Seong-Jin; Jo, Yunhee; Choe, Wonchae

2015-06-01

Hypoxia is an important form of physiological stress that induces cell death, due to the resulting endoplasmic reticulum (ER) stress, particularly in solid tumors. Although previous studies have indicated that cyclophilin B (CypB) plays a role in ER stress, there is currently no direct information supporting the mechanism of CypB involvement under hypoxic conditions. However, it has previously been demonstrated that ER stress positively regulates the expression of CypB. In the present study, it was demonstrated that CypB is transcriptionally regulated by hypoxia-mediated activation of transcription factor 6 (ATF6), an ER stress transcription factor. Subsequently, the effects of ATF6 on CypB promoter activity were investigated and an ATF6-responsive region in the promoter was identified. Hypoxia and ATF6 expression each increased CypB promoter activity. Collectively, these results demonstrate that ATF6 positively regulates the expression of CypB by binding to an ATF6-responsive region in the promoter, which may play an important role in the attenuation of apoptosis in the adaption to hypoxia. These results suggest that CypB may be a key molecule in the adaptation of cells to hypoxic conditions.

ATF5 polymorphisms influence ATF function and response to treatment in children with childhood acute lymphoblastic leukemia

OpenAIRE

Rousseau, Julie; Gagné, Vincent; Labuda, Malgorzata; Beaubois, Cyrielle; Sinnett, Daniel; Laverdière, Caroline; Moghrabi, Albert; Sallan, Stephen E.; Silverman, Lewis B.; Neuberg, Donna; Kutok, Jeffery L.; Krajinovic, Maja

2011-01-01

Asparaginase is a standard and critical component in the therapy of childhood acute lymphoblastic leukemia. Asparagine synthetase (ASNS) and the basic region leucine zipper activating transcription factor 5 (ATF5) and arginosuccinate synthase 1 (ASS1) have been shown to mediate the antileukemic effect of asparaginase and to display variable expression between leukemia cells that are resistant and sensitive to treatment. Fourteen polymorphisms in the regulatory and coding regions of these gene...

Comprehensive Behavioral Analysis of Activating Transcription Factor 5-Deficient Mice

Directory of Open Access Journals (Sweden)

Mariko Umemura

2017-07-01

Full Text Available Activating transcription factor 5 (ATF5 is a member of the CREB/ATF family of basic leucine zipper transcription factors. We previously reported that ATF5-deficient (ATF5-/- mice demonstrated abnormal olfactory bulb development due to impaired interneuron supply. Furthermore, ATF5-/- mice were less aggressive than ATF5+/+ mice. Although ATF5 is widely expressed in the brain, and involved in the regulation of proliferation and development of neurons, the physiological role of ATF5 in the higher brain remains unknown. Our objective was to investigate the physiological role of ATF5 in the higher brain. We performed a comprehensive behavioral analysis using ATF5-/- mice and wild type littermates. ATF5-/- mice exhibited abnormal locomotor activity in the open field test. They also exhibited abnormal anxiety-like behavior in the light/dark transition test and open field test. Furthermore, ATF5-/- mice displayed reduced social interaction in the Crawley’s social interaction test and increased pain sensitivity in the hot plate test compared with wild type. Finally, behavioral flexibility was reduced in the T-maze test in ATF5-/- mice compared with wild type. In addition, we demonstrated that ATF5-/- mice display disturbances of monoamine neurotransmitter levels in several brain regions. These results indicate that ATF5 deficiency elicits abnormal behaviors and the disturbance of monoamine neurotransmitter levels in the brain. The behavioral abnormalities of ATF5-/- mice may be due to the disturbance of monoamine levels. Taken together, these findings suggest that ATF5-/- mice may be a unique animal model of some psychiatric disorders.

Proceedings of the SLAC/KEK ATF lattice workshop

International Nuclear Information System (INIS)

Urakawa, Junji

1993-04-01

The SLAC/KEK ATF Lattice Workshop was held on December 8-11, 1992 at KEK, National Laboratory for High Energy Physics. The purpose of this workshop is to critically review the ATF lattice design for any possible improvements, and also to bring SLAC colleagues up to date on recent progress at KEK. At KEK studies on intense multi-bunch beam acceleration and emittance reduction have been actively pursued, evolving into the ATF project since 1990. In 1991 we have launched a large scale reconstruction of the experimental hall. This is to build the shielded housing for the 1.54 GeV injector linac and the test damping ring. Our plan is to begin construction of the linac in March 1993. Some results from the discussions during the Workshop have been already incorporated in the revised ATF lattice design. (J.P.N.)

Achievement of ultra-low emittance beam in the ATF damping ring

CERN Document Server

Honda, Y; Araki, S; Bane, Karl Leopold Freitag; Brachmann, A; Frisch, J; Fukuda, M; Hasegawa, K; Hayano, H; Hendrickson, L; Higashi, Y; Higo, T; Hirano, K; Hirose, T; Iida, K; Imai, T; Inoue, Y; Karataev, P; Kubo, K; Kurihara, Y; Kuriki, M; Kuroda, R; Kuroda, S; Luo, X; Matsuda, M; McCormick, D; Muto, T; Nakajima, K; Nelson, J; Nomura, M; Ohashi, A; Okugi, T; Omori, T; Ross, M; Sakai, H; Sakai, I; Sasao, N; Smith, S; Suzuki, T; Takano, M; Takashi, N; Taniguchi, T; Terunuma, N; Toge, N; Turner, J; Urakawa, J; Vogel, V; Wolski, A; Woodley, M; Yamazaki, I; Yamazaki, Y; Yocky, J; Young, A; Zimmermann, Frank

2003-01-01

We report on the smallest vertical emittance achieved in single-bunch-mode operation of the ATF. The emittances were measured with a laser-wire beam-profile monitor installed in the damping ring. The bunch length and the momentum spread of the beam were also recorded under the same conditions. The smallest vertical rms emittance measured is 4 pm in the limit of zero current. It increases by a factor of 1.5 for a bunch intensity of 10^10 electrons. There are no discrepancies between the measured data and the calculations of intra-beam scattering.

v-src induction of the TIS10/PGS2 prostaglandin synthase gene is mediated by an ATF/CRE transcription response element.

Science.gov (United States)

Xie, W; Fletcher, B S; Andersen, R D; Herschman, H R

1994-10-01

We recently reported the cloning of a mitogen-inducible prostaglandin synthase gene, TIS10/PGS2. In addition to growth factors and tumor promoters, the v-src oncogene induces TIS10/PGS2 expression in 3T3 cells. Deletion analysis, using luciferase reporters, identifies a region between -80 and -40 nucleotides 5' of the TIS10/PGS2 transcription start site that mediates pp60v-src induction in 3T3 cells. This region contains the sequence CGTCACGTG, which includes overlapping ATF/CRE (CGTCA) and E-box (CACGTG) sequences. Gel shift-oligonucleotide competition experiments with nuclear extracts from cells stably transfected with a temperature-sensitive v-src gene demonstrate that the CGTCACGTG sequence can bind proteins at both the ATF/CRE and E-box sequences. Dominant-negative CREB and Myc proteins that bind DNA, but do not transactivate, block v-src induction of a luciferase reporter driven by the first 80 nucleotides of the TIS10/PGS2 promoter. Mutational analysis distinguishes which TIS10/PGS2 cis-acting element mediates pp60v-src induction. E-box mutation has no effect on the fold induction in response to pp60v-src. In contrast, ATF/CRE mutation attenuates the pp60v-src response. Antibody supershift and methylation interference experiments demonstrate that CREB and at least one other ATF transcription factor in these extracts bind to the TIS10/PGS2 ATF/CRE element. Expression of a dominant-negative ras gene also blocks TIS10/PGS2 induction by v-src. Our data suggest that Ras mediates pp60v-src activation of an ATF transcription factor, leading to induced TIS10/PGS2 expression via the ATF/CRE element of the TIS10/PGS2 promoter. This is the first description of v-src activation of gene expression via an ATF/CRE element.

R and D status of the ATF damping ring

International Nuclear Information System (INIS)

Urakawa, Junji

1994-01-01

The KEK accelerator test facility (ATF) is under construction. This paper gives the status of the design studies, the various R and D works and the construction for the damping ring of the ATF. (author)

Regulation of the human ADAMTS-4 promoter by transcription factors and cytokines

International Nuclear Information System (INIS)

Thirunavukkarasu, Kannan; Pei, Yong; Moore, Terry L.; Wang, He; Yu, Xiao-peng; Geiser, Andrew G.; Chandrasekhar, Srinivasan

2006-01-01

ADAMTS-4 (aggrecanase-1) is a metalloprotease that plays a role in aggrecan degradation in the cartilage extracellular matrix. In order to understand the regulation of ADAMTS-4 gene expression we have cloned and characterized a functional 4.5 kb human ADAMTS-4 promoter. Sequence analysis of the promoter revealed the presence of putative binding sites for nuclear factor of activated T cells (NFAT) and Runx family of transcription factors that are known to regulate chondrocyte maturation and differentiation. Using promoter-reporter assays and mRNA analysis we have analyzed the role of chondrocyte-expressed transcription factors NFATp and Runx2 and have shown that ADAMTS-4 is a potential downstream target of these two factors. Our results suggest that inhibition of the expression/function of NFATp and/or Runx2 may enable us to modulate aggrecan degradation in normal physiology and/or in degenerative joint diseases. The ADAMTS-4 promoter would serve as a valuable mechanistic tool to better understand the regulation of ADAMTS-4 expression by signaling pathways that modulate cartilage matrix breakdown

Design and high order optimization of the ATF2 lattices

CERN Document Server

Marin, E; Woodley, M; Kubo, K; Okugi, T; Tauchi, T; Urakawa, J; Tomas, R

2013-01-01

The next generation of future linear colliders (LC) demands nano-meter beam sizes at the interaction point (IP) in order to reach the required luminosity. The final focus system (FFS) of a LC is meant to deliver such small beam sizes. The Accelerator Test Facility (ATF) aims to test the feasibility of the new local chromaticity correction scheme which the future LCs are based on. To this end the ATF2 nominal and ultra-low beta* lattices are design to vertically focus the beam at the IP to 37nm and 23nm, respectively if error-free lattices are considered. However simulations show that the measured field errors of the ATF2 magnets preclude to reach the mentioned spot sizes. This paper describes the optimization of high order aberrations of the ATF2 lattices in order to minimize the detrimental effect of the measured multipole components for both ATF2 lattices. Specifically three solutions are studied, the replacement of the last focusing quadrupole (QF1FF), insertion of octupole magnets and optics modification....

ATF-1 torsatron studies

International Nuclear Information System (INIS)

Lyon, J.F.; Carreras, B.A.; Charlton, L.A.

1983-01-01

The main advances in the ORNL Stellarator Program since the 1982 IAEA Conference have been: (1) engineering design of the ATF-1 torsatron; (2) extension of 3-D MHD equilibrium and stability studies and calculations of helical axis configurations; (3) study of stable equilibria with greater than or equal to 8% and direct access to the second stability regime; (4) 3-D Monte Carlo and analytic transport calculations which show a large reduction in transport at low collisionality for the absolute value of e phi'/T' greater than or equal to 1; (5) calculation of ambipolar electric fields; and (b) calculation of well confined ion drift surfaces in the ergodic field region outside the last closed flux surface

Lifetime measurement of ATF damping ring

International Nuclear Information System (INIS)

Okugi, T.; Hayano, H.; Kubo, K.; Naito, T.; Terunuma, N.; Urakawa, J.; Zimmermann, F.

1998-06-01

The purpose of the ATF damping ring is the development of technologies for producing a low emittance beam required in future linear colliders such as JLC. The lifetime of the damping ring is very short (typically a few minutes). It is limited by elastic beam-gas scattering along with a small dynamic aperture, and by single intra-beam scattering (Touschek effect). The Touschek lifetime strongly depends upon the charge density of the beam, especially, the size of the vertical emittance. In this paper, the authors report the results of beam lifetime measurements in the ATF damping ring and the estimation of the vertical emittance from these measurements

Wolfram syndrome 1 gene negatively regulates ER stress signaling in rodent and human cells.

Science.gov (United States)

Fonseca, Sonya G; Ishigaki, Shinsuke; Oslowski, Christine M; Lu, Simin; Lipson, Kathryn L; Ghosh, Rajarshi; Hayashi, Emiko; Ishihara, Hisamitsu; Oka, Yoshitomo; Permutt, M Alan; Urano, Fumihiko

2010-03-01

Wolfram syndrome is an autosomal-recessive disorder characterized by insulin-dependent diabetes mellitus, caused by nonautoimmune loss of beta cells, and neurological dysfunctions. We have previously shown that mutations in the Wolfram syndrome 1 (WFS1) gene cause Wolfram syndrome and that WFS1 has a protective function against ER stress. However, it remained to be determined how WFS1 mitigates ER stress. Here we have shown in rodent and human cell lines that WFS1 negatively regulates a key transcription factor involved in ER stress signaling, activating transcription factor 6alpha (ATF6alpha), through the ubiquitin-proteasome pathway. WFS1 suppressed expression of ATF6alpha target genes and repressed ATF6alpha-mediated activation of the ER stress response element (ERSE) promoter. Moreover, WFS1 stabilized the E3 ubiquitin ligase HRD1, brought ATF6alpha to the proteasome, and enhanced its ubiquitination and proteasome-mediated degradation, leading to suppression of ER stress signaling. Consistent with these data, beta cells from WFS1-deficient mice and lymphocytes from patients with Wolfram syndrome exhibited dysregulated ER stress signaling through upregulation of ATF6alpha and downregulation of HRD1. These results reveal a role for WFS1 in the negative regulation of ER stress signaling and in the pathogenesis of diseases involving chronic, unresolvable ER stress, such as pancreatic beta cell death in diabetes.

CAVITY BEAM POSITION MONITOR SYSTEM FOR ATF2

CERN Document Server

Boogert, S T; Boorman, G; Molloy, S; Ross, M; Aryshev, A; Honda, Y; Terunuma, N; Urakawa, J; Kim, E S; Kim, Y I; Heo, A E; Lyapin, A; Swinson, C J; Frisch, J; McCormick, D M; Nelson, J; Smith, T; White, G R

2010-01-01

The Accelerator Test Facility 2 (ATF2) in KEK, Japan, is a prototype scaled demonstrator system for the final focus required for a future high energy lepton linear collider. The ATF2 beam-line is instrumented with a total of 38 C and S band resonant cavity beam position monitors (CBPM) with associated mixer electronics and digitizers. The current status of the BPM system is described, with a focus on operational techniques and performance.

Vibration measurement of accelerator tube table in ATF

International Nuclear Information System (INIS)

Nakayama, Y.; Sugahara, R.; Yamaoka, H.; Masuzawa, M.; Yamashita, S.

2004-01-01

Acceleration tube fixed to the table should not be a structure to amplify the vibration. Stability of ground is preferable for accelerator beam operation, and the beam control by extremely high resolution is especially demanded in GLC. Then, we have measured ground motion and table vibration in ATF at KEK. In this paper, some of analyzed results are shown, and we show the characteristics of vibration about the accelerator tube table in ATF. (author)

v-src Induction of the TIS10/PGS2 prostaglandin synthase gene is mediated by an ATF/CRE transcription response element

Energy Technology Data Exchange (ETDEWEB)

Xie, W.; Fletcher, B.S.; Andersen, R.D.; Herschman, H.R. [Univ. of California, Los Angeles, CA (United States)

1994-10-01

The authors recently reported the cloning of a mitogen-inducible prostaglandin synthase gene, TIS10/PGS2. In addition to growth factor and tumor promoters, the v-src oncogene induces TIS10/PGS2 expression in 3T3 cells. Deletion analysis, using luciferase reporters, identifies a region between -80 and -40 nucleotides 5{prime} of the TIS10/PGS2 transcription start site that mediates pp60{sup v-src} induction in 3T3 cells. This region contains the sequence CGTCACGTG, which includes overlapping ATF/CRE (CGTCA) and E-box (CACGTG) sequences. Gel shift-oligonucleotide competition experiments with nuclear extracts from cells stably transfected with a temperature-sensitive v-src gene demonstrate that the CGTCACGTG sequence can bind proteins at both the AFT/CRE and E-box sequences. Dominant-negative CREB and Myc proteins that bind DNA, but do not transactivate, block v-src induction of a luciferase reporter driven by the first 80 nucleotides of the TIS10/PGS2 promoter. Mutational analysis distinguishes which TIS10/PGS2 cis-acting element mediates pp60{sup v-src} induction. E-box mutation has no effect on the fold induction in response to pp60{sup v-src}. In contrast, ATF/CRE mutation attenuates the pp{sup v-src} response. Antibody supershift and methylation interference experiments demonstrate that CREB and at least one other ATF transcription factor in these extracts bind to the TIS10/PGS2 ATF/CRE element. Expression of a dominant-negative ras gene also blocks TIS10/PGS2 induction by v-src. The data suggest that Ras mediates pp60{sup v-src} activation of an ATF transcription factor, leading to induced TIS10/PGS2 expression via the ATF/CRE element of the TIS10/PGS2 promoter. This is the first description of v-src activation of gene expression via an ATF/CRE element. 64 refs., 8 figs.

APETALA 2-domain-containing transcription factors: focusing on abscisic acid and gibberellins antagonism.

Science.gov (United States)

Shu, Kai; Zhou, Wenguan; Yang, Wenyu

2018-02-01

The phytohormones abscisic acid (ABA) and gibberellin (GA) antagonistically mediate diverse plant developmental processes including seed dormancy and germination, root development, and flowering time control, and thus the optimal balance between ABA and GA is essential for plant growth and development. Although more than a half and one century have passed since the initial discoveries of ABA and GA, respectively, the precise mechanisms underlying ABA-GA antagonism still need further investigation. Emerging evidence indicates that two APETALA 2 (AP2)-domain-containing transcription factors (ATFs), ABI4 in Arabidopsis and OsAP2-39 in rice, play key roles in ABA and GA antagonism. These two transcription factors precisely regulate the transcription pattern of ABA and GA biosynthesis or inactivation genes, mediating ABA and GA levels. In this Viewpoint article, we try to shed light on the effects of ATFs on ABA-GA antagonism, and summarize the overlapping but distinct biological functions of these ATFs in the antagonism between ABA and GA. Finally, we strongly propose that further research is needed into the detailed roles of additional numerous ATFs in ABA and GA crosstalk, which will improve our understanding of the antagonism between these two phytohormones. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Activation of the unfolded protein response during anoxia exposure in the turtle Trachemys scripta elegans.

Science.gov (United States)

Krivoruchko, Anastasia; Storey, Kenneth B

2013-02-01

Red-eared slider turtles, Trachemys scripta elegans, can survive for several weeks without oxygen when submerged in cold water. We hypothesized that anaerobiosis is aided by adaptive up-regulation of the unfolded protein response (UPR), a stress-responsive pathway that is activated by accumulation of unfolded proteins in the endoplasmic reticulum (ER) and functions to restore ER homeostasis. RT-PCR, western immunoblotting and DNA-binding assays were used to quantify the responses and/or activation status of UPR-responsive genes and proteins in turtle tissues after animal exposure to 5 or 20 h of anoxic submergence at 4 °C. The phosphorylation state of protein kinase-like ER kinase (PERK) (a UPR-regulated kinase) and eukaryotic initiation factor 2 (eIF2α) increased by 1.43-2.50 fold in response to anoxia in turtle heart, kidney, and liver. Activation of the PERK-regulated transcription factor, activating transcription factor 4 (ATF4), during anoxia was documented by elevated atf4 transcripts and total ATF4 protein (1.60-2.43 fold), increased nuclear ATF4 content, and increased DNA-binding activity (1.44-2.32 fold). ATF3 and GADD34 (downstream targets of ATF4) also increased by 1.38-3.32 fold in heart and liver under anoxia, and atf3 transcripts were also elevated in heart. Two characteristic chaperones of the UPR, GRP78, and GRP94, also responded positively to anoxia with strong increases in both the transcript and protein levels. The data demonstrate that the UPR is activated in turtle heart, kidney, and liver in response to anoxia, suggesting that this pathway mediates an integrated stress response to protect tissues during oxygen deprivation.

Activating transcription factor 3 promotes loss of the acinar cell phenotype in response to cerulein-induced pancreatitis in mice.

Science.gov (United States)

Fazio, Elena N; Young, Claire C; Toma, Jelena; Levy, Michael; Berger, Kurt R; Johnson, Charis L; Mehmood, Rashid; Swan, Patrick; Chu, Alphonse; Cregan, Sean P; Dilworth, F Jeffrey; Howlett, Christopher J; Pin, Christopher L

2017-09-01

Pancreatitis is a debilitating disease of the exocrine pancreas that, under chronic conditions, is a major susceptibility factor for pancreatic ductal adenocarcinoma (PDAC). Although down-regulation of genes that promote the mature acinar cell fate is required to reduce injury associated with pancreatitis, the factors that promote this repression are unknown. Activating transcription factor 3 (ATF3) is a key mediator of the unfolded protein response, a pathway rapidly activated during pancreatic insult. Using chromatin immunoprecipitation followed by next-generation sequencing, we show that ATF3 is bound to the transcriptional regulatory regions of >30% of differentially expressed genes during the initiation of pancreatitis. Of importance, ATF3-dependent regulation of these genes was observed only upon induction of pancreatitis, with pathways involved in inflammation, acinar cell differentiation, and cell junctions being specifically targeted. Characterizing expression of transcription factors that affect acinar cell differentiation suggested that acinar cells lacking ATF3 maintain a mature cell phenotype during pancreatitis, a finding supported by maintenance of junctional proteins and polarity markers. As a result, Atf3 -/- pancreatic tissue displayed increased tissue damage and inflammatory cell infiltration at early time points during injury but, at later time points, showed reduced acinar-to-duct cell metaplasia. Thus our results reveal a critical role for ATF3 as a key regulator of the acinar cell transcriptional response during injury and may provide a link between chronic pancreatitis and PDAC. © 2017 Fazio et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

Inverse Cerenkov laser acceleration experiment at ATF

International Nuclear Information System (INIS)

Wang, X.J.; Pogorelsky, I.; Fernow, R.; Kusche, K.P.; Liu, Y.; Kimura, W.D.; Kim, G.H.; Romea, R.D.; Steinhauer, L.C.

1994-01-01

Inverse Cerenkov laser acceleration was demonstrated using an axicon optical system at the Brookhaven Accelerator Test Facility (ATF). The ATF S-band linac and a high power 10.6 μm CO 2 laser were used for the experiment. Experimental arrangement and the laser and the electron beams synchronization are discussed. The electrons were accelerated more than 0.7 MeV for a 34 MW CO 2 laser power. More than 3.7 MeV acceleration was measured with 0.7 GW CO 2 laser power, which is more than 20 times of the previous ICA experiment. The experimental results are compared with computer program TRANSPORT simulations

Fluctuations and confinement in ATF

International Nuclear Information System (INIS)

Isler, R.C.; Harris, J.H.; Murakami, M.

1993-01-01

In the period immediately prior to the suspension of ATF operation in November, 1991, a great deal of emphasis was palced on investigations of the fundamental mechanisms controlling confinement in this device. At that time, measurements of the density fluctuations throughout the plasma volume indicated the existence of theoretically predicted dissipative trapped electron and resistive interchange instabilities. These identifications were supported by results of dynamic configuration scans of the magnetic fields during which the extent of the magnetic well, shear, and fraction of confined trapped particles were changed continuously. Interpretation of the data from these experiments has been an ongoing exercise. Most recently, analysis of discharges employing strong gas puffing to change density gradients and fluctuation levels have strengthened the view that dissipative trapped electron modes may be present but do not play a significant direct role in energy transport. The present paper summarizes the current understanding concerning the identification of instabilities and their relationship to confinement in ATF

Induction of Liver Steatosis and Lipid Droplet Formation in ATF6α-Knockout Mice Burdened with Pharmacological Endoplasmic Reticulum Stress

OpenAIRE

Harada, Akihiro; Okada, Tetsuya; Sato, Takashi; Mori, Kazutoshi; Yamamoto, Keisuke; Takahara, Kazuna; Oyadomari, Seiichi

2010-01-01

Accumulation of unfolded proteins in the endoplasmic reticulum (ER) activates homeostatic responses collectively termed the unfolded protein response. Among the three principal signaling pathways operating in mammals, activating transcription factor (ATF)6? plays a pivotal role in transcriptional induction of ER-localized molecular chaperones and folding enzymes as well as components of ER-associated degradation, and thereby mouse embryonic fibroblasts deficient in ATF6? are sensitive to ER s...

Larval hemolymph of rhinoceros beetle, Allomyrina dichotoma, enhances insulin secretion through ATF3 gene expression in INS-1 pancreatic β-cells.

Science.gov (United States)

Kim, Seung-Whan; Suh, Hyun-Woo; Yoo, Bo-Kyung; Kwon, Kisang; Yu, Kweon; Choi, Ji-Young; Kwon, O-Yu

2018-05-22

In this study, we show that INS-1 pancreatic β-cells treated for 2 h with hemolymph of larvae of rhinoceros beetle, Allomyrina dichotoma, secreted about twice as much insulin compared to control cells without such treatment. Activating transcription factor 3 (ATF3) was the highest upregulated gene in DNA chip analysis. The A. dichotoma hemolymph dose-dependently induced increased expression levels of genes encoding ATF3 and insulin. Conversely, treatment with ATF3 siRNA inhibited expression levels of both genes and curbed insulin secretion. These results suggest that the A. dichotoma hemolymph has potential for treating and preventing diabetes or diabetes-related complications.

Avian metapneumovirus subgroup C induces autophagy through the ATF6 UPR pathway.

Science.gov (United States)

Hou, Lei; Wei, Li; Zhu, Shanshan; Wang, Jing; Quan, Rong; Li, Zixuan; Liu, Jue

2017-10-03

An increasing number of studies have demonstrated that macroautophagy/autophagy plays an important role in the infectious processes of diverse pathogens. However, it remains unknown whether autophagy is induced in avian metapneumovirus (aMPV)-infected host cells, and, if so, how this occurs. Here, we report that aMPV subgroup C (aMPV/C) induces autophagy in cultured cells. We demonstrated this relationship by detecting classical autophagic features, including the formation of autophagsomes, the presence of GFP-LC3 puncta and the conversation of LC3-I into LC3-II. Also, we used pharmacological regulators and siRNAs targeting ATG7 or LC3 to examine the role of autophagy in aMPV/C replication. The results showed that autophagy is required for efficient replication of aMPV/C. Moreover, infection with aMPV/C promotes autophagosome maturation and induces a complete autophagic process. Finally, the ATF6 pathway, of which one component is the unfolded protein response (UPR), becomes activated in aMPV/C-infected cells. Knockdown of ATF6 inhibited aMPV/C-induced autophagy and viral replication. Collectively, these results not only show that autophagy promotes aMPV/C replication in the cultured cells, but also reveal that the molecular mechanisms underlying aMPV/C-induced autophagy depends on regulation of the ER stress-related UPR pathway.

The ATF [Advanced Toroidal Facility] Data Management System: [Final report

International Nuclear Information System (INIS)

Kannan, K.L.; Baylor, L.R.

1987-01-01

The Advanced Toroidal Facility (ATF) Data Management System (DMG) is a VAX-based software system that provides unified data access for ATF data acquisition and analysis. The system was designed with user accessibility, software maintainability, and extensibility as primary goals. This paper describes the layered architecture of the system design, the system implementation, use, and the data file structure. 3 refs., 1 fig

Stimulation of p38 (HOG1) kinase pathway by ionizing radiation results in downstream modulation of ATF/CREB transcription factor activity in NIH-3T3 cells

International Nuclear Information System (INIS)

Stevenson, Mary Ann; Yao Jin

1997-01-01

Purpose/Objective:p38 kinase, a member of the MAP kinase family, is activated in response to stresses such as high osmolarity and UV irradiation as well exposure to cytokines such as IL1β and TNFα. The kinase is part of a signal transduction pathway that leads from receptor activation through a three kinase cascade resulting in the activation of p38. p38 activation then leads to the phosphorylation of target proteins that include transcription factors such as nuclear factor of interleukin 6 and members of the activating transcription factor (ATF) family, and in addition, the stress protein, HSP27, via activation of MAPKAP2 kinase. In the present report, we have investigated the potential role of p38 in the response of NIH-3T3 cells to ionizing radiation. Materials and Methods:NIH-3T3 cells were grown to confluence in DMEM+10%CS and then serum deprived for 24 hours in DMEM+0.1%CS. Radiation exposures were delivered using a Philips RT250 (250Kvp X-ray tube). Activated forms of p38 kinase and ATF/CREB transcription factors were identified using immunoblotting techniques employing activation specific antibodies raised against the phosphorylated forms of the kinases/transcription factors. Kinase activity was directly measured using immunokinase assays. DNA binding of transcription factors to their respective consensus sequences was assayed by EMSA. Results:We found that p38 becomes rapidly phosphorylated and activated by exposure to ionizing radiation. Significantly, p38 is activated to a similar degree and with a similar time course by serum derpviation and entry of cells into a non-proliferating G 0 state, suggesting a causal role for p38 in quiescence. Phosphorylation of p38 directly correlated with phosphorylation and activation of ATF/CREB family members as well as DNA binding by these activated factors. Conclusion:Activation of p38 kinase and downstream transcription factors may play an important role in the response of cells to ionizing radiation. We are

Mechanical Property and Oxidation Behavior of ATF cladding developed in KAERI

Energy Technology Data Exchange (ETDEWEB)

Kim, Hyun-Gil; Kim, Il-Hyun; Jung, Yang-Il; Park, Dong-Jun; Park, Jung-Hwan; Park, Jeong-Yong; Koo, Yang-Hyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-10-15

To realize the coating cladding, coating material (Cr-based alloy) as well as coating technology (3D laser coating and arc ion plating combined with vacuum annealing) can be developed to meet the fuel cladding criteria. The coated Zr cladding can be produced after the optimization of coating technologies. The coated cladding sample showed the good oxidation/corrosion and adhesion properties without the spalling and/or severe interaction with the Zr alloy cladding from the various tests. Thus, it is known that the mechanical property and oxidation behavior of coated cladding concept developed in KAERI is reasonable for applying the ATF cladding in LWRs. At the present time various ATF concepts have been proposed and developing in many countries. The ATF concepts with potentially improved accident performance can be summarized to the coating cladding, Mo-Zr cladding, FeCrAl cladding, and SiCf/SiC cladding. Regarding the cladding performance, ATF cladding concepts will be evaluated with respect to the accident scenarios and normal operations of LWRs as well as to the fuel cladding fabrication.

Myocardin-related transcription factor regulates Nox4 protein expression

DEFF Research Database (Denmark)

Rozycki, Matthew; Bialik, Janne Folke; Speight, Pam

2016-01-01

translocation of MRTF. Because the Nox4 promoter harbors a serum response factor/MRTF cis-element (CC(A/T)6GG box), we asked if MRTF (and thus cytoskeleton organization) could regulate Nox4 expression. We show that Nox4 protein is robustly induced in kidney tubular cells exclusively by combined application...... TGFβ/contact disruption-provoked Nox4 protein and mRNA expression, Nox4 promoter activation, and reactive oxygen species production. Mutation of the CC(A/T)6GG box eliminates the synergistic activation of the Nox4 promoter. Jasplakinolide-induced actin polymerization synergizes with TGFβ to facilitate...... MRTF-dependent Nox4 mRNA expression/promoter activation. Moreover, MRTF inhibition prevents Nox4 expression during TGFβ-induced fibroblast-myofibroblast transition as well. Although necessary, MRTF is insufficient; Nox4 expression also requires TGFβ-activated Smad3 and TAZ/YAP, two contact...

ATF2 spot size tuning using the rotation matrix

CERN Document Server

Scarfe, A; Jones, J K; Angal-Kalinin, D

2010-01-01

The Accelerator Test Facility (ATF2) at KEK aims to experimentally verify the local chromaticity correction scheme to achieve a vertical beam size of 37nm. The facility is a scaled down version of the final focus design proposed for the future linear colliders. In order to achieve this goal, high precision tuning methods are being developed. One of the methods proposed for ATF2 is a novel method known as the ‘rotation matrix’ method. Details of the development and testing of this method, including orthogonality optimisation and simulation methods, are presented.

The FONT5 Bunch-by-Bunch Position and Angle Feedback System at ATF2

Science.gov (United States)

Apsimon, R. J.; Bett, D. R.; Burrows, P. N.; Christian, G. B.; Constance, B.; Davis, M. R.; Gerbershagen, A.; Perry, C.; Resta-Lopez, J.

The FONT5 upstream beam-based feedback system at ATF2 is designed to correct the position and angle jitter at the entrance to the ATF2 final-focus system, and also to demonstrate a prototype intra-train feedback system for the International Linear Collider interaction point. We discuss the hardware, from stripline BPMs to kickers, and RF and digital signal processing, as well as presenting results from the latest beam tests at ATF2.

Polysaccharide from Angelica sinensis protects H9c2 cells against oxidative injury and endoplasmic reticulum stress by activating the ATF6 pathway.

Science.gov (United States)

Niu, Xiaowei; Zhang, Jingjing; Ling, Chun; Bai, Ming; Peng, Yu; Sun, Shaobo; Li, Yingdong; Zhang, Zheng

2018-01-01

Objectives Angelica sinensis exerts various pharmacological effects, such as antioxidant and anti-apoptotic activity. This study aimed to investigate the active ingredients in A. sinensis with antioxidant properties and whether A. sinensis polysaccharide (ASP) protects H9c2 cells against oxidative and endoplasmic reticulum (ER) stress. Methods The ingredients of A. sinensis and their targets and related pathways were determined using web-based databases. Markers of oxidative stress, cell viability, apoptosis, and ER stress-related signalling pathways were measured in H9c2 cells treated with hydrogen peroxide (H 2 O 2 ) and ASP. Results The ingredient-pathway-disease network showed that A. sinensis exerted protective effects against oxidative injury through its various active ingredients on regulation of multiple pathways. Subsequent experiments showed that ASP pretreatment significantly decreased H 2 O 2 -induced cytotoxicity and apoptosis in H9c2 cells. ASP pretreatment inhibited H 2 O 2 -induced reactive oxygen species generation, lactic dehydrogenase release, and malondialdehyde production. ASP exerted beneficial effects by inducing activating transcription factor 6 (ATF6) and increasing ATF6 target protein levels, which in turn attenuated ER stress and increased antioxidant activity. Conclusions Our findings indicate that ASP, a major water-soluble component of A. sinensis, exerts protective effects against H 2 O 2 -induced injury in H9c2 cells by activating the ATF6 pathway, thus ameliorating ER and oxidative stress.

Intestinal DMBT1 expression is modulated by Crohn's disease-associated IL23R variants and by a DMBT1 variant which influences binding of the transcription factors CREB1 and ATF-2.

Directory of Open Access Journals (Sweden)

Julia Diegelmann

Full Text Available OBJECTIVES: DMBT is an antibacterial pattern recognition and scavenger receptor. In this study, we analyzed the role of DMBT1 single nucleotide polymorphisms (SNPs regarding inflammatory bowel disease (IBD susceptibility and examined their functional impact on transcription factor binding and downstream gene expression. METHODS: Seven SNPs in the DMBT1 gene region were analyzed in 2073 individuals including 818 Crohn's disease (CD patients and 972 healthy controls in two independent case-control panels. Comprehensive epistasis analyses for the known CD susceptibility genes NOD2, IL23R and IL27 were performed. The influence of IL23R variants on DMBT1 expression was analyzed. Functional analysis included siRNA transfection, quantitative PCR, western blot, electrophoretic mobility shift and luciferase assays. RESULTS: IL-22 induces DMBT1 protein expression in intestinal epithelial cells dependent on STAT3, ATF-2 and CREB1. IL-22 expression-modulating, CD risk-associated IL23R variants influence DMBT1 expression in CD patients and DMBT1 levels are increased in the inflamed intestinal mucosa of CD patients. Several DMBT1 SNPs were associated with CD susceptibility. SNP rs2981804 was most strongly associated with CD in the combined panel (p = 3.0 × 10(-7, OR 1.42; 95% CI 1.24-1.63. All haplotype groups tested showed highly significant associations with CD (including omnibus P-values as low as 6.1 × 10(-18. The most strongly CD risk-associated, non-coding DMBT1 SNP rs2981804 modifies the DNA binding sites for the transcription factors CREB1 and ATF-2 and the respective genomic region comprising rs2981804 is able to act as a transcriptional regulator in vitro. Intestinal DMBT1 expression is decreased in CD patients carrying the rs2981804 CD risk allele. CONCLUSION: We identified novel associations of DMBT1 variants with CD susceptibility and discovered a novel functional role of rs2981804 in regulating DMBT1 expression. Our data suggest an important

Intestinal DMBT1 expression is modulated by Crohn's disease-associated IL23R variants and by a DMBT1 variant which influences binding of the transcription factors CREB1 and ATF-2.

Science.gov (United States)

Diegelmann, Julia; Czamara, Darina; Le Bras, Emmanuelle; Zimmermann, Eva; Olszak, Torsten; Bedynek, Andrea; Göke, Burkhard; Franke, Andre; Glas, Jürgen; Brand, Stephan

2013-01-01

DMBT is an antibacterial pattern recognition and scavenger receptor. In this study, we analyzed the role of DMBT1 single nucleotide polymorphisms (SNPs) regarding inflammatory bowel disease (IBD) susceptibility and examined their functional impact on transcription factor binding and downstream gene expression. Seven SNPs in the DMBT1 gene region were analyzed in 2073 individuals including 818 Crohn's disease (CD) patients and 972 healthy controls in two independent case-control panels. Comprehensive epistasis analyses for the known CD susceptibility genes NOD2, IL23R and IL27 were performed. The influence of IL23R variants on DMBT1 expression was analyzed. Functional analysis included siRNA transfection, quantitative PCR, western blot, electrophoretic mobility shift and luciferase assays. IL-22 induces DMBT1 protein expression in intestinal epithelial cells dependent on STAT3, ATF-2 and CREB1. IL-22 expression-modulating, CD risk-associated IL23R variants influence DMBT1 expression in CD patients and DMBT1 levels are increased in the inflamed intestinal mucosa of CD patients. Several DMBT1 SNPs were associated with CD susceptibility. SNP rs2981804 was most strongly associated with CD in the combined panel (p = 3.0 × 10(-7), OR 1.42; 95% CI 1.24-1.63). All haplotype groups tested showed highly significant associations with CD (including omnibus P-values as low as 6.1 × 10(-18)). The most strongly CD risk-associated, non-coding DMBT1 SNP rs2981804 modifies the DNA binding sites for the transcription factors CREB1 and ATF-2 and the respective genomic region comprising rs2981804 is able to act as a transcriptional regulator in vitro. Intestinal DMBT1 expression is decreased in CD patients carrying the rs2981804 CD risk allele. We identified novel associations of DMBT1 variants with CD susceptibility and discovered a novel functional role of rs2981804 in regulating DMBT1 expression. Our data suggest an important role of DMBT1 in CD pathogenesis.

Acidosis Activates Endoplasmic Reticulum Stress Pathways through GPR4 in Human Vascular Endothelial Cells.

Science.gov (United States)

Dong, Lixue; Krewson, Elizabeth A; Yang, Li V

2017-01-27

Acidosis commonly exists in the tissue microenvironment of various pathophysiological conditions such as tumors, inflammation, ischemia, metabolic disease, and respiratory disease. For instance, the tumor microenvironment is characterized by acidosis and hypoxia due to tumor heterogeneity, aerobic glycolysis (the "Warburg effect"), and the defective vasculature that cannot efficiently deliver oxygen and nutrients or remove metabolic acid byproduct. How the acidic microenvironment affects the function of blood vessels, however, is not well defined. GPR4 (G protein-coupled receptor 4) is a member of the proton-sensing G protein-coupled receptors and it has high expression in endothelial cells (ECs). We have previously reported that acidosis induces a broad inflammatory response in ECs. Acidosis also increases the expression of several endoplasmic reticulum (ER) stress response genes such as CHOP (C/EBP homologous protein) and ATF3 (activating transcription factor 3). In the current study, we have examined acidosis/GPR4- induced ER stress pathways in human umbilical vein endothelial cells (HUVEC) and other types of ECs. All three arms of the ER stress/unfolded protein response (UPR) pathways were activated by acidosis in ECs as an increased expression of phosphorylated eIF2α (eukaryotic initiation factor 2α), phosphorylated IRE1α (inositol-requiring enzyme 1α), and cleaved ATF6 upon acidic pH treatment was observed. The expression of other downstream mediators of the UPR, such as ATF4, ATF3, and spliced XBP-1 (X box-binding protein 1), was also induced by acidosis. Through genetic and pharmacological approaches to modulate the expression level or activity of GPR4 in HUVEC, we found that GPR4 plays an important role in mediating the ER stress response induced by acidosis. As ER stress/UPR can cause inflammation and cell apoptosis, acidosis/GPR4-induced ER stress pathways in ECs may regulate vascular growth and inflammatory response in the acidic microenvironment.

Induction of Activating Transcription Factor 3 Is Associated with Cisplatin Responsiveness in Non–Small Cell Lung Carcinoma Cells

Directory of Open Access Journals (Sweden)

Jair Bar

2016-09-01

Full Text Available Non–small cell lung carcinoma (NSCLC is the most common cause of cancer deaths, with platin-based combination chemotherapy the most efficacious therapies. Gains in overall survival are modest, highlighting the need for novel therapeutic approaches including the development of next-generation platin combination regimens. The goal of this study was to identify novel regulators of platin-induced cytotoxicity as potential therapeutic targets to further enhance platin cytotoxicity. Employing RNA-seq transcriptome analysis comparing two parental NSCLC cell lines Calu6 and H23 to their cisplatin-resistant sublines, Calu6cisR1 and H23cisR1, activating transcription factor 3 (ATF3 was robustly induced in cisplatin-treated parental sensitive cell lines but not their resistant sublines, and in three of six tumors evaluated, but not in their corresponding normal adjacent lung tissue (0/6. Cisplatin-induced JNK activation was a key regulator of this ATF3 induction. Interestingly, in both resistant sublines, this JNK induction was abrogated, and the expression of an activated JNK construct in these cells enhanced both cisplatin-induced cytotoxicity and ATF3 induction. An FDA-approved drug compound screen was employed to identify enhancers of cisplatin cytotoxicity that were dependent on ATF3 gene expression. Vorinostat, a histone deacetylase inhibitor, was identified in this screen and demonstrated synergistic cytotoxicity with cisplatin in both the parental Calu6 and H23 cell lines and importantly in their resistant sublines as well that was dependent on ATF3 expression. Thus, we have identified ATF3 as an important regulator of cisplatin cytotoxicity and that ATF3 inducers in combination with platins are a potential novel therapeutic approach for NSCLC.

Saccharomyces cerevisiae Atf1p is an alcohol acetyltransferase and a thioesterase in vitro.

Science.gov (United States)

Nancolas, Bethany; Bull, Ian D; Stenner, Richard; Dufour, Virginie; Curnow, Paul

2017-06-01

The alcohol-O-acyltransferases are bisubstrate enzymes that catalyse the transfer of acyl chains from an acyl-coenzyme A (CoA) donor to an acceptor alcohol. In the industrial yeast Saccharomyces cerevisiae this reaction produces acyl esters that are an important influence on the flavour of fermented beverages and foods. There is also a growing interest in using acyltransferases to produce bulk quantities of acyl esters in engineered microbial cell factories. However, the structure and function of the alcohol-O-acyltransferases remain only partly understood. Here, we recombinantly express, purify and characterize Atf1p, the major alcohol acetyltransferase from S. cerevisiae. We find that Atf1p is promiscuous with regard to the alcohol cosubstrate but that the acyltransfer activity is specific for acetyl-CoA. Additionally, we find that Atf1p is an efficient thioesterase in vitro with specificity towards medium-chain-length acyl-CoAs. Unexpectedly, we also find that mutating the supposed catalytic histidine (H191) within the conserved HXXXDG active site motif only moderately reduces the thioesterase activity of Atf1p. Our results imply a role for Atf1p in CoA homeostasis and suggest that engineering Atf1p to reduce the thioesterase activity could improve product yields of acetate esters from cellular factories. © 2017 The Authors. Yeast published by John Wiley & Sons, Ltd. © 2017 The Authors. Yeast published by John Wiley & Sons, Ltd.

Development of the C-Band BPM System for ATF2

CERN Document Server

Lyapin, A; Wing, M; Shin, S; Honda, Y; Tauchi, T; Terunuma, N; Heo, A; Kim, E; Kim, K; Ainsworth, R C E; Boogert, S T; Boorman, G; Molloy, S; McCormick, D; Nelson, J; White, G; Ward, D

2010-01-01

The ATF2 international collaboration is intending to demonstrate nanometre beam sizes required for the future Linear Colliders. An essential part of the beam diagnostics needed to achieve that goal is the high resolution cavity beam position monitors (BPMs). In this paper we report on the C-band system consisting of 32 BPMs spread over the whole length of the new ATF2 extraction beamline. We discuss the design of the BPMs and electronics, main features of the DAQ system, and the first operational experience with these BPMs.

In Vitro Anticancer Activity of Phlorofucofuroeckol A via Upregulation of Activating Transcription Factor 3 against Human Colorectal Cancer Cells

Directory of Open Access Journals (Sweden)

Hyun Ji Eo

2016-03-01

Full Text Available Phlorofucofuroeckol A (PFF-A, one of the phlorotannins found in brown algae, has been reported to exert anti-cancer property. However, the molecular mechanism for the anti-cancer effect of PFF-A has not been known. Activating transcription factor 3 (ATF3 has been reported to be associated with apoptosis in colorectal cancer. The present study was performed to investigate the molecular mechanism by which PFF-A stimulates ATF3 expression and apoptosis in human colorectal cancer cells. PFF-A decreased cell viability through apoptosis of human colorectal cancer cells. PFF-A increased ATF3 expression through regulating transcriptional activity. The responsible cis-element for ATF3 transcriptional activation by PFF-A was cAMP response element binding protein (CREB, located between positions −147 and −85 of the ATF3 promoter. Inhibition of p38, c-Jun N-terminal kinases (JNK, glycogen synthase kinase (GSK 3β, and IκB kinase (IKK-α blocked PFF-A-mediated ATF3 expression. ATF3 knockdown by ATF3 siRNA attenuated the cleavage of poly (ADP-ribose polymerase (PARP by PFF-A, while ATF3 overexpression increased PFF-A-mediated cleaved PARP. These results suggest that PFF-A may exert anti-cancer property through inducing apoptosis via the ATF3-mediated pathway in human colorectal cancer cells.

Loading, absorption, and Fokker-Planck calculations for upcoming ICRF experiments on ATF

International Nuclear Information System (INIS)

Shepard, T.D.; Carter, M.D.; Goulding, R.H.; Kwon, M.

1989-01-01

ICRF experiments on ATF at the 100-kW level are planned for the current 1989 operating period. These plans include the 2ω/sub cH/ regime at f/sub RF/ = 28.88 MHz, D(H) at 14.44 MHz, and 4 He( 3 He) and D( 3 He) at 9.63 MHz. ECH target plasmas have n/sub eO/ /approxreverse arrowlt/ 0.15 /times/ 10 20 m/sup /minus/3/ and B = 0.95 T. The density and temperature profiles obtained are broader than those from 1988, owing to recent field error corrections. The values used for target-plasma parameters in the calculations were taken from initial 1989 ATF data. Loading and absorption calculations have been performed using the 3D RF heating code ORION with a helically symmetric equilibrium, and Fokker-Planck calculations were performed using the steady-state code RFTRANS with two velocity dimensions and one spatial dimension. 6 refs., 3 figs

The orphan nuclear receptor NR4A1 (Nur77) regulates oxidative and endoplasmic reticulum stress in pancreatic cancer cells.

Science.gov (United States)

Lee, Syng-Ook; Jin, Un-Ho; Kang, Jeong Han; Kim, Sang Bae; Guthrie, Aaron S; Sreevalsan, Sandeep; Lee, Ju-Seog; Safe, Stephen

2014-04-01

NR4A1 (Nur77, TR3) is an orphan nuclear receptor that is overexpressed in pancreatic cancer and exhibits pro-oncogenic activity. RNA interference of NR4A1 expression in Panc-1 cells induced apoptosis and subsequent proteomic analysis revealed the induction of several markers of endoplasmic reticulum stress, including glucose-related protein 78 (GRP78), CCAAT/enhancer-binding protein-homologous protein (CHOP), and activating transcription factor-4 (ATF-4). Treatment of pancreatic cancer cells with the NR4A1 antagonist 1,1-bis(3'-indolyl)-1-(p-hydroxyphenyl)methane (DIM-C-pPhOH) gave similar results. Moreover, both NR4A1 knockdown and DIM-C-pPhOH induced reactive oxygen species (ROS), and induction of ROS and endoplasmic reticulum stress by these agents was attenuated after cotreatment with antioxidants. Manipulation of NR4A1 expression coupled with gene expression profiling identified a number of ROS metabolism transcripts regulated by NR4A1. Knockdown of one of these transcripts, thioredoxin domain containing 5 (TXNDC5), recapitulated the elevated ROS and endoplasmic reticulum stress; thus, demonstrating that NR4A1 regulates levels of endoplasmic reticulum stress and ROS in pancreatic cancer cells to facilitate cell proliferation and survival. Finally, inactivation of NR4A1 by knockdown or DIM-C-pPhOH decreased TXNDC5, resulting in activation of the ROS/endoplasmic reticulum stress and proapoptotic pathways. The NR4A1 receptor is pro-oncogenic, regulates the ROS/endoplasmic reticulum stress pathways, and inactivation of the receptor represents a novel pathway for inducing cell death in pancreatic cancer. Mol Cancer Res; 12(4); 527-38. ©2014 AACR.

Beam-based alignment at the KEK-ATF damping ring

International Nuclear Information System (INIS)

Woodley, Mark D.; Nelson, Janice; Ross, Marc; Turner, James; Wolski, A.; Kubo, Kiyoshi

2004-01-01

The damping rings of a future linear collider will have demanding alignment and stability requirements in order to achieve the low vertical emittance necessary for high luminosity. The Accelerator Test Facility (ATF) at KEK has successfully demonstrated the vertical emittance below 5 pm that is specified for the GLC/NLC Main Damping Rings. One contribution to this accomplishment has been the use of Beam Based Alignment (BBA) techniques. The mode of operation of the ATF presents particular challenges for BBA, and we describe here how we have deduced the offsets of the BPMs with respect to the quadrupoles. We also discuss a technique that allows for direct measurements of the beam-to-quad offsets

Low pH induces co-ordinate regulation of gene expression in oesophageal cells.

Science.gov (United States)

Duggan, Shane P; Gallagher, William M; Fox, Edward J P; Abdel-Latif, Mohammed M; Reynolds, John V; Kelleher, Dermot

2006-02-01

The development of gastro-oesophageal reflux disease (GORD) is known to be a causative risk factor in the evolution of adenocarcinoma of the oesophagus. The major component of this reflux is gastric acid. However, the impact of low pH on gene expression has not been extensively studied in oesophageal cells. This study utilizes a transcriptomic and bioinformatic approach to assess regulation of gene expression in response to low pH. In more detail, oesophageal adenocarcinoma cell lines were exposed to a range of pH environments. Affymetrix microarrays were used for gene-expression analysis and results were validated using cycle limitation and real-time RT-PCR analysis, as well as northern and western blotting. Comparative promoter transcription factor binding site (TFBS) analysis (MatInspector) of hierarchically clustered gene-expression data was employed to identify the elements which may co-ordinately regulate individual gene clusters. Initial experiments demonstrated maximal induction of EGR1 gene expression at pH 6.5. Subsequent array experimentation revealed significant induction of gene expression from such functional categories as DNA damage response (EGR1-4, ATF3) and cell-cycle control (GADD34, GADD45, p57). Changes in expression of EGR1, EGR3, ATF3, MKP-1, FOSB, CTGF and CYR61 were verified in separate experiments and in a variety of oesophageal cell lines. TFBS analysis of promoters identified transcription factors that may co-ordinately regulate gene-expression clusters, Cluster 1: Oct-1, AP4R; Cluster 2: NF-kB, EGRF; Cluster 3: IKRS, AP-1F. Low pH has the ability to induce genes and pathways which can provide an environment suitable for the progression of malignancy. Further functional analysis of the genes and clusters identified in this low pH study is likely to lead to new insights into the pathogenesis and therapeutics of GORD and oesophageal cancer.

High-brightness electron beam diagnostics at the ATF

International Nuclear Information System (INIS)

Wang, X.J.; Ben-Zvi, I.

1996-01-01

The Brookhaven Accelerator Test Facility (ATF) is a dedicated user facility for accelerator physicists. Its design is optimized to explore laser acceleration and coherent radiation production. To characterize the low-emittance, picoseconds long electron beam produced by the ATF's photocathode RF gun, we have installed electron beam profile monitors for transverse emittance measurement, and developed a new technique to measure electron beam pulse length by chirping the electron beam energy. We have also developed a new technique to measure the ps slice emittance of a 10 ps long electron beam. Stripline beam position monitors were installed along the beam to monitor the electron beam position and intensity. A stripline beam position monitor was also used to monitor the timing jitter between the RF system and laser pulses. Transition radiation was used to measure electron beam energy, beam profile and electron beam bunch length

A first glance at the initial ATF experimental results

International Nuclear Information System (INIS)

Carreras, B.A.; Dominguez, N.; Leboeuf, J.N.; Lynch, V.E.; Charlton, L.A.

1989-05-01

In the initial phase of ATF operation, the plasma minor radius and the edge rotational transform were reduced by field errors. This caused an effective change of the magnetic configuration: it improved the stability properties but worsened the equilibrium properties. The threshold for the second stability regime was lowered to β 0 /approximately/ 1.5%. Experimental profile data are compatible with operation in the second stability regime, and the achieved beta values, β 0 /approximately/ 3%, are well beyond the theoretically calculated threshold. Magnetic fluctuation measurements showed the effects of beta self-stabilization. They are in reasonable agreement with the predictions of the theory and support the evidence that ATF has already operated in the second stability regime. 24 refs., 20 figs., 1 tab

ATF4, A Novel Mediator of the Anabolic Actions of PTH on Bone

Science.gov (United States)

2012-01-01

poster) A5. Xiao G. Critical role of activating transcription factor 4 in parathyroid hormone-mediated bone formation. Military Health Research...C, Pittsburgh, Pennsylvania 15240. E-mail: xiaog@upmc.edu. This work was supported by National Institutes of Health Grants DK072230 (to G.X.) and...Ahn JD, Takeda S, Starbuck M, Yang X, Liu X, Kondo H, Richards WG, Bannon TW, Noda M, Clement K, Vaisse C, Karsenty G 2005 Leptin regulation of bone

The Drosophila MAPK p38c regulates oxidative stress and lipid homeostasis in the intestine.

Directory of Open Access Journals (Sweden)

Sveta Chakrabarti

2014-09-01

Full Text Available The p38 mitogen-activated protein (MAP kinase signaling cassette has been implicated in stress and immunity in evolutionarily diverse species. In response to a wide variety of physical, chemical and biological stresses p38 kinases phosphorylate various substrates, transcription factors of the ATF family and other protein kinases, regulating cellular adaptation to stress. The Drosophila genome encodes three p38 kinases named p38a, p38b and p38c. In this study, we have analyzed the role of p38c in the Drosophila intestine. The p38c gene is expressed in the midgut and upregulated upon intestinal infection. We showed that p38c mutant flies are more resistant to infection with the lethal pathogen Pseudomonas entomophila but are more susceptible to the non-pathogenic bacterium Erwinia carotovora 15. This phenotype was linked to a lower production of Reactive Oxygen Species (ROS in the gut of p38c mutants, whereby the transcription of the ROS-producing enzyme Duox is reduced in p38c mutant flies. Our genetic analysis shows that p38c functions in a pathway with Mekk1 and Mkk3 to induce the phosphorylation of Atf-2, a transcription factor that controls Duox expression. Interestingly, p38c deficient flies accumulate lipids in the intestine while expressing higher levels of antimicrobial peptide and metabolic genes. The role of p38c in lipid metabolism is mediated by the Atf3 transcription factor. This observation suggests that p38c and Atf3 function in a common pathway in the intestine to regulate lipid metabolism and immune homeostasis. Collectively, our study demonstrates that p38c plays a central role in the intestine of Drosophila. It also reveals that many roles initially attributed to p38a are in fact mediated by p38c.

The Drosophila MAPK p38c regulates oxidative stress and lipid homeostasis in the intestine.

Science.gov (United States)

Chakrabarti, Sveta; Poidevin, Mickaël; Lemaitre, Bruno

2014-09-01

The p38 mitogen-activated protein (MAP) kinase signaling cassette has been implicated in stress and immunity in evolutionarily diverse species. In response to a wide variety of physical, chemical and biological stresses p38 kinases phosphorylate various substrates, transcription factors of the ATF family and other protein kinases, regulating cellular adaptation to stress. The Drosophila genome encodes three p38 kinases named p38a, p38b and p38c. In this study, we have analyzed the role of p38c in the Drosophila intestine. The p38c gene is expressed in the midgut and upregulated upon intestinal infection. We showed that p38c mutant flies are more resistant to infection with the lethal pathogen Pseudomonas entomophila but are more susceptible to the non-pathogenic bacterium Erwinia carotovora 15. This phenotype was linked to a lower production of Reactive Oxygen Species (ROS) in the gut of p38c mutants, whereby the transcription of the ROS-producing enzyme Duox is reduced in p38c mutant flies. Our genetic analysis shows that p38c functions in a pathway with Mekk1 and Mkk3 to induce the phosphorylation of Atf-2, a transcription factor that controls Duox expression. Interestingly, p38c deficient flies accumulate lipids in the intestine while expressing higher levels of antimicrobial peptide and metabolic genes. The role of p38c in lipid metabolism is mediated by the Atf3 transcription factor. This observation suggests that p38c and Atf3 function in a common pathway in the intestine to regulate lipid metabolism and immune homeostasis. Collectively, our study demonstrates that p38c plays a central role in the intestine of Drosophila. It also reveals that many roles initially attributed to p38a are in fact mediated by p38c.

An FPGA-based Bunch-by-Bunch Position and Angle Feedback System at ATF2

CERN Document Server

Christian, G B; Bett, D R; Burrows, P N; Constance, B; Davis, M R; Gerbershagen, A; Perry, C; Resta Lopez, J

2011-01-01

The FONT5 intra-train feedback system serves as a prototype for an interaction point beam-based feedback system for future electron-positron colliders, such as the International Linear Collider. The system has been tested on the KEK Accelerator Test Facility (ATF) and is deployed to stabilise the beam orbit at the ATF2. The goal of this system is to correct both position and angle jitter in the vertical plane, providing stability of ~1 micron at the entrance to the ATF2 final-focus system. The system comprises three stripline beam position monitors (BPMs) and two stripline kickers, custom low-latency analogue front-end BPM processors, a custom FPGA-based digital processing board with fast ADCs, and custom kicker-drive amplifiers. An overview of the hardware, and the latest results from beam tests at ATF2, will be presented. The total latency of the system with coupled position and angle feedback loops operating simultaneously was measured to be approximately 140 ns. The greatest degree of correction observed ...

Initial high-power testing of the ATF [Advanced Toroidal Facility] ECH [electron cyclotron heating] system

International Nuclear Information System (INIS)

White, T.L.; Bigelow, T.S.; Kimrey, H.D. Jr.

1987-01-01

The Advanced Toroidal Facility (ATF) is a moderate aspect ratio torsatron that will utilize 53.2 GHz 200 kW Electron Cyclotron Heating (ECH) to produce nearly current-free target plasmas suitable for subsequent heating by strong neutral beam injection. The initial configuration of the ECH system from the gyrotron to ATF consists of an optical arc detector, three bellows, a waveguide mode analyzer, two TiO 2 mode absorbers, two 90 0 miter bends, two waveguide pumpouts, an insulating break, a gate valve, and miscellaneous straight waveguide sections feeding a launcher radiating in the TE 02 mode. Later, a focusing Vlasov launcher will be added to beam the ECH power to the saddle point in ATF magnetic geometry for optimum power deposition. The ECH system has several unique features; namely, the entire ECH system is evacuated, the ECH system is broadband, forward power is monitored by a newly developed waveguide mode analyzer, phase correcting miter bends will be employed, and the ECH system will be capable of operating short pulse to cw. Initial high-power tests show that the overall system efficiency is 87%. The waveguide mode analyzer shows that the gyrotron mode output consists of 13% TE 01 , 82.6% TE 02 , 2.5% TE 03 , and 1.9% TE 04 . 4 refs

Intervention of electroacupuncture on spinal p38 MAPK/ATF-2/VR-1 pathway in treating inflammatory pain induced by CFA in rats.

Science.gov (United States)

Fang, Jian-Qiao; Du, Jun-Ying; Liang, Yi; Fang, Jun-Fan

2013-03-22

Previous studies have demonstrated that p38 MAPK signal transduction pathway plays an important role in the development and maintenance of inflammatory pain. Electroacupuncture (EA) can suppress the inflammatory pain. However, the relationship between EA effect and p38 MAPK signal transduction pathway in inflammatory pain remains poorly understood. It is our hypothesis that p38 MAPK/ATF-2/VR-1 and/or p38 MAPK/ATF-2/COX-2 signal transduction pathway should be activated by inflammatory pain in CFA-injected model. Meanwhile, EA may inhibit the activation of p38 MAPK signal transduction pathway. The present study aims to investigate that anti-inflammatory and analgesic effect of EA and its intervention on the p38 MAPK signal transduction pathway in a rat model of inflammatory pain. EA had a pronounced anti-inflammatory and analgesic effect on CFA-induced chronic inflammatory pain in rats. EA could quickly raise CFA-rat's paw withdrawal thresholds (PWTs) and maintain good and long analgesic effect, while it subdued the ankle swelling of CFA rats only at postinjection day 14. EA could down-regulate the protein expressions of p-p38 MAPK and p-ATF-2, reduced the numbers of p-p38 MAPK-IR cells and p-ATF-2-IR cells in spinal dorsal horn in CFA rats, inhibited the expressions of both protein and mRNA of VR-1, but had no effect on the COX-2 mRNA expression. The present study indicates that inhibiting the activation of spinal p38 MAPK/ATF-2/VR-1 pathway may be one of the main mechanisms via central signal transduction pathway in the process of anti-inflammatory pain by EA in CFA rats.

Measurements of flux surfaces in the ATF torsatron

International Nuclear Information System (INIS)

England, A.C.; Colchin, R.J.; Harris, J.H.; Hillis, D.L.; Jernigan, T.C.; Anderson, F.S.B.

1989-01-01

Flux surfaces in the advanced toroidal facility (ATF) torsatron have been measured using electron-beam techniques. The beam was injected toroidally and impinged on a phosphor-coated screen located ∼ 180 degrees from the gun. The gun was mounted on a drive mechanism that enabled the beam to scan the entire cross section of the last closed flux surface in ATF. The screen material was st. steel, coated with ZnO:Zn (P-15 or P-24) phosphor, and the transparency was ∼ 90%. The emitted light was detected with an image-intensified CCD camera that viewed the mesh through a nearby port. The images were displayed directly on a TV monitor and stored on video tape. Frames from the video tape were transferred to a computer, where the image was enhanced and transformed to remove spatial distortions due to the lens and the viewing angle of the camera

SAMS: The synchronization and monitoring system for ATF [Advanced Toroidal Facility] data acquisition

International Nuclear Information System (INIS)

Greenwood, D.E.

1987-01-01

SAMS performs much of the synchronization of the distributed data acquisition system for the Advanced Toroidal Facility (ATF). SAMS is responsible for propagating shot information and managing te data system directories and logical names. This paper describes how SAMS communicates with other processes, both within the VAX cluster that supports most of the ATF data acquisition and on VAXes that are connected to the cluster via DECnet. 3 refs

Multi Optical Transition Radiation System for ATF2

International Nuclear Information System (INIS)

Alabau-Gonzalvo, Javier

2012-01-01

In this paper we describe the design, installation and first calibration tests of a Multi Optical Transition Radiation System in the beam diagnostic section of the Extraction (EXT) line of ATF2, close to the multi wire scanner system. This system will be a valuable tool for measuring beam sizes and emittances coming from the ATF Damping Ring. With an optical resolution of about 2 (micro)m an original OTR design (OTR1X) located after the septum at the entrance of the EXT line demonstrated the ability to measure a 5.5 (micro)m beam size in one beam pulse and to take many fast measurements. This gives the OTR the ability to measure the beam emittance with high statistics, giving a low error and a good understanding of emittance jitter. Furthermore the nearby wire scanners will be a definitive test of the OTR as a beam emittance diagnostic device. The multi-OTR system design proposed here is based on the existing OTR1X.

Hepatocyte DACH1 Is Increased in Obesity via Nuclear Exclusion of HDAC4 and Promotes Hepatic Insulin Resistance

Directory of Open Access Journals (Sweden)

Lale Ozcan

2016-06-01

Full Text Available Defective insulin signaling in hepatocytes is a key factor in type 2 diabetes. In obesity, activation of calcium/calmodulin-dependent protein kinase II (CaMKII in hepatocytes suppresses ATF6, which triggers a PERK-ATF4-TRB3 pathway that disrupts insulin signaling. Elucidating how CaMKII suppresses ATF6 is therefore essential to understanding this insulin resistance pathway. We show that CaMKII phosphorylates and blocks nuclear translocation of histone deacetylase 4 (HDAC4. As a result, HDAC4-mediated SUMOylation of the corepressor DACH1 is decreased, which protects DACH1 from proteasomal degradation. DACH1, together with nuclear receptor corepressor (NCOR, represses Atf6 transcription, leading to activation of the PERK-TRB3 pathway and defective insulin signaling. DACH1 is increased in the livers of obese mice and humans, and treatment of obese mice with liver-targeted constitutively nuclear HDAC4 or DACH1 small hairpin RNA (shRNA increases ATF6, improves hepatocyte insulin signaling, and protects against hyperglycemia and hyperinsulinemia. Thus, DACH1-mediated corepression in hepatocytes emerges as an important link between obesity and insulin resistance.

Novel method of aligning ATF-1 coils

International Nuclear Information System (INIS)

Rome, J.A.; Harris, J.H.; Neilson, G.H.; Jernigan, T.C.

1983-08-01

The coils for the Advanced Toroidal Facility (ATF-1) torsatron may be easily aligned before the machine is placed under vacuum. This is done by creating nulls in the magnetic field by energizing the coils in various configurations. All of the nulls in vertical bar B vector vertical bar occur on the z-axis. When the nulls coincide, the coils are properly aligned

The transcription factor Jdp2 controls bone homeostasis and antibacterial immunity by regulating osteoclast and neutrophil differentiation.

Science.gov (United States)

Maruyama, Kenta; Fukasaka, Masahiro; Vandenbon, Alexis; Saitoh, Tatsuya; Kawasaki, Takumi; Kondo, Takeshi; Yokoyama, Kazunari K; Kidoya, Hiroyasu; Takakura, Nobuyuki; Standley, Daron; Takeuchi, Osamu; Akira, Shizuo

2012-12-14

Jdp2 is an AP-1 family transcription factor that regulates the epigenetic status of histones. Previous in vitro studies revealed that Jdp2 is involved in osteoclastogenesis. However, the roles of Jdp2 in vivo and its pleiotropic functions are largely unknown. Here we generated Jdp2(-/-) mice and discovered its crucial roles not only in bone metabolism but also in differentiation of neutrophils. Jdp2(-/-) mice exhibited osteopetrosis resulting from impaired osteoclastogenesis. Jdp2(-/-) neutrophils were morphologically normal but had impaired surface expression of Ly6G, bactericidal function, and apoptosis. We also found that ATF3 was an inhibitor of neutrophil differentiation and that Jdp2 directly suppresses its expression via inhibition of histone acetylation. Strikingly, Jdp2(-/-) mice were highly susceptible to Staphylococcus aureus and Candida albicans infection. Thus, Jdp2 plays pivotal roles in in vivo bone homeostasis and host defense by regulating osteoclast and neutrophil differentiation. Copyright © 2012 Elsevier Inc. All rights reserved.

RIA simulation tests using driver tube for ATF cladding

Energy Technology Data Exchange (ETDEWEB)

Cinbiz, Mahmut N. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Brown, N. R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lowden, R. R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Linton, K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Terrani, K. A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-07-01

Pellet-cladding mechanical interaction (PCMI) is a potential failure mechanism for accident-tolerant fuel (ATF) cladding candidates during a reactivity-initiated accident (RIA). This report summarizes Fiscal Year (FY) 2017 research activities that were undertaken to evaluate the PCMI-like hoop-strain-driven mechanical response of ATF cladding candidates. To achieve various RIA-like conditions, a modified-burst test (MBT) device was developed to produce different mechanical pulses. The calibration of the MBT instrument was accomplished by performing mechanical tests on unirradiated Generation-I iron-chromium-aluminum (FeCrAl) alloy samples. Shakedown tests were also conducted in both FY 2016 and FY 2017 using unirradiated hydrided ZIRLO™ tube samples. This milestone report focuses on testing of ATF materials, but the benchmark tests with hydrided ZIRLO™ tube samples are documented in a recent journal article.a For the calibration and benchmark tests, the hoop strain was monitored using strain gauges attached to the sample surface in the hoop direction. A novel digital image correlation (DIC) system composed of a single high-speed camera and an array of six mirrors was developed for the MBT instrument to better resolve the failure behavior of samples and to provide useful data for validation of high-fidelity modeling and simulation tools. The DIC system enable a 360° view of a sample’s outer surface. This feature was added to the instrument to determine the precise failure location on a sample’s surface for strain predictions. The DIC system was tested on several silicon carbide fiber/silicon carbide matrix (SiC/SiC) composite tube samples at various pressurization rates of the driver tube (which correspond to the strain rates for the samples). The hoop strains for various loading conditions were determined for the SiC/SiC composite tube samples. Future work is planned to enhance understanding of the failure behavior of the ATF cladding candidates of age

Torsion of surface plate of the active support table for the ATF damping ring

International Nuclear Information System (INIS)

Takeuchi, Yasunori; Takeda, Shigeru; Kudo, Kikuo; Funahashi, Yoshisato; Kanazawa, Yasunori.

1996-01-01

Distortion of the surface plate of active support table was measured using precise tiltmeters. It is found that the surface plate is twisted when the temperature changes. The effect of this phenomenon is much smaller than the alignment tolerance of the ATF damping ring if the room temperature is controlled within 0.4degC. However, it is not negligible in the linear collider case. (author)

A Taiwanese Propolis Derivative Induces Apoptosis through Inducing Endoplasmic Reticular Stress and Activating Transcription Factor-3 in Human Hepatoma Cells

Directory of Open Access Journals (Sweden)

Fat-Moon Suk

2013-01-01

Full Text Available Activating transcription factor-(ATF- 3, a stress-inducible transcription factor, is rapidly upregulated under various stress conditions and plays an important role in inducing cancer cell apoptosis. NBM-TP-007-GS-002 (GS-002 is a Taiwanese propolin G (PPG derivative. In this study, we examined the antitumor effects of GS-002 in human hepatoma Hep3B and HepG2 cells in vitro. First, we found that GS-002 significantly inhibited cell proliferation and induced cell apoptosis in dose-dependent manners. Several main apoptotic indicators were found in GS-002-treated cells, such as the cleaved forms of caspase-3, caspase-9, and poly(ADP-ribose polymerase (PARP. GS-002 also induced endoplasmic reticular (ER stress as evidenced by increases in ER stress-responsive proteins including glucose-regulated protein 78 (GRP78, growth arrest- and DNA damage-inducible gene 153 (GADD153, phosphorylated eukaryotic initiation factor 2α (eIF2α, phosphorylated protein endoplasmic-reticular-resident kinase (PERK, and ATF-3. The induction of ATF-3 expression was mediated by mitogen-activated protein kinase (MAPK signaling pathways in GS-002-treated cells. Furthermore, we found that GS-002 induced more cell apoptosis in ATF-3-overexpressing cells. These results suggest that the induction of apoptosis by the propolis derivative, GS-002, is partially mediated through ER stress and ATF-3-dependent pathways, and GS-002 has the potential for development as an antitumor drug.

Variants near DMRT1, TERT and ATF7IP are associated with testicular germ cell cancer

Science.gov (United States)

Turnbull, Clare; Rapley, Elizabeth A.; Seal, Sheila; Pernet, David; Renwick, Anthony; Hughes, Deborah; Ricketts, Michelle; Linger, Rachel; Nsengimana, Jeremie; Deloukas, Panagiotis; Huddart, Robert A.; Bishop, D Timothy; Easton, Douglas F.; Stratton, Michael R.; Rahman, Nazneen

2013-01-01

We conducted a genome-wide association study for testicular germ cell tumor genotyping 298,782 SNPs in 979 cases and 4,947 controls from the UK and replicating associations in a further 664 cases and 3,456 controls. We identified three novel susceptibility loci, two of which include genes that are involved in telomere regulation. We identified two independent signals within the TERT-CLPTM1L locus on chromosome 5 which has been associated with multiple other cancers (rs4635969, OR=1.54 (95%CI 1.33-1.79), P=1.14×10−23 and rs2736100, OR 1.33 (1.18-1.50) P=7.55 ×10−15). We also identified a locus on chromosome 12 (rs2900333, OR=1.27 (95%CI 1.12-1.44), P=6.16×10−10) that contains ATF7IP, a regulator of TERT expression. Finally we identified a locus on chromosome 9 (rs755383, OR=1.37 (95%CI 1.21-1.55), P=1.12×10−23) containing the sex determination gene DMRT1, which has been linked with teratoma susceptibility in mice. PMID:20543847

Studies of plasma performance and transport in the advanced toroidal facility (ATF)

International Nuclear Information System (INIS)

Neilson, G.H.; Bigelow, T.S.; Carreras, B.A.

1989-01-01

An overview of recent ATF experimental results and program plans is presented, with emphasis on the role of magnetic configuration controls in transport studies. The ATF operating space is bounded by a density limit that effectively sets a limit on the energy confinement time τ E . Although this limit is not solely due to impurities, it has recently been raised by improved cleanliness following titanium gettering. This has led to collapse-free neutral beam injection (NBI) discharges with global τ E ∼ 16 ms. Preliminary experiments show that stored energy and bootstrap current are sensitive to details of the magnetic configuration. 13 refs., 8 figs

Overview of the ATF [Advanced Toroidal Facility] Program

International Nuclear Information System (INIS)

Lyon, J.F.; Aceto, S.C.; Anderson, F.S.B.

1989-01-01

Initial operation of ATF showed narrow pressure profiles and second stability behavior at lower beta than expected and revealed uncompensated dipoles in the HF winding leads that have since been corrected. Energy confinement times obtained with neutral beam injection and electron cyclotron heating roughly follow the LHD scaling. However, a plasma collapse is observed with NBI 6 refs., 9 figs

Wire alignment system for ATF LINAC

International Nuclear Information System (INIS)

Hayano, H.; Takeda, S.; Matsumoto, H.; Matsui, T.

1994-01-01

A wire based alignment system is adopted to make less than 40μm precision alignment for injector linac of Accelerator Test Facility (ATF). The system consists of two stretched SUS wires, pickup coils and active mover stages. The position of pickup coils in a mount which will be installed into LINAC stages is set to the calculated wire position prior to installation. All of LINAC stages are then moved to keep the calculated position by the active mover. The test results of wire position detection in a long term are described. (author)

Regulation of Cancer Cell Responsiveness to Ionizing Radiation Treatment by Cyclic AMP Response Element Binding Nuclear Transcription Factor

Directory of Open Access Journals (Sweden)

Francesca D’Auria

2017-05-01

Full Text Available Cyclic AMP response element binding (CREB protein is a member of the CREB/activating transcription factor (ATF family of transcription factors that play an important role in the cell response to different environmental stimuli leading to proliferation, differentiation, apoptosis, and survival. A number of studies highlight the involvement of CREB in the resistance to ionizing radiation (IR therapy, demonstrating a relationship between IR-induced CREB family members’ activation and cell survival. Consistent with these observations, we have recently demonstrated that CREB and ATF-1 are expressed in leukemia cell lines and that low-dose radiation treatment can trigger CREB activation, leading to survival of erythro-leukemia cells (K562. On the other hand, a number of evidences highlight a proapoptotic role of CREB following IR treatment of cancer cells. Since the development of multiple mechanisms of resistance is one key problem of most malignancies, including those of hematological origin, it is highly desirable to identify biological markers of responsiveness/unresponsiveness useful to follow-up the individual response and to adjust anticancer treatments. Taking into account all these considerations, this mini-review will be focused on the involvement of CREB/ATF family members in response to IR therapy, to deepen our knowledge of this topic, and to pave the way to translation into a therapeutic context.

Blimp-1 controls plasma cell function through regulation of immunoglobulin secretion and the unfolded protein response

Science.gov (United States)

Tellier, Julie; Shi, Wei; Minnich, Martina; Liao, Yang; Crawford, Simon; Smyth, Gordon K; Kallies, Axel; Busslinger, Meinrad; Nutt, Stephen L

2015-01-01

Plasma cell differentiation requires silencing of B cell transcription, while establishing antibody-secretory function and long-term survival. The transcription factors Blimp-1 and IRF4 are essential for plasma cell generation, however their function in mature plasma cells has remained elusive. We have found that while IRF4 was essential for plasma cell survival, Blimp-1 was dispensable. Blimp-1-deficient plasma cells retained their transcriptional identity, but lost the ability to secrete antibody. Blimp-1 regulated many components of the unfolded protein response (UPR), including XBP-1 and ATF6. The overlap of Blimp-1 and XBP-1 function was restricted to the UPR, with Blimp-1 uniquely regulating mTOR activity and plasma cell size. Thus, Blimp-1 is required for the unique physiological capacity of plasma cells that enables the secretion of protective antibody. PMID:26779600

Arabidopsis MAP Kinase 4 regulates gene expression via transcription factor release in the nucleus

DEFF Research Database (Denmark)

Qiu, Jin-Long; Fiil, Berthe Katrine; Petersen, Klaus

2008-01-01

kinase 4 (MPK4) exists in nuclear complexes with the WRKY33 transcription factor. This complex depends on the MPK4 substrate MKS1. Challenge with Pseudomonas syringae or flagellin leads to the activation of MPK4 and phosphorylation of MKS1. Subsequently, complexes with MKS1 and WRKY33 are released from...... MPK4, and WRKY33 targets the promoter of PHYTOALEXIN DEFICIENT3 (PAD3) encoding an enzyme required for the synthesis of antimicrobial camalexin. Hence, wrky33 mutants are impaired in the accumulation of PAD3 mRNA and camalexin production upon infection. That WRKY33 is an effector of MPK4 is further...... supported by the suppression of PAD3 expression in mpk4-wrky33 double mutant backgrounds. Our data establish direct links between MPK4 and innate immunity and provide an example of how a plant MAP kinase can regulate gene expression by releasing transcription factors in the nucleus upon activation....

ATF3 expression improves motor function in the ALS mouse model by promoting motor neuron survival and retaining muscle innervation.

Science.gov (United States)

Seijffers, Rhona; Zhang, Jiangwen; Matthews, Jonathan C; Chen, Adam; Tamrazian, Eric; Babaniyi, Olusegun; Selig, Martin; Hynynen, Meri; Woolf, Clifford J; Brown, Robert H

2014-01-28

ALS is a fatal neurodegenerative disease characterized by a progressive loss of motor neurons and atrophy of distal axon terminals in muscle, resulting in loss of motor function. Motor end plates denervated by axonal retraction of dying motor neurons are partially reinnervated by remaining viable motor neurons; however, this axonal sprouting is insufficient to compensate for motor neuron loss. Activating transcription factor 3 (ATF3) promotes neuronal survival and axonal growth. Here, we reveal that forced expression of ATF3 in motor neurons of transgenic SOD1(G93A) ALS mice delays neuromuscular junction denervation by inducing axonal sprouting and enhancing motor neuron viability. Maintenance of neuromuscular junction innervation during the course of the disease in ATF3/SOD1(G93A) mice is associated with a substantial delay in muscle atrophy and improved motor performance. Although disease onset and mortality are delayed, disease duration is not affected. This study shows that adaptive axonal growth-promoting mechanisms can substantially improve motor function in ALS and importantly, that augmenting viability of the motor neuron soma and maintaining functional neuromuscular junction connections are both essential elements in therapy for motor neuron disease in the SOD1(G93A) mice. Accordingly, effective protection of optimal motor neuron function requires restitution of multiple dysregulated cellular pathways.

Operational Experiences Tuning the ATF2 Final Focus Optics Towards Obtaining a 37nm Electron Beam IP Spot Size

CERN Document Server

White, Glen; Woodley, Mark; Bai, Sha; Bambade, Philip; Renier, Yves; Bolzon, Benoit; Kamiya, Yoshio; Komamiya, Sachio; Oroku, Masahiro; Yamaguchi, Yohei; Yamanaka, Takashi; Kubo, Kiyoshi; Kuroda, Shigeru; Okugi, Toshiyuki; Tauchi, Toshiaki; Marin, Eduardo

2010-01-01

The primary aim of the ATF2 research accelerator is to test a scaled version of the final focus optics planned for use in next-generation linear lepton colliders. ATF2 consists of a 1.3 GeV linac, damping ring providing lowemittance electron beams (<12pm in the vertical plane), extraction line and final focus optics. The design details of the final focus optics and implementation at ATF2 are presented elsewhere. The ATF2 accelerator is currently being commissioned, with a staged approach to achieving the design IP spot size. It is expected that as we implement more demanding optics and reduce the vertical beta function at the IP, the tuning becomes more difficult and takes longer. We present here a description of the implementation of the tuning procedures and describe operational experiences and performances

Regulation of eukaryotic initiation factor 4AII by MyoD during murine myogenic cell differentiation.

Directory of Open Access Journals (Sweden)

Gabriela Galicia-Vázquez

Full Text Available Gene expression during muscle cell differentiation is tightly regulated at multiple levels, including translation initiation. The PI3K/mTOR signalling pathway exerts control over protein synthesis by regulating assembly of eukaryotic initiation factor (eIF 4F, a heterotrimeric complex that stimulates recruitment of ribosomes to mRNA templates. One of the subunits of eIF4F, eIF4A, supplies essential helicase function during this phase of translation. The presence of two cellular eIF4A isoforms, eIF4AI and eIF4AII, has long thought to impart equivalent functions to eIF4F. However, recent experiments have alluded to distinct activities between them. Herein, we characterize distinct regulatory mechanisms between the eIF4A isoforms during muscle cell differentiation. We find that eIF4AI levels decrease during differentiation whereas eIF4AII levels increase during myofiber formation in a MyoD-dependent manner. This study characterizes a previously undefined mechanism for eIF4AII regulation in differentiation and highlights functional differences between eIF4AI and eIF4AII. Finally, RNAi-mediated alterations in eIF4AI and eIF4AII levels indicate that the myogenic process can tolerate short term reductions in eIF4AI or eIF4AII levels, but not both.

G-actin sequestering protein thymosin-β4 regulates the activity of myocardin-related transcription factor.

Science.gov (United States)

Morita, Tsuyoshi; Hayashi, Ken'ichiro

2013-08-02

Myocardin-related transcription factors (MRTFs) are robust coactivators of serum response factor (SRF). MRTFs contain three copies of the RPEL motif at their N-terminus, and they bind to monomeric globular actin (G-actin). Previous studies illustrate that G-actin binding inhibits MRTF activity by preventing the MRTFs nuclear accumulation. In the living cells, the majority of G-actin is sequestered by G-actin binding proteins that prevent spontaneous actin polymerization. Here, we demonstrate that the most abundant G-actin sequestering protein thymosin-β4 (Tβ4) was involved in the regulation of subcellular localization and activity of MRTF-A. Tβ4 competed with MRTF-A for G-actin binding; thus, interfering with G-actin-MRTF-A complex formation. Tβ4 overexpression induced the MRTF-A nuclear accumulation and activation of MRTF-SRF signaling. The activation rate of MRTF-A by the Tβ4 mutant L17A, whose affinity for G-actin is very low, was lower than that by wild-type Tβ4. In contrast, the β-actin mutant 3DA, which has a lower affinity for Tβ4, more effectively suppressed MRTF-A activity than wild-type β-actin. Furthermore, ectopic Tβ4 increased the endogenous expression of SRF-dependent actin cytoskeletal genes. Thus, Tβ4 is an important MRTF regulator that controls the G-actin-MRTFs interaction. Copyright © 2013 Elsevier Inc. All rights reserved.

Performance Comparison of Different System Identification Algorithms for FACET and ATF2

CERN Document Server

Pfingstner, J; Schulte, D

2013-01-01

Good system knowledge is an essential ingredient for the operation of modern accelerator facilities. For example, beam-based alignment algorithms and orbit feedbacks rely strongly on a precise measurement of the orbit response matrix. The quality of the measurement of this matrix can be improved over time by statistically combining the effects of small system excitations with the help of system identification algorithms. These small excitations can be applied in a parasitic mode without stopping the accelerator operation (on-line). In this work, different system identification algorithms are used in simulation studies for the response matrix measurement at ATF2. The results for ATF2 are finally compared with the results for FACET, latter originating from an earlier work.

An analytical method for calculating stresses and strains of ATF cladding based on thick walled theory

Energy Technology Data Exchange (ETDEWEB)

Kim, Dong Hyun; Kim, Hak Sung [Hanyang University, Seoul (Korea, Republic of); Kim, Hyo Chan; Yang, Yong Sik; In, Wang kee [KAERI, Daejeon (Korea, Republic of)

2016-05-15

In this paper, an analytical method based on thick walled theory has been studied to calculate stress and strain of ATF cladding. In order to prescribe boundary conditions of the analytical method, two algorithms were employed which are called subroutine 'Cladf' and 'Couple' of FRACAS, respectively. To evaluate the developed method, equivalent model using finite element method was established and stress components of the method were compared with those of equivalent FE model. One of promising ATF concepts is the coated cladding, which take advantages such as high melting point, a high neutron economy, and low tritium permeation rate. To evaluate the mechanical behavior and performance of the coated cladding, we need to develop the specified model to simulate the ATF behaviors in the reactor. In particular, the model for simulation of stress and strain for the coated cladding should be developed because the previous model, which is 'FRACAS', is for one body model. The FRACAS module employs the analytical method based on thin walled theory. According to thin-walled theory, radial stress is defined as zero but this assumption is not suitable for ATF cladding because value of the radial stress is not negligible in the case of ATF cladding. Recently, a structural model for multi-layered ceramic cylinders based on thick-walled theory was developed. Also, FE-based numerical simulation such as BISON has been developed to evaluate fuel performance. An analytical method that calculates stress components of ATF cladding was developed in this study. Thick-walled theory was used to derive equations for calculating stress and strain. To solve for these equations, boundary and loading conditions were obtained by subroutine 'Cladf' and 'Couple' and applied to the analytical method. To evaluate the developed method, equivalent FE model was established and its results were compared to those of analytical model. Based on the

A beam-profile monitor for the BNL Accelerator Test Facility (ATF)

International Nuclear Information System (INIS)

Russell, D.P.; McDonald, K.T.

1989-01-01

A beam-profile monitor has been designed to diagnose the 5-MeV high-brightness electron beam from the rf gun of the BNL Accelerator Test Facility (ATF). The monitor consists of a phosphor screen viewed by a CCD camera. The video images are digitized and stored by a framegrabber and analyzed by an IBM PC-AT to extract the emittance. Details of the hardware configuration are presented, along with the spatial resolution of the system measured as a function of phosphor-screen thickness. The strategies which will be used to measure the transverse and longitudinal emittances are briefly mentioned. The system should be capable of measuring a transverse geometric emittance of around 1 mm-mrad, as will be typical of the ATF beam. 6 refs., 2 figs

Plans for improvements to the ATF ECH system

International Nuclear Information System (INIS)

Bigelow, T.S.; Goldfinger, R.C.; Murakami, M.; Schaich, C.R.; Wilgen, J.B.

1993-01-01

The Advanced Toroidal Facility (ATF) stellarator experiment at Oak Ridge National Laboratory (ORNL) uses electron cyclotron waves for plasma formation and heating. Although the existing systems are quite reliable and produce acceptable plasmas, a few deficiencies should be corrected. Therefore, several possible upgrades to the electron cyclotron heating (ECH) systems have been planned. Some of the desirable changes are (1) improving the launcher to make power deposition in the plasma more centralized, (2) improving the gyrotron power waveform monitoring diagnostics, (3) building a high-field launch system for higher density operation at 53-GHz (4) building a separate transmission line for the 35-GHz gyrotron, and (5) installing a higher frequency, higher power (84- or 110-GHz) gyrotron system for improved plasma density and temperature capability. This paper discusses options for these improvements and conceptual designs. (orig.)

Pancreatic β-cells activate a JunB/ATF3-dependent survival pathway during inflammation

DEFF Research Database (Denmark)

Gurzov, E N; Barthson, J; Marhfour, I

2012-01-01

Destruction of insulin-producing pancreatic β-cells by local autoimmune inflammation is a hallmark of type 1 diabetes. Histochemical analysis of pancreases from non-obese diabetic mice indicated activation of the transcription factor JunB/AP-1 (activator protein-1) after autoimmune infiltration......-cells and human islet cells against pro-inflammatory mediators. These results were confirmed in genetically modified islets derived from Ubi-JunB transgenic mice. Our findings identify ATF3 as a novel downstream target of JunB in the survival mechanism of β-cells under inflammatory stress....

The ATF [Advanced Toroidal Facility] Status and Control System

International Nuclear Information System (INIS)

Baylor, L.R.; Devan, W.R.; Sumner, J.N.; Alban, A.M.

1987-01-01

The Advanced Toroidal Facility (ATF) Status and Control System (SCS) is a programmable controller-based state monitoring and supervisory control system. This paper describes the SCS implementation and its use of a host computer to run a commercially available software package that provides color graphic interactive displays, alarm logging, and archiving of state data

Experimental results of the ATF in-line injection system

International Nuclear Information System (INIS)

Wang, X.J.; Srinivasan-Rao, T.; Batchelor, K.

1995-01-01

The initial experimental results of the Brookhaven accelerator test facility (ATF) in-line injector is presented. The ATF in-line injector employed a full copper RF gun with a pair of solenoid magnets for emittance compensation. The maximum acceleration field of the RF gun was measured to be 130 MV/m. The electron yield from the copper cathode was maximized using p- polarized laser and the Schottky effect. The quantum efficiency under optimum conditions was measured to be 0.04%. The measured electron bunch length was less than 11 ps, which agreed with the laser pulse length measurement using a streak camera. The normalized rms. emittance for 0.25 nC charge is 0.9 ± 0.1 mm-mrad, which is almost four times smaller than the emittance predicted by the space-charge effect for a non-emittance compensation photocathode RF gun. The normalized rms for 0.6 nC charge was measured range from 1 to 3 mm-mrad. This measurement was first experimental demonstration of emittance compensation in a high-gradient, S-band photocathode RF gun

Frank-ter Haar syndrome protein Tks4 regulates epidermal growth factor-dependent cell migration.

Science.gov (United States)

Bögel, Gábor; Gujdár, Annamária; Geiszt, Miklós; Lányi, Árpád; Fekete, Anna; Sipeki, Szabolcs; Downward, Julian; Buday, László

2012-09-07

Mutations in the SH3PXD2B gene coding for the Tks4 protein are responsible for the autosomal recessive Frank-ter Haar syndrome. Tks4, a substrate of Src tyrosine kinase, is implicated in the regulation of podosome formation. Here, we report a novel role for Tks4 in the EGF signaling pathway. In EGF-treated cells, Tks4 is tyrosine-phosphorylated and associated with the activated EGF receptor. This association is not direct but requires the presence of Src tyrosine kinase. In addition, treatment of cells with LY294002, an inhibitor of PI 3-kinase, or mutations of the PX domain reduces tyrosine phosphorylation and membrane translocation of Tks4. Furthermore, a PX domain mutant (R43W) Tks4 carrying a reported point mutation in a Frank-ter Haar syndrome patient showed aberrant intracellular expression and reduced phosphoinositide binding. Finally, silencing of Tks4 was shown to markedly inhibit HeLa cell migration in a Boyden chamber assay in response to EGF or serum. Our results therefore reveal a new function for Tks4 in the regulation of growth factor-dependent cell migration.

Carbon monoxide protects against hepatic steatosis in mice by inducing sestrin-2 via the PERK-eIF2α-ATF4 pathway.

Science.gov (United States)

Kim, Hyo Jeong; Joe, Yeonsoo; Kim, Seul-Ki; Park, Se-Ung; Park, Jeongmin; Chen, Yingqing; Kim, Jin; Ryu, Jinhyun; Cho, Gyeong Jae; Surh, Young-Joon; Ryter, Stefan W; Kim, Uh-Hyun; Chung, Hun-Taeg

2017-09-01

Nonalcoholic fatty liver disease (NAFLD), the hepatic manifestation of the metabolic syndrome, has emerged as one of the most common causes of chronic liver disease in developed countries over the last decade. NAFLD comprises a spectrum of pathological hepatic changes, including steatosis, steatohepatitis, advanced fibrosis, and cirrhosis. Autophagy, a homeostatic process for protein and organelle turnover, is decreased in the liver during the development of NAFLD. Previously, we have shown that carbon monoxide (CO), a reaction product of heme oxygenase (HO) activity, can confer protection in NAFLD, though the molecular mechanisms remain unclear. We therefore investigated the mechanisms underlying the protective effect of CO on methionine/choline-deficient (MCD) diet-induced hepatic steatosis. We found that CO induced sestrin-2 (SESN2) expression through enhanced mitochondrial ROS production and protected against MCD-induced NAFLD progression through activation of autophagy. SESN2 expression was increased by CO or CO-releasing molecule (CORM2), in a manner dependent on signaling through the protein kinase R-like endoplasmic reticulum kinase (PERK), eukaryotic initiation factor-2 alpha (eIF2α)/ activating transcription factor-4 (ATF4)-dependent pathway. CO-induced SESN2 upregulation in hepatocytes contributed to autophagy induction through activation of 5'-AMP-activated protein kinase (AMPK) and inhibition of mechanistic target of rapamycin (mTOR) complex I (mTORC1). Furthermore, we demonstrate that CO significantly induced the expression of SESN2 and enhanced autophagy in the livers of MCD-fed mice or in MCD-media treated hepatocytes. Conversely, knockdown of SESN2 abrogated autophagy activation and mTOR inhibition in response to CO. We conclude that CO ameliorates hepatic steatosis through the autophagy pathway induced by SESN2 upregulation. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Role of TLR4/NADPH oxidase/ROS-activated p38 MAPK in VCAM-1 expression induced by lipopolysaccharide in human renal mesangial cells

Directory of Open Access Journals (Sweden)

Lee I-Ta

2012-11-01

Full Text Available Abstract Background In bacteria-induced glomerulonephritis, Toll-like receptor 4 (TLR4 activation by lipopolysaccharide (LPS, a key component of the outer membranes of Gram-negative bacteria can increase oxidative stress and the expression of vascular cell adhesion molecule-1 (VCAM-1, which recruits leukocytes to the glomerular mesangium. However, the mechanisms underlying VCAM-1 expression induced by LPS are still unclear in human renal mesangial cells (HRMCs. Results We demonstrated that LPS induced VCAM-1 mRNA and protein levels associated with an increase in the promoter activity of VCAM-1, determined by Western blot, RT-PCR, and promoter assay. LPS-induced responses were inhibited by transfection with siRNAs of TLR4, myeloid differentiation factor 88 (MyD88, Nox2, Nox4, p47phox, c-Src, p38 MAPK, activating transcription factor 2 (ATF2, and p300 or pretreatment with the inhibitors of reactive oxygen species (ROS, edaravone, NADPH oxidase [apocynin (APO or diphenyleneiodonium chloride (DPI], c-Src (PP1, p38 MAPK (SB202190, and p300 (GR343. LPS induced NADPH oxidase activation, ROS production, and p47phox translocation from the cytosol to the membrane, which were reduced by PP1 or c-Src siRNA. We observed that LPS induced TLR4, MyD88, c-Src, and p47phox complex formation determined by co-immunoprecipitation and Western blot. We further demonstrated that LPS stimulated ATF2 and p300 phosphorylation and complex formation via a c-Src/NADPH oxidase/ROS/p38 MAPK pathway. Up-regulation of VCAM-1 led to enhancing monocyte adhesion to HRMCs challenged with LPS, which was inhibited by siRNAs of c-Src, p47phox, p38 MAPK, ATF2, and p300 or pretreatment with an anti-VCAM-1 neutralizing antibody. Conclusions In HRMCs, LPS-induced VCAM-1 expression was, at least in part, mediated through a TLR4/MyD88/ c-Src/NADPH oxidase/ROS/p38 MAPK-dependent p300 and ATF2 pathway associated with recruitment of monocyte adhesion to kidney. Blockade of these pathways may

G-actin sequestering protein thymosin-β4 regulates the activity of myocardin-related transcription factor

International Nuclear Information System (INIS)

Morita, Tsuyoshi; Hayashi, Ken’ichiro

2013-01-01

Highlights: •Tβ4 competed with MRTF-A for G-actin binding. •Tβ4 activated the MRTF–SRF signaling pathway. •Tβ4 increased the endogenous expression of SRF-dependent genes. -- Abstract: Myocardin-related transcription factors (MRTFs) are robust coactivators of serum response factor (SRF). MRTFs contain three copies of the RPEL motif at their N-terminus, and they bind to monomeric globular actin (G-actin). Previous studies illustrate that G-actin binding inhibits MRTF activity by preventing the MRTFs nuclear accumulation. In the living cells, the majority of G-actin is sequestered by G-actin binding proteins that prevent spontaneous actin polymerization. Here, we demonstrate that the most abundant G-actin sequestering protein thymosin-β4 (Tβ4) was involved in the regulation of subcellular localization and activity of MRTF-A. Tβ4 competed with MRTF-A for G-actin binding; thus, interfering with G-actin–MRTF-A complex formation. Tβ4 overexpression induced the MRTF-A nuclear accumulation and activation of MRTF–SRF signaling. The activation rate of MRTF-A by the Tβ4 mutant L17A, whose affinity for G-actin is very low, was lower than that by wild-type Tβ4. In contrast, the β-actin mutant 3DA, which has a lower affinity for Tβ4, more effectively suppressed MRTF-A activity than wild-type β-actin. Furthermore, ectopic Tβ4 increased the endogenous expression of SRF-dependent actin cytoskeletal genes. Thus, Tβ4 is an important MRTF regulator that controls the G-actin–MRTFs interaction

G-actin sequestering protein thymosin-β4 regulates the activity of myocardin-related transcription factor

Energy Technology Data Exchange (ETDEWEB)

Morita, Tsuyoshi, E-mail: tsuyo@nbiochem.med.osaka-u.ac.jp; Hayashi, Ken’ichiro

2013-08-02

Highlights: •Tβ4 competed with MRTF-A for G-actin binding. •Tβ4 activated the MRTF–SRF signaling pathway. •Tβ4 increased the endogenous expression of SRF-dependent genes. -- Abstract: Myocardin-related transcription factors (MRTFs) are robust coactivators of serum response factor (SRF). MRTFs contain three copies of the RPEL motif at their N-terminus, and they bind to monomeric globular actin (G-actin). Previous studies illustrate that G-actin binding inhibits MRTF activity by preventing the MRTFs nuclear accumulation. In the living cells, the majority of G-actin is sequestered by G-actin binding proteins that prevent spontaneous actin polymerization. Here, we demonstrate that the most abundant G-actin sequestering protein thymosin-β4 (Tβ4) was involved in the regulation of subcellular localization and activity of MRTF-A. Tβ4 competed with MRTF-A for G-actin binding; thus, interfering with G-actin–MRTF-A complex formation. Tβ4 overexpression induced the MRTF-A nuclear accumulation and activation of MRTF–SRF signaling. The activation rate of MRTF-A by the Tβ4 mutant L17A, whose affinity for G-actin is very low, was lower than that by wild-type Tβ4. In contrast, the β-actin mutant 3DA, which has a lower affinity for Tβ4, more effectively suppressed MRTF-A activity than wild-type β-actin. Furthermore, ectopic Tβ4 increased the endogenous expression of SRF-dependent actin cytoskeletal genes. Thus, Tβ4 is an important MRTF regulator that controls the G-actin–MRTFs interaction.

Design of bunch compressing system with suppression of coherent synchrotron radiation for ATF upgrade

International Nuclear Information System (INIS)

Jing, Yichao; Fedurin, Mikhail; Stratakis, Diktys

2015-01-01

One of the operation modes for Accelerator Test Facility (ATF) upgrade is to provide high peak current, high quality electron beam for users. Such operation requires a bunch compressing system with a very large compression ratio. The CSR originating from the strong compressors generally could greatly degrade the quality of the electron beam. In this paper, we present our design for the entire bunch compressing system that will limit the effect of CSR on the e-beam@s quality. We discuss and detail the performance from the start to end simulation of such a compressor for ATF.

Isoform-specific regulation of osteogenic factors by polypeptide N-Acetylgalactosaminyltransferases 1 and 4

International Nuclear Information System (INIS)

Tang, Juan; Zheng, Hanxi; Chen, Ling; Gao, Shangshang; Shi, Xiaorui; Liu, Jingjing; Xu, Lan

2017-01-01

The family of UDP-GalNAc polypeptide: N-Acetylgalactosaminlytransfersases (ppGalNAcTs) catalyzes the initial step of O-linked protein glycosylation. Mucin-type O-glycoproteins are abundant in the bone and may play an important role in osteogenesis. Herein, we examined the effects of ppGalNAc-T isoforms on osteogenesis of MC3T3-E1 pre-osteoblasts. We found that ppGalNAc-T1 and -T4 isoforms were highly expressed during osteogenesis of MC3T3-E1 and their knockdown by short hairpin RNA (shRNA) decreased osteoblast formation and bone mineralization. Knockdown of ppGalNAc-T1 or -T4 decreased mRNA and protein levels of bone sialoprotein (BSP). Knockdown of ppGalNAc-T1decreased mRNA levels of osteocalcin (OC), osteoprotegerin (OPG). Knockdown ofppGalNAc-T4 isoform decreased mRNA levels of OC, OPG and vitamin D receptor (VDR). While knockdown of T1 or T4 isoforms did not change the expression of osteopontin (OPN), COLLI, receptor activator for nuclear factor-κB ligand (RANKL) and transforming growth factor-β (TGF-β). Our results demonstrated that the ppGalNAc-T4 was highly expressed in MC3T3-E1 cells during osteogenesis for the first time. We also found that ppGalNAc-T1 and -T4 affected the expression of different osteogenic factors, suggesting distinct roles ppGalNAc-T isoformsplay in regulating osteogenesis in vitro. - Highlights: • ppGalNAc-T1 and T4 are highly expressed during MC3T3 cell osteogenesis. • Knockdown of ppGalNAc-T1 and -T4 decreases osteogenic differentiation and mineralization. • Expression of osteogenic factors are differentially affected by decreased ppGalNAc-T1 and -T4 expression.

Fuel licensing process for an industrial use. ATF licensing process for an industrial use - Utility's perspective

International Nuclear Information System (INIS)

Waeckel, Nicolas

2013-01-01

To develop and license a breakthrough nuclear fuel technology for commercial use is becoming challenging. All the former safety analysis design limits (SAFDLs) defined in the 1970's for the standard UO 2 -Zr fuels, might no longer be applicable. Identification of the appropriate safety analysis design limits For each type of innovative fuel, the developers will have to identify and investigate all the possible failure/ruins scenarios (not only those related to severe accidents but also those related to normal operation). In order to save time and to focus on the best options, those failure scenarios (which could be 'killers' for the ATF concept) have to be determined early enough in the development process. Based on the above failure scenarios, the developers will have to propose the licensing limits (and the experimental protocol to determine and to justify them). As mentioned earlier, the licensing limits should not be defined against the accidental conditions only. For the operators, the (good) in-reactor fuel behaviour is crucial. As an example, in the case of the new fuel concepts coming with an outer coating, it is important to include the analysis of the consequences of the loss of this protective outer layer in the licensing process due to a manufacturing defect or an inevitable in-reactor fretting wear. Obviously, the new/specific SAFDLs will have to be endorsed by the regulators (which could be a long process by itself). Identification of a commercial reactor to irradiate the first ATF A commercial NPP is not a material test reactor (MTR); irradiating lead test fuel rods (LTFRs) or lead test assemblies (LTAs) implies strict requirements regarding the manufacturing processes [which should not include chemicals (additives or solvents) potentially incompatible with the nuclear technical specifications], the compatibility with the hosting fuel core (in terms of geometry, enrichment, thermal hydraulic performances, etc.) and the robustness and

Opportunities for the LWR ATF materials development program to contribute to the LBE-cooled ADS materials qualification program

Energy Technology Data Exchange (ETDEWEB)

Gong, Xing, E-mail: gongxingzfl@hotmail.com [Department of ATF R& D, Nuclear Fuel Research and Development Center, China Nuclear Power Technology Research Institute Co., Ltd., China General Nuclear Power Corporation (CGN), Shenzhen, 518026 (China); Li, Rui, E-mail: li-rui@cgnpc.com.cn [Department of ATF R& D, Nuclear Fuel Research and Development Center, China Nuclear Power Technology Research Institute Co., Ltd., China General Nuclear Power Corporation (CGN), Shenzhen, 518026 (China); Sun, Maozhou; Ren, Qisen [Department of ATF R& D, Nuclear Fuel Research and Development Center, China Nuclear Power Technology Research Institute Co., Ltd., China General Nuclear Power Corporation (CGN), Shenzhen, 518026 (China); Liu, Tong, E-mail: liutong@cgnpc.com.cn [Department of ATF R& D, Nuclear Fuel Research and Development Center, China Nuclear Power Technology Research Institute Co., Ltd., China General Nuclear Power Corporation (CGN), Shenzhen, 518026 (China); Short, Michael P., E-mail: hereiam@mit.edu [Department of Nuclear Science and Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA, 02139 (United States)

2016-12-15

Accelerator-driven systems (ADS) are a promising approach for nuclear waste disposal. Nevertheless, the principal candidate materials proposed for ADS construction, such as the ferritic/martensitic steel, T91, and austenitic stainless steels, 316L and 15-15Ti, are not fully compatible with the liquid lead-bismuth eutectic (LBE) coolant. Under some operating conditions, liquid metal embrittlement (LME) or liquid metal corrosion (LMC) may occur in these steels when exposed to LBE. These environmentally-induced material degradation effects pose a threat to ADS reactor safety, as failure of the materials could initiate a severe accident, in which fission products are released into the coolant. Meanwhile, parallel efforts to develop accident-tolerant fuels (ATF) in light water reactors (LWRs) could provide both general materials design philosophies and specific material solutions to the ADS program. In this paper, the potential contributions of the ATF materials development program to the ADS materials qualification program are evaluated and discussed in terms of service conditions and materials performance requirements. Several specific areas where coordinated development may benefit both programs, including composite materials and selected coatings, are discussed. - Highlights: • ATF materials developed for LWRs could be candidate materials for the LBE-cooled ADS program. • Similar material design and protection philosophies are utilized in both programs. • Unique challenges of LBE-cooled ADS systems could possibly be addressed by LWR ATF materials. • More coordinated testing should be performed between the ATF and ADS programs.

Hypoxic induction of the regulator of G-protein signalling 4 gene is mediated by the hypoxia-inducible factor pathway.

Directory of Open Access Journals (Sweden)

Sam W Z Olechnowicz

Full Text Available The transcriptional response to hypoxia is largely dependent on the Hypoxia Inducible Factors (HIF-1 and HIF-2 in mammalian cells. Many target genes have been characterised for these heterodimeric transcription factors, yet there is evidence that the full range of HIF-regulated genes has not yet been described. We constructed a TetON overexpression system in the rat pheochromocytoma PC-12 cell line to search for novel HIF and hypoxia responsive genes. The Rgs4 gene encodes the Regulator of G-Protein Signalling 4 (RGS4 protein, an inhibitor of signalling from G-protein coupled receptors, and dysregulation of Rgs4 is linked to disease states such as schizophrenia and cardiomyopathy. Rgs4 was found to be responsive to HIF-2α overexpression, hypoxic treatment, and hypoxia mimetic drugs in PC-12 cells. Similar responses were observed in human neuroblastoma cell lines SK-N-SH and SK-N-BE(2C, but not in endothelial cells, where Rgs4 transcript is readily detected but does not respond to hypoxia. Furthermore, this regulation was found to be dependent on transcription, and occurs in a manner consistent with direct HIF transactivation of Rgs4 transcription. However, no HIF binding site was detectable within 32 kb of the human Rgs4 gene locus, leading to the possibility of regulation by long-distance genomic interactions. Further research into Rgs4 regulation by hypoxia and HIF may result in better understanding of disease states such as schizophrenia, and also shed light on the other roles of HIF yet to be discovered.

Hypoxic Induction of the Regulator of G-Protein Signalling 4 Gene Is Mediated by the Hypoxia-Inducible Factor Pathway

Science.gov (United States)

Olechnowicz, Sam W. Z.; Fedele, Anthony O.; Peet, Daniel J.

2012-01-01

The transcriptional response to hypoxia is largely dependent on the Hypoxia Inducible Factors (HIF-1 and HIF-2) in mammalian cells. Many target genes have been characterised for these heterodimeric transcription factors, yet there is evidence that the full range of HIF-regulated genes has not yet been described. We constructed a TetON overexpression system in the rat pheochromocytoma PC-12 cell line to search for novel HIF and hypoxia responsive genes. The Rgs4 gene encodes the Regulator of G-Protein Signalling 4 (RGS4) protein, an inhibitor of signalling from G-protein coupled receptors, and dysregulation of Rgs4 is linked to disease states such as schizophrenia and cardiomyopathy. Rgs4 was found to be responsive to HIF-2α overexpression, hypoxic treatment, and hypoxia mimetic drugs in PC-12 cells. Similar responses were observed in human neuroblastoma cell lines SK-N-SH and SK-N-BE(2)C, but not in endothelial cells, where Rgs4 transcript is readily detected but does not respond to hypoxia. Furthermore, this regulation was found to be dependent on transcription, and occurs in a manner consistent with direct HIF transactivation of Rgs4 transcription. However, no HIF binding site was detectable within 32 kb of the human Rgs4 gene locus, leading to the possibility of regulation by long-distance genomic interactions. Further research into Rgs4 regulation by hypoxia and HIF may result in better understanding of disease states such as schizophrenia, and also shed light on the other roles of HIF yet to be discovered. PMID:22970249

Studies of emittance growth in the ATF

International Nuclear Information System (INIS)

Zimmermann, F.

1997-03-01

Several different mechanisms of emittance growth in the Accelerator Test Facility (ATF) at KEK are investigated: the author calculates rise times of the fast beam-ion instability for the damping ring (DR), and discusses the emittance growth caused by coherent synchrotron radiation in the beam-transport line (BT), the effect of quadrupole wake fields in the injector linac, and, finally, a single-bunch head-tail ion effect that can occur in both the DR and the BT. A first attempt to measure the quadrupole wake on the real machine is also reported

Nuclear factor 1 regulates adipose tissue-specific expression in the mouse GLUT4 gene

International Nuclear Information System (INIS)

Miura, Shinji; Tsunoda, Nobuyo; Ikeda, Shinobu; Kai, Yuko; Cooke, David W.; Lane, M. Daniel; Ezaki, Osamu

2004-01-01

Previous studies demonstrated that an adipose tissue-specific element(s) (ASE) of the murine GLUT4 gene is located between -551 and -506 in the 5'-flanking sequence and that a high-fat responsive element(s) for down-regulation of the GLUT4 gene is located between bases -701 and -552. A binding site for nuclear factor 1 (NF1), that mediates insulin and cAMP-induced repression of GLUT4 in 3T3-L1 adipocytes is located between bases -700 and -688. To examine the role of NF1 in the regulation of GLUT4 gene expression in white adipose tissues (WAT) in vivo, we created two types of transgenic mice harboring mutated either 5' or 3' half-site of NF1-binding sites in GLUT4 minigene constructs. In both cases, the GLUT4 minigene was not expressed in WAT, while expression was maintained in brown adipose tissue, skeletal muscle, and heart. This was an unexpected finding, since a -551 GLUT4 minigene that did not have the NF1-binding site was expressed in WAT. We propose a model that explains the requirement for both the ASE and the NF1-binding site for expression of GLUT4 in WAT

COX-2 gene expression in colon cancer tissue related to regulating factors and promoter methylation status

International Nuclear Information System (INIS)

Asting, Annika Gustafsson; Carén, Helena; Andersson, Marianne; Lönnroth, Christina; Lagerstedt, Kristina; Lundholm, Kent

2011-01-01

Increased cyclooxygenase activity promotes progression of colorectal cancer, but the mechanisms behind COX-2 induction remain elusive. This study was therefore aimed to define external cell signaling and transcription factors relating to high COX-2 expression in colon cancer tissue. Tumor and normal colon tissue were collected at primary curative operation in 48 unselected patients. COX-2 expression in tumor and normal colon tissue was quantified including microarray analyses on tumor mRNA accounting for high and low tumor COX-2 expression. Cross hybridization was performed between tumor and normal colon tissue. Methylation status of up-stream COX-2 promoter region was evaluated. Tumors with high COX-2 expression displayed large differences in gene expression compared to normal colon. Numerous genes with altered expression appeared in tumors of high COX-2 expression compared to tumors of low COX-2. COX-2 expression in normal colon was increased in patients with tumors of high COX-2 compared to normal colon from patients with tumors of low COX-2. IL1β, IL6 and iNOS transcripts were up-regulated among external cell signaling factors; nine transcription factors (ATF3, C/EBP, c-Fos, Fos-B, JDP2, JunB, c-Maf, NF-κB, TCF4) showed increased expression and 5 (AP-2, CBP, Elk-1, p53, PEA3) were decreased in tumors with high COX-2. The promoter region of COX-2 gene did not show consistent methylation in tumor or normal colon tissue. Transcription and external cell signaling factors are altered as covariates to COX-2 expression in colon cancer tissue, but DNA methylation of the COX-2 promoter region was not a significant factor behind COX-2 expression in tumor and normal colon tissue

COX-2 gene expression in colon cancer tissue related to regulating factors and promoter methylation status

Directory of Open Access Journals (Sweden)

Lagerstedt Kristina

2011-06-01

Full Text Available Abstract Background Increased cyclooxygenase activity promotes progression of colorectal cancer, but the mechanisms behind COX-2 induction remain elusive. This study was therefore aimed to define external cell signaling and transcription factors relating to high COX-2 expression in colon cancer tissue. Method Tumor and normal colon tissue were collected at primary curative operation in 48 unselected patients. COX-2 expression in tumor and normal colon tissue was quantified including microarray analyses on tumor mRNA accounting for high and low tumor COX-2 expression. Cross hybridization was performed between tumor and normal colon tissue. Methylation status of up-stream COX-2 promoter region was evaluated. Results Tumors with high COX-2 expression displayed large differences in gene expression compared to normal colon. Numerous genes with altered expression appeared in tumors of high COX-2 expression compared to tumors of low COX-2. COX-2 expression in normal colon was increased in patients with tumors of high COX-2 compared to normal colon from patients with tumors of low COX-2. IL1β, IL6 and iNOS transcripts were up-regulated among external cell signaling factors; nine transcription factors (ATF3, C/EBP, c-Fos, Fos-B, JDP2, JunB, c-Maf, NF-κB, TCF4 showed increased expression and 5 (AP-2, CBP, Elk-1, p53, PEA3 were decreased in tumors with high COX-2. The promoter region of COX-2 gene did not show consistent methylation in tumor or normal colon tissue. Conclusions Transcription and external cell signaling factors are altered as covariates to COX-2 expression in colon cancer tissue, but DNA methylation of the COX-2 promoter region was not a significant factor behind COX-2 expression in tumor and normal colon tissue.

Latest Performance Results from the FONT5 Intra-train Beam Position and Angle Feedback System at ATF2

CERN Document Server

Christian, G B; Bett, D R; Blaskovic Kraljevic, N; Burrows, P N; Davis, M R; Gerbershagen, A; Perry, C; Constance, B; Resta-Lopez, J

2012-01-01

A prototype Interaction Point beam-based feedback system for future electron-positron colliders, such as the International Linear Collider, has been designed and tested on the extraction line of the KEK Accelerator Test Facility (ATF). The FONT5 intra-train feedback system aims to stabilize the beam orbit by correcting both the position and angle jitter in the vertical plane on bunch-tobunch time scales, providing micron-level stability at the entrance to the ATF2 final-focus system. The system comprises three stripline beam position monitors (BPMs) and two stripline kickers, custom low-latency analogue front-end BPM processors, a custom FPGA-based digital processing board with fast ADCs, and custom kickerdrive amplifiers. The latest results from beam tests at ATF2 will be presented, including the system latency and correction performance.

FIR interferometer and scattering measurements of ATF

International Nuclear Information System (INIS)

Ma, C.H.; Hutchinson, D.P.; Fockedey, Y.; Vander Sluis, K.L.; Bennett, C.A.

1989-01-01

A 15-channel far-infrared (FIR) interferometer system has been constructed to measure the electron densities on the ATF plasmas. The system consists of a pair of cw 214-μm difluoromethane (CH 2 F 2 ) lasers, optically pumped by separate CO 2 lasers. The large number of channels is achieved by the use of reflective beam expansion optics to create a beam of 2 cm /times/ 45 cm. After passing through the plasma discharge, the elongated beam produced by the cylindrical mirrors is dissected by an array of 15 off-axis paraboloid reflectors, each of which illuminates a single Schottky-diode detector. The use of the beam expanding optics system reduces the number of optical elements required for the interferometer to approximately 2-3 per channel. The FIR laser beams are transported from the laser room to the experimental area by 25 mm i.d. dielectric waveguides purged with dry nitrogen. The system can also be operated at a wavelength of 119-μm by changing the gas in FIR laser cavities to methanol for high density experiments. Details of the system are described. A study is underway to determine the optimum design of a FIR scattering system for the ATF. This scattering system will be used to investigate density fluctuations with scale lengths from 0.1 cm to the plasma radius. The laser for this scattering system may be operated at wavelengths of 447, 307, 214, 184, and 119 μm with power levels of 100 to 500 mW. A summary of the study is presented. 6 refs., 1 fig

The Brookhaven ATF low-emittance beam line

International Nuclear Information System (INIS)

Wang, X.J.; Kirk, H.G.

1991-01-01

One component of the experimental program at the Brookhaven Accelerator Test Facility (ATF) consists of a class of experiments which will study the acceleration of electrons through micron-size structures which are exposed in coincidence to a 100 GW CO 2 laser beam. These experiments require the development and control of an electron beam with geometric emittances on the order of 10 -10 m-rad and intensities on the order of 10 6 electrons. In this paper, the authors describe the strategies for producing such beams and the effects of higher-order aberrations. Particle tracking results are presented for the final-focus system

Fast wave heating experiments in the ion cyclotron range of frequencies on ATF

Energy Technology Data Exchange (ETDEWEB)

Kwon, M; Shepard, T D; Goulding, R H [Oak Ridge National Lab., TN (United States); and others

1992-07-01

Fast wave heating experiments in the ion cyclotron range of frequencies (ICRF) were performed on target plasmas produced by 350 kW of electron cyclotron heating at 53 GHz and also by neutral beam injection in the Advanced Toroidal Facility (ATF). Various heating regimes were investigated in the frequency range between 9.2 MHz and 28.8 MHz with magnetic fields of 0.95 T and 1.9 T on axis. The nominal pulse lengths of up to 200 kW RF power were in the range between 100 and 400 ms. Data from spectroscopy, loading measurements, and edge RF and Langmuir probes were used to characterize the RF induced effects on the ATF plasma. In the hydrogen minority regime at low plasma density, large suprathermal ion tails were observed with a neutral particle analyser. At high density (n-bar{sub e} {>=} 5.0 x 10{sup 13} cm{sup -3}) substantial increases in antenna loading were observed, but ICRF power was insufficient to produce definitive heating results. A two-dimensional RF heating code, ORION, and a Fokker-Planck code, RFTRANS, were used to simulate these experiments. A simulation of future high power, higher density experiments in ATF indicates improved bulk heating results due to the improved loading and more efficient thermalization of the minority tail. (author). 29 refs, 16 figs, 3 tabs.

The ATF two-frequency correlation reflectometer

International Nuclear Information System (INIS)

Hanson, G.R.; Wilgen, J.B.; Anabitarte, E.; Bell, J.D.; Harris, J.H.; Dunlap, J.L.; Thomas, C.E.

1990-01-01

The Advanced Toroidal Facility (ATF) density fluctuation reflectometer system consists of two individual reflectometers operating in the 30- to 40-GHz band. Each reflectometer consists of a tunable microwave source and a quadrature phase detector connected to the same antenna system. This arrangement allows two-frequency operation along the same radial chord for radial coherence measurements. The technique used in making radial coherence measurements is discussed and the results of such experiments are given. Initial experiments have shown high coherence when the frequencies of the two reflectometers are tuned close together and a clear loss of coherence as the radial separation of the cutoff layers is increased by increasing the frequency separation of the two reflectometers. Recent results have shown that local measurements of density fluctuations in plasmas with electron cyclotron heating (ECH) are possible and that detailed structure can be seen in the fluctuation spectra. In addition, radial correlation lengths have been found to be from 0.5 to 1.0 cm in ECH plasmas, with some frequency structures having correlation lengths up to 3 cm. In plasmas with neutral beam injection (NBI), the radial correlation lengths in the edge region have been found to be approximately 0.1--0.2 cm. 4 figs

The transcription factor ABI4 Is required for the ascorbic acid-dependent regulation of growth and regulation of jasmonate-dependent defense signaling pathways in Arabidopsis.

Science.gov (United States)

Kerchev, Pavel I; Pellny, Till K; Vivancos, Pedro Diaz; Kiddle, Guy; Hedden, Peter; Driscoll, Simon; Vanacker, Hélène; Verrier, Paul; Hancock, Robert D; Foyer, Christine H

2011-09-01

Cellular redox homeostasis is a hub for signal integration. Interactions between redox metabolism and the ABSCISIC ACID-INSENSITIVE-4 (ABI4) transcription factor were characterized in the Arabidopsis thaliana vitamin c defective1 (vtc1) and vtc2 mutants, which are defective in ascorbic acid synthesis and show a slow growth phenotype together with enhanced abscisic acid (ABA) levels relative to the wild type (Columbia-0). The 75% decrease in the leaf ascorbate pool in the vtc2 mutants was not sufficient to adversely affect GA metabolism. The transcriptome signatures of the abi4, vtc1, and vtc2 mutants showed significant overlap, with a large number of transcription factors or signaling components similarly repressed or induced. Moreover, lincomycin-dependent changes in LIGHT HARVESTING CHLOROPHYLL A/B BINDING PROTEIN 1.1 expression were comparable in these mutants, suggesting overlapping participation in chloroplast to nucleus signaling. The slow growth phenotype of vtc2 was absent in the abi4 vtc2 double mutant, as was the sugar-insensitive phenotype of the abi4 mutant. Octadecanoid derivative-responsive AP2/ERF-domain transcription factor 47 (ORA47) and AP3 (an ABI5 binding factor) transcripts were enhanced in vtc2 but repressed in abi4 vtc2, suggesting that ABI4 and ascorbate modulate growth and defense gene expression through jasmonate signaling. We conclude that low ascorbate triggers ABA- and jasmonate-dependent signaling pathways that together regulate growth through ABI4. Moreover, cellular redox homeostasis exerts a strong influence on sugar-dependent growth regulation.

Specificity versus redundancy in the RAP2.4 transcription factor family of Arabidopsis thaliana: transcriptional regulation of genes for chloroplast peroxidases.

Science.gov (United States)

Rudnik, Radoslaw; Bulcha, Jote Tafese; Reifschneider, Elena; Ellersiek, Ulrike; Baier, Margarete

2017-08-23

The Arabidopsis ERFIb / RAP2.4 transcription factor family consists of eight members with highly conserved DNA binding domains. Selected members have been characterized individually, but a systematic comparison is pending. The redox-sensitive transcription factor RAP2.4a mediates chloroplast-to-nucleus redox signaling and controls induction of the three most prominent chloroplast peroxidases, namely 2-Cys peroxiredoxin A (2CPA) and thylakoid- and stromal ascorbate peroxidase (tAPx and sAPx). To test the specificity and redundancy of RAP2.4 transcription factors in the regulation of genes for chloroplast peroxidases, we compared the DNA-binding sites of the transcription factors in tertiary structure models, analyzed transcription factor and target gene regulation by qRT-PCR in RAP2.4, 2-Cys peroxiredoxin and ascorbate peroxidase T-DNA insertion lines and RAP2.4 overexpressing lines of Arabidopsis thaliana and performed promoter binding studies. All RAP2.4 proteins bound the tAPx promoter, but only the four RAP2.4 proteins with identical DNA contact sites, namely RAP2.4a, RAP2.4b, RAP2.4d and RAP2.4h, interacted stably with the redox-sensitive part of the 2CPA promoter. Gene expression analysis in RAP2.4 knockout lines revealed that RAP2.4a is the only one supporting 2CPA and chloroplast APx expression. Rap2.4h binds to the same promoter region as Rap2.4a and antagonizes 2CPA expression. Like the other six RAP2.4 proteins, Rap2.4 h promotes APx mRNA accumulation. Chloroplast ROS signals induced RAP2.4b and RAP2.4d expression, but these two transcription factor genes are (in contrast to RAP2.4a) insensitive to low 2CP availability, and their expression decreased in APx knockout lines. RAP2.4e and RAP2.4f gradually responded to chloroplast APx availability and activated specifically APx expression. These transcription factors bound, like RAP2.4c and RAP2.4g, the tAPx promoter, but hardly the 2CPA promoter. The RAP2.4 transcription factors form an environmentally and

Phytochrome-interacting factors PIF4 and PIF5 negatively regulate anthocyanin biosynthesis under red light in Arabidopsis seedlings.

Science.gov (United States)

Liu, Zhongjuan; Zhang, Yongqiang; Wang, Jianfeng; Li, Ping; Zhao, Chengzhou; Chen, Yadi; Bi, Yurong

2015-09-01

Light is an important environmental factor inducing anthocyanin accumulation in plants. Phytochrome-interacting factors (PIFs) have been shown to be a family of bHLH transcription factors involved in light signaling in Arabidopsis. Red light effectively increased anthocyanin accumulation in wild-type Col-0, whereas the effects were enhanced in pif4 and pif5 mutants but impaired in overexpression lines PIF4OX and PIF5OX, indicating that PIF4 and PIF5 are both negative regulators for red light-induced anthocyanin accumulation. Consistently, transcript levels of several genes involved in anthocyanin biosynthesis and regulatory pathway, including CHS, F3'H, DFR, LDOX, PAP1 and TT8, were significantly enhanced in mutants pif4 and pif5 but decreased in PIF4OX and PIF5OX compared to in Col-0, indicating that PIF4 and PIF5 are transcriptional repressor of these gene. Transient expression assays revealed that PIF4 and PIF5 could repress red light-induced promoter activities of F3'H and DFR in Arabidopsis protoplasts. Furthermore, chromatin immunoprecipitation-quantitative PCR (ChIP-qPCR) test and electrophoretic mobility shift assay (EMSA) showed that PIF5 could directly bind to G-box motifs present in the promoter of DFR. Taken together, these results suggest that PIF4 and PIF5 negatively regulate red light-induced anthocyanin accumulation through transcriptional repression of the anthocyanin biosynthetic genes in Arabidopsis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

The Brookhaven ATF low-emittance beam line

International Nuclear Information System (INIS)

Wang, X.J.

1991-01-01

One component of the experimental program at the Brookhaven Accelerator Test Facility (ATF) consists of a class of experiments which will study the acceleration of electrons through micron-size structures which are exposed in coincidence to a 100 GW CO 2 laser beam. These experiments require the development and control of an electron beam with geometric emittances on the order of 10 -10 m-rad and intensities on the order of 10 6 electrons. In this paper, we describe the strategies for producing such beams and the effects of high-order aberrations. Particle tracking results are presented for the final-focus system. 9 refs., 6 figs., 2 tabs

The transcription factor FOXO4 is down-regulated and inhibits tumor proliferation and metastasis in gastric cancer

International Nuclear Information System (INIS)

Su, Linna; Liu, Xiangqiang; Chai, Na; Lv, Lifen; Wang, Rui; Li, Xiaosa; Nie, Yongzhan; Shi, Yongquan; Fan, Daiming

2014-01-01

FOXO4, a member of the FOXO family of transcription factors, is currently the focus of intense study. Its role and function in gastric cancer have not been fully elucidated. The present study was aimed to investigate the expression profile of FOXO4 in gastric cancer and the effect of FOXO4 on cancer cell growth and metastasis. Immunohistochemistry, Western blotting and qRT-PCR were performed to detect the FOXO4 expression in gastric cancer cells and tissues. Cell biological assays, subcutaneous tumorigenicity and tail vein metastatic assay in combination with lentivirus construction were performed to detect the impact of FOXO4 to gastric cancer in proliferation and metastasis in vitro and in vivo. Confocal and qRT-PCR were performed to explore the mechanisms. We found that the expression of FOXO4 was decreased significantly in most gastric cancer tissues and in various human gastric cancer cell lines. Up-regulating FOXO4 inhibited the growth and metastasis of gastric cancer cell lines in vitro and led to dramatic attenuation of tumor growth, and liver and lung metastasis in vivo, whereas down-regulating FOXO4 with specific siRNAs promoted the growth and metastasis of gastric cancer cell lines. Furthermore, we found that up-regulating FOXO4 could induce significant G1 arrest and S phase reduction and down-regulation of the expression of vimentin. Our data suggest that loss of FOXO4 expression contributes to gastric cancer growth and metastasis, and it may serve as a potential therapeutic target for gastric cancer

Hypoxic stress up-regulates the expression of Toll-like receptor 4 in macrophages via hypoxia-inducible factor.

Science.gov (United States)

Kim, So Young; Choi, Yong Jun; Joung, Sun Myung; Lee, Byung Ho; Jung, Yi-Sook; Lee, Joo Young

2010-04-01

Toll-like receptors (TLRs) are germline-encoded innate immune receptors that recognize invading micro-organisms and induce immune and inflammatory responses. Deregulation of TLRs is known to be closely linked to various immune disorders and inflammatory diseases. Cells at sites of inflammation are exposed to hypoxic stress, which further aggravates inflammatory processes. We have examined if hypoxic stress modulates the TLR activity of macrophages. Hypoxia and CoCl(2) (a hypoxia mimetic) enhanced the expression of TLR4 messenger RNA and protein in macrophages (RAW264.7 cells), whereas the messenger RNA of other TLRs was not increased. To determine the underlying mechanism, we investigated the role of hypoxia-inducible factor 1 (HIF-1) in the regulation of TLR4 expression. Knockdown of HIF-1alpha expression by small interfering RNA inhibited hypoxia-induced and CoCl(2)-induced TLR4 expression in macrophages, while over-expression of HIF-1alpha potentiated TLR4 expression. Chromatin immunoprecipitation assays revealed that HIF-1alpha binds to the TLR4 promoter region under hypoxic conditions. In addition, deletion or mutation of a putative HIF-1-binding motif in the TLR4 promoter greatly attenuated HIF-1alpha-induced TLR4 promoter reporter expression. Up-regulation of TLR4 expression by hypoxic stress enhanced the response of macrophages to lipopolysaccharide, resulting in increased expression of cyclooxygenase-2, interleukin-6, regulated on activation normal T cell expressed and secreted, and interferon-inducible protein-10. These results demonstrate that TLR4 expression in macrophages is up-regulated via HIF-1 in response to hypoxic stress, suggesting that hypoxic stress at sites of inflammation enhances susceptibility to subsequent infection and inflammatory signals by up-regulating TLR4.

Identification of the G13 (cAMP-response-element-binding protein-related protein) gene product related to activating transcription factor 6 as a transcriptional activator of the mammalian unfolded protein response.

Science.gov (United States)

Haze, K; Okada, T; Yoshida, H; Yanagi, H; Yura, T; Negishi, M; Mori, K

2001-04-01

Eukaryotic cells control the levels of molecular chaperones and folding enzymes in the endoplasmic reticulum (ER) by a transcriptional induction process termed the unfolded protein response (UPR). The mammalian UPR is mediated by the cis-acting ER stress response element consisting of 19 nt (CCAATN(9)CCACG), the CCACG part of which is considered to provide specificity. We recently identified the basic leucine zipper (bZIP) protein ATF6 as a mammalian UPR-specific transcription factor; ATF6 is activated by ER stress-induced proteolysis and binds directly to CCACG. Here we report that eukaryotic cells express another bZIP protein closely related to ATF6 in both structure and function. This protein encoded by the G13 (cAMP response element binding protein-related protein) gene is constitutively synthesized as a type II transmembrane glycoprotein anchored in the ER membrane and processed into a soluble form upon ER stress as occurs with ATF6. The proteolytic processing of ATF6 and the G13 gene product is accompanied by their relocation from the ER to the nucleus; their basic regions seem to function as a nuclear localization signal. Overexpression of the soluble form of the G13 product constitutively activates the UPR, whereas overexpression of a mutant lacking the activation domain exhibits a strong dominant-negative effect. Furthermore, the soluble forms of ATF6 and the G13 gene product are unable to bind to several point mutants of the cis-acting ER stress response element in vitro that hardly respond to ER stress in vivo. We thus concluded that the two related bZIP proteins are crucial transcriptional regulators of the mammalian UPR, and propose calling the ATF6 gene product ATF6alpha and the G13 gene product ATF6beta.

Regulation of IFN regulatory factor 4 expression in human T cell leukemia virus-I-transformed T cells.

Science.gov (United States)

Sharma, Sonia; Grandvaux, Nathalie; Mamane, Yael; Genin, Pierre; Azimi, Nazli; Waldmann, Thomas; Hiscott, John

2002-09-15

IFN regulatory factor (IRF)-4 is a lymphoid/myeloid-restricted member of the IRF transcription factor family that plays an essential role in the homeostasis and function of mature lymphocytes. IRF-4 expression is tightly regulated in resting primary T cells and is transiently induced at the mRNA and protein levels after activation by Ag-mimetic stimuli such as TCR cross-linking or treatment with phorbol ester and calcium ionophore (PMA/ionomycin). However, IRF-4 is constitutively upregulated in human T cell leukemia virus type I (HTLV-I) infected T cells as a direct gene target for the HTLV-I Tax oncoprotein. In this study we demonstrate that chronic IRF-4 expression in HTLV-I-infected T lymphocytes is associated with a leukemic phenotype, and we examine the mechanisms by which continuous production of IRF-4 is achieved in HTLV-I-transformed T cells. IRF-4 expression in HTLV-1-infected cells is driven through activation of the NF-kappaB and NF-AT pathways, resulting in the binding of p50, p65, and c-Rel to the kappaB1 element and p50, c-Rel, and NF-ATp to the CD28RE element within the -617 to -209 region of the IRF-4 promoter. Furthermore, mutation of either the kappaB1 or CD28RE sites blocks Tax-mediated transactivation of the human IRF-4 promoter in T cells. These experiments constitute the first detailed analysis of human IRF-4 transcriptional regulation within the context of HTLV-I infection and transformation of CD4(+) T lymphocytes.

Edge turbulence and transport: Text and ATF modeling

International Nuclear Information System (INIS)

Ritz, C.P.; Rhodes, T.L.; Lin, H.; Rowan, W.L.; Bengtson, R.; Wootton, A.J.; Diamond, P.H.; Ware, A.S.; Thayer, D.R.

1990-01-01

We present experimental results on edge turbulence and transport from the tokamak TEXT and the torsatron ATF. The measured electrostatic fluctuations can explain the edge transport of particles and energy. Certain drive (radiation) and stabilizing (velocity shear) terms are suggested by the results. The experimental fluctuation levels and spectral widths can be reproduced by considering the nonlinear evolution of the reduced MHD equations, incorporating a thermal drive from line radiation. In the tokamak limit (with toroidal electric field) the model corresponds to the resistivity gradient mode, while in the currentless torsatron or stellarator limit it corresponds to a thermally driven drift wave

Turn by Turn Measurements at the KEK-ATF

CERN Document Server

Renier, Y; Tomas, R; Wendt, M; Eddy, N; Kubo, K; Kuroda, S; Naito, T; Okugi, T; Terunuma, N; Urakawa, J

2013-01-01

The ATF damping ring has been upgraded with new read-out electronics for the beam position monitors (BPM), capable to acquire the beam orbits on a turn-by-turn basis, as well as in a high resolution averaging mode. The new BPM system allows to improve optic corrections and to achieve an even smaller vertical emittance (<2pm). Experimental results are presented based on turn-by-turn beam orbit measurements in the ring, for estimating the β functions and dispersion along the lattice. A fast method to measure spectral line amplitude in a few turns is also presented, including the evaluation of chromaticity.

Chromatin-Bound MDM2 Regulates Serine Metabolism and Redox Homeostasis Independently of p53.

Science.gov (United States)

Riscal, Romain; Schrepfer, Emilie; Arena, Giuseppe; Cissé, Madi Y; Bellvert, Floriant; Heuillet, Maud; Rambow, Florian; Bonneil, Eric; Sabourdy, Frédérique; Vincent, Charles; Ait-Arsa, Imade; Levade, Thierry; Thibaut, Pierre; Marine, Jean-Christophe; Portais, Jean-Charles; Sarry, Jean-Emmanuel; Le Cam, Laurent; Linares, Laetitia K

2016-06-16

The mouse double minute 2 (MDM2) oncoprotein is recognized as a major negative regulator of the p53 tumor suppressor, but growing evidence indicates that its oncogenic activities extend beyond p53. Here, we show that MDM2 is recruited to chromatin independently of p53 to regulate a transcriptional program implicated in amino acid metabolism and redox homeostasis. Identification of MDM2 target genes at the whole-genome level highlights an important role for ATF3/4 transcription factors in tethering MDM2 to chromatin. MDM2 recruitment to chromatin is a tightly regulated process that occurs during oxidative stress and serine/glycine deprivation and is modulated by the pyruvate kinase M2 (PKM2) metabolic enzyme. Depletion of endogenous MDM2 in p53-deficient cells impairs serine/glycine metabolism, the NAD(+)/NADH ratio, and glutathione (GSH) recycling, impacting their redox state and tumorigenic potential. Collectively, our data illustrate a previously unsuspected function of chromatin-bound MDM2 in cancer cell metabolism. Copyright © 2016 Elsevier Inc. All rights reserved.

Meis1 regulates Foxn4 expression during retinal progenitor cell differentiation

Directory of Open Access Journals (Sweden)

Mohammed M. Islam

2013-09-01

The transcription factor forkhead box N4 (Foxn4 is a key regulator in a variety of biological processes during development. In particular, Foxn4 plays an essential role in the genesis of horizontal and amacrine neurons from neural progenitors in the vertebrate retina. Although the functions of Foxn4 have been well established, the transcriptional regulation of Foxn4 expression during progenitor cell differentiation remains unclear. Here, we report that an evolutionarily conserved 129 bp noncoding DNA fragment (Foxn4CR4.2 or CR4.2, located ∼26 kb upstream of Foxn4 transcription start site, functions as a cis-element for Foxn4 regulation. CR4.2 directs gene expression in Foxn4-positive cells, primarily in progenitors, differentiating horizontal and amacrine cells. We further determined that the gene regulatory activity of CR4.2 is modulated by Meis1 binding motif, which is bound and activated by Meis1 transcription factor. Deletion of the Meis1 binding motif or knockdown of Meis1 expression abolishes the gene regulatory activity of CR4.2. In addition, knockdown of Meis1 expression diminishes the endogenous Foxn4 expression and affects cell lineage development. Together, we demonstrate that CR4.2 and its interacting Meis1 transcription factor play important roles in regulating Foxn4 expression during early retinogenesis. These findings provide new insights into molecular mechanisms that govern gene regulation in retinal progenitors and specific cell lineage development.

Activating transcription factor 3 is a target molecule linking hepatic steatosis to impaired glucose homeostasis.

Science.gov (United States)

Kim, Ji Yeon; Park, Keon Jae; Hwang, Joo-Yeon; Kim, Gyu Hee; Lee, DaeYeon; Lee, Yoo Jeong; Song, Eun Hyun; Yoo, Min-Gyu; Kim, Bong-Jo; Suh, Young Ho; Roh, Gu Seob; Gao, Bin; Kim, Won; Kim, Won-Ho

2017-08-01

Non-alcoholic fatty liver disease (NAFLD) contributes to impaired glucose tolerance, leading to type 2 diabetes (T2D); however, the precise mechanisms and target molecules that are involved remain unclear. Activating transcription factor 3 (ATF3) is associated with β-cell dysfunction that is induced by severe stress signals in T2D. We aimed to explore the exact functional role of ATF3 as a mechanistic link between hepatic steatosis and T2D development. Zucker diabetic fatty (ZDF) rats were utilized for animal experiments. An in vivo-jetPEI siRNA delivery system against ATF3 was used for loss-of-function experiments. We analyzed the baseline cross-sectional data derived from the biopsy-proven NAFLD registry (n=322). Human sera and liver tissues were obtained from 43 patients with biopsy-proven NAFLD and from seven healthy participants. ATF3 was highly expressed in the livers of ZDF rats and in human participants with NAFLD and/or T2D. Insulin resistance and hepatic steatosis were associated with increased ATF3 expression and decreased fatty acid oxidation via mitochondrial dysfunction and were attenuated by in vivo ATF3 silencing. Knockdown of ATF3 also ameliorated glucose intolerance, impaired insulin action, and inflammatory responses in ZDF rats. In patients with NAFLD and/or T2D, a significant positive correlation was observed between hepatic ATF3 expression and surrogate markers of T2D, mitochondrial dysfunction, and macrophage infiltration. Increased hepatic ATF3 expression is closely associated with hepatic steatosis and incident T2D; therefore, ATF3 may serve as a potential therapeutic target for NAFLD and hepatic steatosis-induced T2D. Hepatic activating transcription factor 3 (ATF3) may play an important role in oxidative stress-mediated hepatic steatosis and the development of type 2 diabetes (T2D) in a Zucker diabetic fatty (ZDF) rat model and in human patients with non-alcoholic fatty liver disease (NAFLD). Therefore, ATF3 may be a useful biomarker for

Identification of a c-Jun N-terminal kinase-2-dependent signal amplification cascade that regulates c-Myc levels in ras transformation

DEFF Research Database (Denmark)

Mathiasen, D.P.; Egebjerg, C.; Andersen, S.H.

2012-01-01

are essential for ras transformation. Previous studies show that ERK-mediated serine 62 phosphorylation protects c-Myc from proteasomal degradation. ERK is, however, not alone sufficient to stabilize c-Myc but requires the cooperation of cancerous inhibitor of protein phosphatase 2A (CIP2A), an oncogene...... that counteracts protein phosphatase 2A-mediated dephosphorylation of c-Myc. Here we show that JNK2 regulates Cip2a transcription via ATF2. ATF2 and c-Myc cooperate to activate the transcription of ATF3. Remarkably, not only ectopic JNK2, but also ectopic ATF2, CIP2A, c-Myc and ATF3 are sufficient to rescue...... the defective ras transformation of JNK2-deficient cells. Thus, these data identify the key signal converging point of JNK2 and ERK pathways and underline the central role of CIP2A in ras transformation.Oncogene advance online publication, 27 June 2011; doi:10.1038/onc.2011.230....

The Transcription Factor ABI4 Is Required for the Ascorbic Acid–Dependent Regulation of Growth and Regulation of Jasmonate-Dependent Defense Signaling Pathways in Arabidopsis[C][W

Science.gov (United States)

Kerchev, Pavel I.; Pellny, Till K.; Vivancos, Pedro Diaz; Kiddle, Guy; Hedden, Peter; Driscoll, Simon; Vanacker, Hélène; Verrier, Paul; Hancock, Robert D.; Foyer, Christine H.

2011-01-01

Cellular redox homeostasis is a hub for signal integration. Interactions between redox metabolism and the ABSCISIC ACID-INSENSITIVE-4 (ABI4) transcription factor were characterized in the Arabidopsis thaliana vitamin c defective1 (vtc1) and vtc2 mutants, which are defective in ascorbic acid synthesis and show a slow growth phenotype together with enhanced abscisic acid (ABA) levels relative to the wild type (Columbia-0). The 75% decrease in the leaf ascorbate pool in the vtc2 mutants was not sufficient to adversely affect GA metabolism. The transcriptome signatures of the abi4, vtc1, and vtc2 mutants showed significant overlap, with a large number of transcription factors or signaling components similarly repressed or induced. Moreover, lincomycin-dependent changes in LIGHT HARVESTING CHLOROPHYLL A/B BINDING PROTEIN 1.1 expression were comparable in these mutants, suggesting overlapping participation in chloroplast to nucleus signaling. The slow growth phenotype of vtc2 was absent in the abi4 vtc2 double mutant, as was the sugar-insensitive phenotype of the abi4 mutant. Octadecanoid derivative-responsive AP2/ERF-domain transcription factor 47 (ORA47) and AP3 (an ABI5 binding factor) transcripts were enhanced in vtc2 but repressed in abi4 vtc2, suggesting that ABI4 and ascorbate modulate growth and defense gene expression through jasmonate signaling. We conclude that low ascorbate triggers ABA- and jasmonate-dependent signaling pathways that together regulate growth through ABI4. Moreover, cellular redox homeostasis exerts a strong influence on sugar-dependent growth regulation. PMID:21926335

The first terawatt picosecond CO2 laser for advanced accelerator studies at the Brookhaven ATF

International Nuclear Information System (INIS)

Pogorelsky, I.V.; Ben-Zvi, I.; Skaritka, J.

1996-10-01

The first terawatt picosecond C0 2 laser system is under development at the Brookhaven Accelerator Test Facility. Presently operational 1 Joule 100-ps ATF laser will be upgraded with a 10 atm amplifier capable of delivery ∼ 15 Joules of laser energy in a 3 ps pulse. We describe the design of the x-ray preionized 10 atm amplifier of a 10 liter active volume energized by a 1 MV, 200 kA transverse electric discharge. The amplifier, equipped with internal optics, permits the accommodation of a regenerative stage and a multi-pass booster in a relatively compact single discharge volume. The ATF terawatt C0 2 laser shall become operational in 1997 to serve for laser acceleration, x-ray generation and other strong-field physics experiments

Connective tissue fibroblasts and Tcf4 regulate myogenesis

Science.gov (United States)

Mathew, Sam J.; Hansen, Jody M.; Merrell, Allyson J.; Murphy, Malea M.; Lawson, Jennifer A.; Hutcheson, David A.; Hansen, Mark S.; Angus-Hill, Melinda; Kardon, Gabrielle

2011-01-01

Muscle and its connective tissue are intimately linked in the embryo and in the adult, suggesting that interactions between these tissues are crucial for their development. However, the study of muscle connective tissue has been hindered by the lack of molecular markers and genetic reagents to label connective tissue fibroblasts. Here, we show that the transcription factor Tcf4 (transcription factor 7-like 2; Tcf7l2) is strongly expressed in connective tissue fibroblasts and that Tcf4GFPCre mice allow genetic manipulation of these fibroblasts. Using this new reagent, we find that connective tissue fibroblasts critically regulate two aspects of myogenesis: muscle fiber type development and maturation. Fibroblasts promote (via Tcf4-dependent signals) slow myogenesis by stimulating the expression of slow myosin heavy chain. Also, fibroblasts promote the switch from fetal to adult muscle by repressing (via Tcf4-dependent signals) the expression of developmental embryonic myosin and promoting (via a Tcf4-independent mechanism) the formation of large multinucleate myofibers. In addition, our analysis of Tcf4 function unexpectedly reveals a novel mechanism of intrinsic regulation of muscle fiber type development. Unlike other intrinsic regulators of fiber type, low levels of Tcf4 in myogenic cells promote both slow and fast myogenesis, thereby promoting overall maturation of muscle fiber type. Thus, we have identified novel extrinsic and intrinsic mechanisms regulating myogenesis. Most significantly, our data demonstrate for the first time that connective tissue is important not only for adult muscle structure and function, but is a vital component of the niche within which muscle progenitors reside and is a critical regulator of myogenesis. PMID:21177349

Small molecule proteostasis regulators that reprogram the ER to reduce extracellular protein aggregation

Science.gov (United States)

Plate, Lars; Cooley, Christina B; Chen, John J; Paxman, Ryan J; Gallagher, Ciara M; Madoux, Franck; Genereux, Joseph C; Dobbs, Wesley; Garza, Dan; Spicer, Timothy P; Scampavia, Louis; Brown, Steven J; Rosen, Hugh; Powers, Evan T; Walter, Peter; Hodder, Peter; Wiseman, R Luke; Kelly, Jeffery W

2016-01-01

Imbalances in endoplasmic reticulum (ER) proteostasis are associated with etiologically-diverse degenerative diseases linked to excessive extracellular protein misfolding and aggregation. Reprogramming of the ER proteostasis environment through genetic activation of the Unfolded Protein Response (UPR)-associated transcription factor ATF6 attenuates secretion and extracellular aggregation of amyloidogenic proteins. Here, we employed a screening approach that included complementary arm-specific UPR reporters and medium-throughput transcriptional profiling to identify non-toxic small molecules that phenocopy the ATF6-mediated reprogramming of the ER proteostasis environment. The ER reprogramming afforded by our molecules requires activation of endogenous ATF6 and occurs independent of global ER stress. Furthermore, our molecules phenocopy the ability of genetic ATF6 activation to selectively reduce secretion and extracellular aggregation of amyloidogenic proteins. These results show that small molecule-dependent ER reprogramming, achieved through preferential activation of the ATF6 transcriptional program, is a promising strategy to ameliorate imbalances in ER function associated with degenerative protein aggregation diseases. DOI: http://dx.doi.org/10.7554/eLife.15550.001 PMID:27435961

Development of the alternate entry port for the ATF

International Nuclear Information System (INIS)

Parsa, Z.

1993-05-01

We discussed a second entry port for the Accelerator Test Facility (ATF) injection system at Brookhaven National Laboratory, which consists of a photocathode rf gun and a straight - ahead beamline directly into the 50 MeV linac. The proposed second entry port should improve the beam quality and lower the emittance needed for FEL (Free Electron Laser), and laser - acceleration experiments. A discussion on the laser driven high brightness photoelectrons through the primary entry port (a low energy 180 degrees achromatic double bend transport line) now in operation, and a beam analysis for the proposed secondary port is also given

ETS-4 is a transcriptional regulator of life span in Caenorhabditis elegans.

Directory of Open Access Journals (Sweden)

Bargavi Thyagarajan

2010-09-01

Full Text Available Aging is a complex phenotype responsive to a plethora of environmental inputs; yet only a limited number of transcriptional regulators are known to influence life span. How the downstream expression programs mediated by these factors (or others are coordinated into common or distinct set of aging effectors is an addressable question in model organisms, such as C. elegans. Here, we establish the transcription factor ETS-4, an ortholog of vertebrate SPDEF, as a longevity determinant. Adult worms with ets-4 mutations had a significant extension of mean life span. Restoring ETS-4 activity in the intestine, but not neurons, of ets-4 mutant worms rescued life span to wild-type levels. Using RNAi, we demonstrated that ets-4 is required post-developmentally to regulate adult life span; thus uncoupling the role of ETS-4 in aging from potential functions in worm intestinal development. Seventy ETS-4-regulated genes, identified by gene expression profiling of two distinct ets-4 alleles and analyzed by bioinformatics, were enriched for known longevity effectors that function in lipid transport, lipid metabolism, and innate immunity. Putative target genes were enriched for ones that change expression during normal aging, the majority of which are controlled by the GATA factors. Also, some ETS-4-regulated genes function downstream of the FOXO factor, DAF-16 and the insulin/IGF-1 signaling pathway. However, epistasis and phenotypic analyses indicate that ets-4 functioned in parallel to the insulin/IGF-1 receptor, daf-2 and akt-1/2 kinases. Furthermore, ets-4 required daf-16 to modulate aging, suggesting overlap in function at the level of common targets that affect life span. In conclusion, ETS-4 is a new transcriptional regulator of aging, which shares transcriptional targets with GATA and FOXO factors, suggesting that overlapping pathways direct common sets of lifespan-related genes.

Timing system for multi-bunch/multi-train operation at ATF

International Nuclear Information System (INIS)

Naito, T.; Hayano, H.; Urakawa, J.; Imai, T.

2000-01-01

A timing system has been constructed for multi-bunch/multi-train operation at KEK-ATF. The linac accelerates 20 bunches of multi-bunch with 2.8 ns spacing. The Damping Ring stores up to 5 trains of multi-bunch. The timing system is required to provide flexible operation mode and bucket selection. A personal computer is used for manipulating the timing. The performance of kicker magnets at the injection/extruction is key issue for multi-train operation. The hardware and the test results are presented. (author)

Heavy ion beam probe diagnostic system for ATF

International Nuclear Information System (INIS)

Carnevali, A.; Misium, J.; Lewis, J.F.; Connor, K.A.

1986-01-01

The potential structure in non-axisymmetric toroidal confinement devices is largely responsible for the particle drift surfaces. A heavy ion beam probe diagnostic, which can directly determine the potential, is thus planned for ATF. The most significant device characteristics affecting the implementation of such a system on this complex magnetic geometry that were not encountered on tokamaks are the large toroidal separation (15 degrees) of vertical and horizontal ports and substantial magnetic return fields in the region of the ion optics and energy analyzer electric fields. The status of the design is presented with particular emphasis on the choice of energy analyzer required by the large dispersion in ion trajectories produced by this field

Yes-associated protein/TEA domain family member and hepatocyte nuclear factor 4-alpha (HNF4α) repress reciprocally to regulate hepatocarcinogenesis in rats and mice.

Science.gov (United States)

Cai, Wang-Yu; Lin, Ling-Yun; Hao, Han; Zhang, Sai-Man; Ma, Fei; Hong, Xin-Xin; Zhang, Hui; Liu, Qing-Feng; Ye, Guo-Dong; Sun, Guang-Bin; Liu, Yun-Jia; Li, Sheng-Nan; Xie, Yuan-Yuan; Cai, Jian-Chun; Li, Bo-An

2017-04-01

Great progress has been achieved in the study of Hippo signaling in regulating tumorigenesis; however, the downstream molecular events that mediate this process have not been completely defined. Moreover, regulation of Hippo signaling during tumorigenesis in hepatocellular carcinoma (HCC) remains largely unknown. In the present study, we systematically investigated the relationship between Yes-associated protein/TEA domain family member (YAP-TEAD) and hepatocyte nuclear factor 4-alpha (HNF4α) in the hepatocarcinogenesis of HCC cells. Our results indicated that HNF4α expression was negatively regulated by YAP1 in HCC cells by a ubiquitin proteasome pathway. By contrast, HNF4α was found to directly associate with TEAD4 to compete with YAP1 for binding to TEAD4, thus inhibiting the transcriptional activity of YAP-TEAD and expression of their target genes. Moreover, overexpression of HNF4α was found to significantly compromise YAP-TEAD-induced HCC cell proliferation and stem cell expansion. Finally, we documented the regulatory mechanism between YAP-TEAD and HNF4α in rat and mouse tumor models, which confirmed our in vitro results. There is a double-negative feedback mechanism that controls TEAD-YAP and HNF4α expression in vitro and in vivo, thereby regulating cellular proliferation and differentiation. Given that YAP acts as a dominant oncogene in HCC and plays a crucial role in stem cell homeostasis and tissue regeneration, manipulating the interaction between YAP, TEADs, and HNF4α may provide a new approach for HCC treatment and regenerative medicine. (Hepatology 2017;65:1206-1221). © 2016 by the American Association for the Study of Liver Diseases.

A TAD further: exogenous control of gene activation.

Science.gov (United States)

Mapp, Anna K; Ansari, Aseem Z

2007-01-23

Designer molecules that can be used to impose exogenous control on gene transcription, artificial transcription factors (ATFs), are highly desirable as mechanistic probes of gene regulation, as potential therapeutic agents, and as components of cell-based devices. Recently, several advances have been made in the design of ATFs that activate gene transcription (activator ATFs), including reports of small-molecule-based systems and ATFs that exhibit potent activity. However, the many open mechanistic questions about transcriptional activators, in particular, the structure and function of the transcriptional activation domain (TAD), have hindered rapid development of synthetic ATFs. A compelling need thus exists for chemical tools and insights toward a more detailed portrait of the dynamic process of gene activation.

High resolution upgrade of the ATF damping ring BPM system

International Nuclear Information System (INIS)

Terunuma, N.; Urakawa, J.; Frisch, J.; May, J.; McCormick, D.; Nelson, J.; Seryi, A.; Smith, T.; Woodley, M.; Briegel, C.; Dysert, R.

2008-01-01

A beam position monitor (BPM) upgrade at the KEK Accelerator Test Facility (ATF) damping ring has been accomplished in its first stage, carried out by a KEK/FNAL/SLAC collaboration under the umbrella of the global ILC R and D effort. The upgrade consists of a high resolution, high reproducibility read-out system, based on analog and digital downconversion techniques, digital signal processing, and also tests a new automatic gain error correction schema. The technical concept and realization, as well as preliminary results of beam studies are presented

Zeff measurements in ATF using visible bremsstrahlung

International Nuclear Information System (INIS)

Morita, S.; Richards, R.K.; Horton, L.D.; Isler, R.C.; Crume, E.C. Jr.; Murakami, M.

1991-04-01

Measurements of the effective charge Z eff in plasmas with electron cyclotron heating (ECH) and neutral beam injection (NBI) in the Advanced Toroidal Facility (ATF) have been carried out using visible bremsstrahlung. The electron temperature needed for the analysis is calculated from the measured stored energy and electron density. The value of Z eff varies widely depending on experimental conditions. In ECH plasmas it is between 2 and 8. In NBI plasmas, which are subject to radiation collapse, Z eff is between 3 and 5 at the time the stored energy reaches a maximum. However, Z eff is less than 2.5 in quasi-steady medium-density plasmas and is close to 1.2 in the highest-density plasmas, where the average electron density bar n e is of the order of 10 14 cm -3 . 12 refs., 29 figs., 1 tab

Two CGTCA motifs and a GHF1/Pit1 binding site mediate cAMP-dependent protein kinase A regulation of human growth hormone gene expression in rat anterior pituitary GC cells.

Science.gov (United States)

Shepard, A R; Zhang, W; Eberhardt, N L

1994-01-21

We established the cis-acting elements which mediate cAMP responsiveness of the human growth hormone (hGH) gene in transiently transfected rat anterior pituitary tumor GC cells. Analysis of the intact hGH gene or hGH 5'-flanking DNA (5'-FR) coupled to the hGh cDNA or chloramphenicol acetyltransferase or luciferase genes, indicated that cAMP primarily stimulated hGH promoter activity. Cotransfection of a protein kinase A inhibitory protein cDNA demonstrated that the cAMP response was mediated by protein kinase A. Mutational analysis of the hGH promoter identified two core cAMP response element motifs (CGTCA) located at nucleotides -187/-183 (distal cAMP response element; dCRE) and -99/-95 (proximal cAMP response element; pCRE) and a pituitary-specific transcription factor (GHF1/Pit1) binding site at nucleotides -123/-112 (dGHF1) which were required for cAMP responsiveness. GHF1 was not a limiting factor, since overexpression of GHF1 in cotransfections increased basal but not forskolin induction levels. Gel shift analyses indicated that similar, ubiquitous, thermostable protein(s) specifically bound the pCRE and dCRE motifs. The CGTCA motif-binding factors were cAMP response element binding protein (CREB)/activating transcription factor-1 (ATF-1)-related, since the DNA-protein complex was competed by unlabeled CREB consensus oligonucleotide, specifically supershifted by antisera to CREB and ATF-1 but not ATF-2, and was bound by purified CREB with the same relative binding affinity (pCRE < dCRE < CREB) and mobility as the GC nuclear extract. UV cross-linking and Southwestern blot analyses revealed multiple DNA-protein interactions of which approximately 100- and approximately 45-kDa proteins were predominant; the approximately 45-kDa protein may represent CREB. These results indicate that CREB/ATF-1-related factors act coordinately with the cell-specific factor GHF1 to mediate cAMP-dependent regulation of hGH-1 gene transcription in anterior pituitary somatotrophs.

A Project to Design and Build the Magnets for a New Test Beamline, the ATF2, at KEK

Energy Technology Data Exchange (ETDEWEB)

Spencer, Cherrill M.; /slac; Sugahara, Ryuhei; Masuzawa, Mika; /KEK, Tsukuba; Bolzon, Benoit; Jeremie, Andrea; /Annecy, LAPP

2011-02-07

In order to achieve the high luminosity required at the proposed International Linear Collider (ILC), it is critical to focus the beams to nanometer size with the ILC Beam Delivery System, and to maintain the beams collisions with a nanometer-scale stability. To establish the technologies associated with this ultra-high precision beam handling, a special beamline has been designed and built as an extension of the existing extraction beamline of the Accelerator Test Facility at KEK, Japan. The ATF provides an adequate ultra-low emittance electron beam that is comparable to the ILC requirements; the ATF2 mimics the ILC final focus system to create a tightly focused, stable beam. There are 37 magnets in the ATF2, 29 quadrupoles, 5 sextupoles and 3 bends. These magnets had to be acquired in a short time and at minimum cost, which led to various acquisition strategies; but nevertheless they had to meet strict requirements on integrated strength, physical dimensions, compatibility with existing magnet movers and beam position monitors, mechanical stability and field stability and quality. This paper will describe how 2 styles of quadrupoles, 2 styles of sextupoles, one dipole style and their supports were designed, fabricated, refurbished or modified, measured and aligned by a small team of engineers from 3 continents.

The ethylene response factor AtERF4 negatively regulates the iron deficiency response in Arabidopsis thaliana.

Directory of Open Access Journals (Sweden)

Wei Liu

Full Text Available Iron (Fe deficiency is one of many conditions that can seriously damage crops. Low levels of photosynthesis can lead to the degradation of chlorophyll content and impaired respiration in affected plants, which together cause poor growth and reduce quality. Although ethylene plays an important role in responses to Fe deficiency, a limited number of studies have been carried out on ethylene response factor (ERFs as components of plant regulation mechanisms. Thus, this study aimed to investigate the role of AtERF4 in plant responses to Fe deficiency. Results collected when Arabidopsis thaliana was grown under Fe deficient conditions as well as in the presence of 1-aminocyclopropane-1-carboxylic acid (ACC revealed that leaf chlorosis did not occur over short timescales and that chloroplast structural integrity was retained. At the same time, expression of the chlorophyll degradation-related genes AtPAO and AtCLH1 was inhibited and net H+ root flux was amplified. Our results show that chlorophyll content was enhanced in the mutant erf4, while expression of the chlorophyll degradation gene AtCLH1 was reduced. Ferric reductase activity in roots was also significantly higher in the mutant than in wild type plants, while erf4 caused high levels of expression of the genes AtIRT1 and AtHA2 under Fe deficient conditions. We also utilized yeast one-hybrid technology in this study to determine that AtERF4 binds directly to the AtCLH1 and AtITR1 promoter. Observations show that transient over-expression of AtERF4 resulted in rapid chlorophyll degradation in the leaves of Nicotiana tabacum and the up-regulation of gene AtCLH1 expression. In summary, AtERF4 plays an important role as a negative regulator of Fe deficiency responses, we hypothesize that AtERF4 may exert a balancing effect on plants subject to nutrition stress.

ZFHX4 interacts with the NuRD core member CHD4 and regulates the glioblastoma tumor-initiating cell state.

Science.gov (United States)

Chudnovsky, Yakov; Kim, Dohoon; Zheng, Siyuan; Whyte, Warren A; Bansal, Mukesh; Bray, Mark-Anthony; Gopal, Shuba; Theisen, Matthew A; Bilodeau, Steve; Thiru, Prathapan; Muffat, Julien; Yilmaz, Omer H; Mitalipova, Maya; Woolard, Kevin; Lee, Jeongwu; Nishimura, Riko; Sakata, Nobuo; Fine, Howard A; Carpenter, Anne E; Silver, Serena J; Verhaak, Roel G W; Califano, Andrea; Young, Richard A; Ligon, Keith L; Mellinghoff, Ingo K; Root, David E; Sabatini, David M; Hahn, William C; Chheda, Milan G

2014-01-30

Glioblastoma (GBM) harbors subpopulations of therapy-resistant tumor-initiating cells (TICs) that are self-renewing and multipotent. To understand the regulation of the TIC state, we performed an image-based screen for genes regulating GBM TIC maintenance and identified ZFHX4, a 397 kDa transcription factor. ZFHX4 is required to maintain TIC-associated and normal human neural precursor cell phenotypes in vitro, suggesting that ZFHX4 regulates differentiation, and its suppression increases glioma-free survival in intracranial xenografts. ZFHX4 interacts with CHD4, a core member of the nucleosome remodeling and deacetylase (NuRD) complex. ZFHX4 and CHD4 bind to overlapping sets of genomic loci and control similar gene expression programs. Using expression data derived from GBM patients, we found that ZFHX4 significantly affects CHD4-mediated gene expression perturbations, which defines ZFHX4 as a master regulator of CHD4. These observations define ZFHX4 as a regulatory factor that links the chromatin-remodeling NuRD complex and the GBM TIC state. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

ZFHX4 interacts with the NuRD core member CHD4 and regulates the glioblastoma tumor initiating cell state

Science.gov (United States)

Chudnovsky, Yakov; Kim, Dohoon; Zheng, Siyuan; Whyte, Warren A.; Bansal, Mukesh; Bray, Mark-Anthony; Gopal, Shuba; Theisen, Matthew A.; Bilodeau, Steve; Thiru, Prathapan; Muffat, Julien; Yilmaz, Omer H.; Mitalipova, Maya; Woolard, Kevin; Lee, Jeongwu; Nishimura, Riko; Sakata, Nobuo; Fine, Howard A.; Carpenter, Anne E.; Silver, Serena J.; Verhaak, Roel G. W.; Califano, Andrea; Young, Richard A.; Ligon, Keith L.; Mellinghoff, Ingo K.; Root, David E.; Sabatini, David M.; Hahn, William C.; Chheda, Milan G.

2014-01-01

Summary Glioblastomas (GBM) harbor subpopulations of therapy-resistant tumor initiating cells (TICs) that are self-renewing and multipotent. To understand the regulation of the TIC state, we performed an image-based screen for genes regulating GBM TIC maintenance and identified ZFHX4, a 397-kDa transcription factor. ZFHX4 is required to maintain TIC-associated and normal human neural precursor cell phenotypes in vitro, suggesting that ZFHX4 regulates differentiation, and its suppression increases glioma-free survival in intracranial xenografts. ZFHX4 interacts with CHD4, a core member of the NuRD (nucleosome remodeling and deacetylase) complex. ZFHX4 and CHD4 bind to overlapping sets of genomic loci and control similar gene expression programs. Using expression data derived from GBM patients, we found that ZFHX4 significantly affects CHD4-mediated gene expression perturbations, which defines ZFHX4 as a master regulator of CHD4. These observations define ZFHX4 as a regulatory factor that links the chromatin remodeling NuRD complex and the GBM TIC state. PMID:24440720

ZFHX4 Interacts with the NuRD Core Member CHD4 and Regulates the Glioblastoma Tumor-Initiating Cell State

Directory of Open Access Journals (Sweden)

Yakov Chudnovsky

2014-01-01

Full Text Available Glioblastoma (GBM harbors subpopulations of therapy-resistant tumor-initiating cells (TICs that are self-renewing and multipotent. To understand the regulation of the TIC state, we performed an image-based screen for genes regulating GBM TIC maintenance and identified ZFHX4, a 397 kDa transcription factor. ZFHX4 is required to maintain TIC-associated and normal human neural precursor cell phenotypes in vitro, suggesting that ZFHX4 regulates differentiation, and its suppression increases glioma-free survival in intracranial xenografts. ZFHX4 interacts with CHD4, a core member of the nucleosome remodeling and deacetylase (NuRD complex. ZFHX4 and CHD4 bind to overlapping sets of genomic loci and control similar gene expression programs. Using expression data derived from GBM patients, we found that ZFHX4 significantly affects CHD4-mediated gene expression perturbations, which defines ZFHX4 as a master regulator of CHD4. These observations define ZFHX4 as a regulatory factor that links the chromatin-remodeling NuRD complex and the GBM TIC state.

v-src induction of the TIS10/PGS2 prostaglandin synthase gene is mediated by an ATF/CRE transcription response element.

OpenAIRE

Xie, W; Fletcher, B S; Andersen, R D; Herschman, H R

1994-01-01

We recently reported the cloning of a mitogen-inducible prostaglandin synthase gene, TIS10/PGS2. In addition to growth factors and tumor promoters, the v-src oncogene induces TIS10/PGS2 expression in 3T3 cells. Deletion analysis, using luciferase reporters, identifies a region between -80 and -40 nucleotides 5' of the TIS10/PGS2 transcription start site that mediates pp60v-src induction in 3T3 cells. This region contains the sequence CGTCACGTG, which includes overlapping ATF/CRE (CGTCA) and E...

Implementation and validation of the linear collider final focus prototype: ATF2 at KEK (Japan); Implementation et validation de la focalisation finale du collisionneur lineaire: ATF2 at KEK (Japan)

Energy Technology Data Exchange (ETDEWEB)

Renier, Y.

2010-06-15

The two linear collider projects (ILC and CLIC) require beam delivery systems with the same local chromaticity correction scheme in the final focus. ATF2 at KEK (Japan), an implementation of this scheme scaled down in energy, uses the beam extracted from ATF, which is one of the most successful damping rings in the world. The ATF2 goals are to prove the feasibility and the stability of the linear collider final focus system and to define and test the experimental correction procedures. The nominal beam sizes at the interaction point are 3 {mu}m horizontally and 37 nm vertically. The work in this thesis was started before the commissioning and covered its first year at KEK. At the beginning, we observed that the stripline BPMs were not working properly so we investigated their behavior in detail. The problem was characterized and later solved in 2010 by upgrading the electronics. We then developed an efficient procedure to check the modeling of the beam line, comparing measurements of transfer matrices to model predictions calculated on line. After obtaining a good agreement, we were able to successfully test the trajectory correction algorithm which had been developed, reducing the difference between BPM measurements and the target values down to 0.5 mm horizontally and 0.2 mm vertically. We also successfully developed an algorithm to reconstruct pulse to pulse beam trajectory fluctuations with sub-micron precision. This reconstruction also gave a precise determination of the energy fluctuation, allowing a global fit of the dispersion function along the beam line with a precision of a few mm. A simple and robust IP beam size tuning method using sextupoles displacements was also studied in simulation, whose performance indicates that, given some assumptions on the error level of the beam, convergence within 20% of the nominal beam size should be possible in 8 hours with a 80% probability. (author)

The Effects of IGF-1 on TNF-α-Treated DRG Neurons by Modulating ATF3 and GAP-43 Expression via PI3K/Akt/S6K Signaling Pathway.

Science.gov (United States)

Zhang, Lei; Yue, Yaping; Ouyang, Meishuo; Liu, Huaxiang; Li, Zhenzhong

2017-05-01

Upregulation of the pro-inflammatory cytokine tumor necrosis factor α (TNF-α) is involved in the development and progression of numerous neurological disorders. Recent reports have challenged the concept that TNF-α exhibits only deleterious effects of pro-inflammatory destruction, and have raised the awareness that it may play a beneficial role in neuronal growth and function in particular conditions, which prompts us to further investigate the role of this cytokine. Insulin-like growth factor-1 (IGF-1) is a cytokine possessing powerful neuroprotective effects in promoting neuronal survival, neuronal differentiation, neurite elongation, and neurite regeneration. The association of IGF-1 with TNF-α and the biological effects, produced by interaction of IGF-1 and TNF-α, on neuronal outgrowth status of primary sensory neurons are still to be clarified. In the present study, using an in vitro model of primary cultured rat dorsal root ganglion (DRG) neurons, we demonstrated that TNF-α challenge at different concentrations elicited diverse biological effects. Higher concentration of TNF-α (10 ng/mL) dampened neurite outgrowth, induced activating transcription factor 3 (ATF3) expression, reduced growth-associated protein 43 (GAP-43) expression, and promoted GAP-43 and ATF3 coexpression, which could be reversed by IGF-1 treatment; while lower concentration of TNF-α (1 ng/mL) promoted neurite sprouting, decreased ATF3 expression, increased GAP-43 expression, and inhibited GAP-43 and ATF3 coexpression, which could be potentiated by IGF-1 supplement. Moreover, IGF-1 administration restored the activation of Akt and p70 S6 kinase (S6K) suppressed by higher concentration of TNF-α (10 ng/mL) challenge. In contrast, lower concentration of TNF-α (1 ng/mL) had no significant effect on Akt or S6K activation, and IGF-1 administration activated these two kinases. The effects of IGF-1 were abrogated by phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002. These data

Measured thermal and fast neutron fluence rates for ATF-1 holders during ATR cycle 160A

International Nuclear Information System (INIS)

Walker, B. J.; Miller, D. T.

2017-01-01

This report contains the thermal (2200 m/s) and fast (E>1MeV) neutron fluence rate data for the ATF-1 holders located in core for ATR Cycle 160A which were measured by the Radiation Measurements Laboratory (RML).

Measured thermal and fast neutron fluence rates for ATF-1 holders during ATR cycle 160A

Energy Technology Data Exchange (ETDEWEB)

Walker, B. J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Miller, D. T. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2017-06-06

This report contains the thermal (2200 m/s) and fast (E>1MeV) neutron fluence rate data for the ATF-1 holders located in core for ATR Cycle 160A which were measured by the Radiation Measurements Laboratory (RML).

Factors that regulate embryonic gustatory development

Directory of Open Access Journals (Sweden)

Krimm Robin F

2007-09-01

Full Text Available Abstract Numerous molecular factors orchestrate the development of the peripheral taste system. The unique anatomy/function of the taste system makes this system ideal for understanding the mechanisms by which these factors function; yet the taste system is underutilized for this role. This review focuses on some of the many factors that are known to regulate gustatory development, and discusses a few topics where more work is needed. Some attention is given to factors that regulate epibranchial placode formation, since gustatory neurons are thought to be primarily derived from this region. Epibranchial placodes appear to arise from a pan-placodal region and a number of regulatory factors control the differentiation of individual placodes. Gustatory neuron differentiation is regulated by a series of transcription factors and perhaps bone morphongenic proteins (BMP. As neurons differentiate, they also proliferate such that their numbers exceed those in the adult, and this is followed by developmental death. Some of these cell-cycling events are regulated by neurotrophins. After gustatory neurons become post-mitotic, axon outgrowth occurs. Axons are guided by multiple chemoattractive and chemorepulsive factors, including semaphorins, to the tongue epithelium. Brain derived neurotrophic factor (BDNF, functions as a targeting factor in the final stages of axon guidance and is required for gustatory axons to find and innervate taste epithelium. Numerous factors are involved in the development of gustatory papillae including Sox-2, Sonic hedge hog and Wnt-β-catenin signaling. It is likely that just as many factors regulate taste bud differentiation; however, these factors have not yet been identified. Studies examining the molecular factors that regulate terminal field formation in the nucleus of the solitary tract are also lacking. However, it is possible that some of the factors that regulate geniculate ganglion development, outgrowth, guidance and

Fibroblast growth factor 21 and its novel association with oxidative stress

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Miguel Ángel Gómez-Sámano

2017-04-01

Full Text Available Fibroblast growth factor 21 (FGF21 is an endocrine-member of the FGF family. It is synthesized mainly in the liver, but it is also expressed in adipose tissue, skeletal muscle, and many other organs. It has a key role in glucose and lipid metabolism, as well as in energy balance. FGF21 concentration in plasma is increased in patients with obesity, insulin resistance, and metabolic syndrome. Recent findings suggest that such increment protects tissue from an increased oxidative stress environment. Different types of physical stress, such as strenuous exercising, lactation, diabetic nephropathy, cardiovascular disease, and critical illnesses, also increase FGF21 circulating concentration. FGF21 is now considered a stress-responsive hormone in humans. The discovery of an essential response element in the FGF21 gene, for the activating transcription factor 4 (ATF4, involved in the regulation of oxidative stress, and its relation with genes such as NRF2, TBP-2, UCP3, SOD2, ERK, and p38, places FGF21 as a key regulator of the oxidative stress cell response. Its role in chronic diseases and its involvement in the treatment and follow-up of these diseases has been recently the target of new studies. The diminished oxidative stress through FGF21 pathways observed with anti-diabetic therapy is another clue of the new insights of this hormone.

Experimental and Theoretical Progress of Linear Collider Final Focus Design and ATF2 Facility

CERN Document Server

Seryi, Andrei; Zimmermann, Frank; Kubo, Kiyoshi; Kuroda, Shigeru; Okugi, Toshiyuki; Tauchi, Toshiaki; Terunuma, Nobuhiro; Urakawa, Junji; White, Glen; Woodley, Mark; Angal-Kalinin, Deepa

2014-01-01

In this brief overview we will reflect on the process of the design of the linear collider (LC) final focus (FF) optics, and will also describe the theoretical and experimental efforts on design and practical realisation of a prototype of the LC FF optics implemented in the ATF2 facility at KEK, Japan, presently being commissioned and operated.

A basic helix-loop-helix transcription factor, PhFBH4, regulates flower senescence by modulating ethylene biosynthesis pathway in petunia

Science.gov (United States)

The basic helix-loop-helix (bHLH) transcription factors (TFs) play important roles in regulating multiple biological processes in plants. However, there are few reports about the function of bHLHs in flower senescence. In this study, a bHLH TF, PhFBH4, was found to be dramatically upregulated during...

O-GlcNAc transferase regulates transcriptional activity of human Oct4.

Science.gov (United States)

Constable, Sandii; Lim, Jae-Min; Vaidyanathan, Krithika; Wells, Lance

2017-10-01

O-linked β-N-acetylglucosamine (O-GlcNAc) is a single sugar modification found on many different classes of nuclear and cytoplasmic proteins. Addition of this modification, by the enzyme O-linked N-acetylglucosamine transferase (OGT), is dynamic and inducible. One major class of proteins modified by O-GlcNAc is transcription factors. O-GlcNAc regulates transcription factor properties through a variety of different mechanisms including localization, stability and transcriptional activation. Maintenance of embryonic stem (ES) cell pluripotency requires tight regulation of several key transcription factors, many of which are modified by O-GlcNAc. Octamer-binding protein 4 (Oct4) is one of the key transcription factors required for pluripotency of ES cells and more recently, the generation of induced pluripotent stem (iPS) cells. The action of Oct4 is modulated by the addition of several post-translational modifications, including O-GlcNAc. Previous studies in mice found a single site of O-GlcNAc addition responsible for transcriptional regulation. This study was designed to determine if this mechanism is conserved in humans. We mapped 10 novel sites of O-GlcNAc attachment on human Oct4, and confirmed a role for OGT in transcriptional activation of Oct4 at a site distinct from that found in mouse that allows distinction between different Oct4 target promoters. Additionally, we uncovered a potential new role for OGT that does not include its catalytic function. These results confirm that human Oct4 activity is being regulated by OGT by a mechanism that is distinct from mouse Oct4. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Localisation of beam offset jitter sources at ATF2

CERN Document Server

Pfingstner, J; Patecki, M; Schulte, D; Tomás, R

2014-01-01

For the commissioning and operation of modern particle accelerators, automated error detection and diagnostics methods are becoming increasingly important. In this paper, we present two such methods, which are capable of localising sources of beam offset jitter with a combination of correlation studies and so called degree of freedom plots. The methods were applied to the ATF2 beam line at KEK, where one of the major goals is the reduction of the beam offset jitter. Results of this localisation are shown in this paper. A big advantage of the presented method is its high robustness especially to varying optics parameters. Therefore, we believe that the developed beam offset jitter localisation methods can be easily applied to other accelerators.

The translation initiation factor eIF4E regulates the sex-specific expression of the master switch gene Sxl in Drosophila melanogaster.

Directory of Open Access Journals (Sweden)

Patricia L Graham

2011-07-01

Full Text Available In female fruit flies, Sex-lethal (Sxl turns off the X chromosome dosage compensation system by a mechanism involving a combination of alternative splicing and translational repression of the male specific lethal-2 (msl-2 mRNA. A genetic screen identified the translation initiation factor eif4e as a gene that acts together with Sxl to repress expression of the Msl-2 protein. However, eif4e is not required for Sxl mediated repression of msl-2 mRNA translation. Instead, eif4e functions as a co-factor in Sxl-dependent female-specific alternative splicing of msl-2 and also Sxl pre-mRNAs. Like other factors required for Sxl regulation of splicing, eif4e shows maternal-effect female-lethal interactions with Sxl. This female lethality can be enhanced by mutations in other co-factors that promote female-specific splicing and is caused by a failure to properly activate the Sxl-positive autoregulatory feedback loop in early embryos. In this feedback loop Sxl proteins promote their own synthesis by directing the female-specific alternative splicing of Sxl-Pm pre-mRNAs. Analysis of pre-mRNA splicing when eif4e activity is compromised demonstrates that Sxl-dependent female-specific splicing of both Sxl-Pm and msl-2 pre-mRNAs requires eif4e activity. Consistent with a direct involvement in Sxl-dependent alternative splicing, eIF4E is associated with unspliced Sxl-Pm pre-mRNAs and is found in complexes that contain early acting splicing factors--the U1/U2 snRNP protein Sans-fils (Snf, the U1 snRNP protein U1-70k, U2AF38, U2AF50, and the Wilms' Tumor 1 Associated Protein Fl(2d--that have been directly implicated in Sxl splicing regulation.

Cross-talk between Smad and p38 MAPK signalling in transforming growth factor β signal transduction in human glioblastoma cells

International Nuclear Information System (INIS)

Dziembowska, Magdalena; Danilkiewicz, Malgorzata; Wesolowska, Aleksandra; Zupanska, Agata; Chouaib, Salem; Kaminska, Bozena

2007-01-01

Transforming growth factor-beta (TGF-β) is a multifunctional cytokine involved in the regulation of cell proliferation, differentiation, and survival. Malignant tumour cells often do not respond to TGF-β by growth inhibition, but retain responsiveness to cytokine in regulating extracellular matrix deposition, cell adhesion, and migration. We demonstrated that TGF-β1 does not affect viability or proliferation of human glioblastoma T98G, but increases transcriptional responses exemplified by induction of MMP-9 expression. TGF-β receptors were functional in T98G glioblastoma cells leading to SMAD3/SMAD4 nuclear translocation and activation of SMAD-dependent promoter. In parallel, a selective activation of p38 MAPK, and phosphorylation of its substrates: ATF2 and c-Jun proteins were followed by a transient activation of AP-1 transcription factor. Surprisingly, an inhibition of p38 MAPK with a specific inhibitor, SB202190, abolished TGF-inducible activation of Smad-dependent promoter and decreased Smad2 phosphorylation. It suggests an unexpected interaction between Smad and p38 MAPK pathways in TGF-β1-induced signalling

A Bifunctional Intronic Element Regulates the Expression of the Arginine/Lysine Transporter Cat-1 via Mechanisms Involving the Purine-rich Element Binding Protein A (Purα)*

Science.gov (United States)

Huang, Charlie C.; Chiribau, Calin-Bogdan; Majumder, Mithu; Chiang, Cheng-Ming; Wek, Ronald C.; Kelm, Robert J.; Khalili, Kamel; Snider, Martin D.; Hatzoglou, Maria

2009-01-01

Expression of the arginine/lysine transporter Cat-1 is highly induced in proliferating and stressed cells via mechanisms that include transcriptional activation. A bifunctional INE (intronic element) within the first intron of the Cat-1 gene was identified and characterized in this study. The INE had high sequence homology to an amino acid response element and was shown to act as a transcriptional enhancer in unstressed cells by binding the transcription factor, purine-rich element binding protein A (Purα). During endoplasmic reticulum stress, binding of Purα to the INE decreased; the element acted as a positive regulator in early stress by binding of the transcription factor ATF4 and as a negative regulator in prolonged stress by binding the stress-induced C/EBP family member, CHOP. We conclude that transcriptional control of the Cat-1 gene is tightly controlled by multiple cis-DNA elements, contributing to regulation of cationic amino acid transport for cell growth and proliferation. In addition, we propose that genes may use stress-response elements such as the INE to support basal expression in the absence of stress. PMID:19720825

Overview of results from the ATF torsatron

International Nuclear Information System (INIS)

Colchin, R.J.; Murakami, M.; Anabitarte, E.; Anderson, F.S.B.; Bell, G.L.; Bell, J.D.; Bigelow, T.S.; Crume, E.C.; Dunlap, J.L.; Dyer, G.R.; England, A.C.; Fisher, P.W.; Gabbard, W.A.; Glowienka, J.C.; Goulding, R.H.; Halliwell, J.W.; Hanson, G.R.; Harris, J.H.; Haste, G.R.; Hidalgo-Vera, C.; Hillis, D.L.; Hiroe, S.; Horton, L.D.; Howe, H.C.; Hutchinson, D.P.; Isler, R.C.; Jernigan, T.C.; Kwon, M.; Langley, R.A.; Lee, D.K.; Lyon, J.F.; Lue, J.W.; Ma, C.H.; Menon, M.M.; Morris, R.N.; Mioduszewski, P.K.; Neilson, G.H.; Qualls, A.L.; Rasmussen, D.A.; Rogers, P.S.; Shaw, P.L.; Shepard, T.D.; Simpkins, J.E.; Sudo, S.; Thomas, C.E.; Uckan, T.; Wade, M.R.; Wilgen, J.B.; Wing, W.R.; Yamada, H.; Zielinski, J.J.

1990-01-01

Experiments involving plasma improvement, confinement scaling, bootstrap currents, and edge fluctuations have been carried out in the Advanced Toroidal Facility (ATF) torsatron [Fusion Technol. 10, 179 (1986)]. Average densities bar n e ≤9x10 19 m -3 have been obtained, with global energy confinement times τ * E ≤20 msec. Confinement times generally follow the stellarator/torsatron empirical scaling law, τ SL =0.17xP -0.58 n 0.69 e B 0.84 a 2 R 0.75 (with τ SL in seconds, power P in megawatts, density n e in 10 20 m -3 , and plasma radius a and major radius R in meters). Gas injection during neutral beam injection (NBI) causes increases in n e , so that τ * E does not decrease during NBI. Edge plasma fluctuations are found to exhibit a mode change near the peak of the energy confinement time. Plasma currents observed during electron cyclotron heating have been identified as bootstrap currents

Induction of the unfolded protein response by cigarette smoke is primarily an activating transcription factor 4-C/EBP homologous protein mediated process

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Geraghty P

2011-06-01

Full Text Available Patrick Geraghty, Alison Wallace, Jeanine M D'ArmientoDepartment of Medicine, Divisions of Molecular and Pulmonary Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USAPurpose: Cigarette smoke is the major risk factor associated with the development of chronic obstructive pulmonary disease (COPD. Recent studies propose a link between endoplasmic reticulum (ER stress and emphysema, demonstrated by increased ER stress markers under smoking conditions. Here, we investigate whether cigarette smoke-induced ER stress is cell specific and correlates with acute and chronic cigarette smoke exposure.Methods: Gene and protein expression changes in human primary lung cell cultures following cigarette smoke extract (CSE exposure were monitored by qPCR and Western blot analysis. Mice and guinea pigs were exposed to cigarette smoke and ER stress markers examined in whole lung homogenates. Inflammatory cells from the bronchoalveolar lavage fluid of 10 days smoke exposed mice were also examined.Results: Cigarette smoke induced a trend increase in the ER stress response through an activating transcription factor 4 (ATF4 mediated induction of C/EBP homologous protein (CHOP in primary small airway epithelial cells. Bronchial epithelial cells and macrophages responded similarly to CSE. Wild-type mice and guinea pigs exposed to acute levels of cigarette smoke exhibited increased levels of CHOP but not at significant levels. However, after long-term chronic cigarette smoke exposure, CHOP expression was reduced. Interestingly, inflammatory cells from smoke exposed mice had a significant increase in CHOP/ATF4 expression.Conclusion: A trend increase in CHOP levels appear in multiple human lung cell types following acute cigarette smoke exposure in vitro. In vivo, inflammatory cells, predominately macrophages, demonstrate significant cigarette smoke-induced ER stress. Early induction of CHOP in cigarette smoke may play a pivotal role in early

Preliminary neutronic assessment for ATF (Accident Tolerant Fuel) based on iron alloy

International Nuclear Information System (INIS)

Abe, Alfredo; Carluccio, Thiago; Piovezan, Pamela; Giovedi, Claudia; Martins, Marcelo R.

2015-01-01

After Fukushima Daiichi nuclear accident in 2011, the nuclear fuel performance under accident condition became a very important issue and currently different research and development program are in progress toward to reliability and withstand under accident condition. These initiatives are known as ATF (Accident Tolerant Fuel) R and D program, which many countries with different research institutes, fuel vendors and others are nowadays involved. Accident Tolerant Fuel (ATF) can be defined as enhanced fuel which can tolerate loss of active cooling system capability for a considerably longer time period and the fuel/cladding system can be maintained without significant degradation and can also improve the fuel performance during normal operations and transients, as well as design-basis accident (DBA) and beyond design-basis (BDBA) accident. Different materials have being proposed as fuel cladding candidates considering thermo-mechanical properties and lower reaction kinetic with steam and slower hydrogen production. The aim of this work is to perform a neutronic assessment for several cladding candidates based on iron alloy considering a standard PWR fuel rod (fuel pellet and dimension). The purpose of the assessment is to address different parameters that might contribute for possible neutronic reactivity gain in order to overcome the penalty due to increase of neutron absorption in the cladding materials. All the neutronic assessment is performed using MCNP, Monte Carlo code. (author)

Summary of the U.S. National Workshop. Results for ATF Metrics Development

International Nuclear Information System (INIS)

Pasamehmetoglu, Kemal

2013-01-01

This presentation discussed the main outcomes of a recent US National Workshop on Accident-Tolerant Fuels, focusing on results for ATF metrics development. All thermal, mechanical and chemical properties are relevant in defining the metrics for accident tolerance, but considerable testing and analyses are needed to identify the dominant attributes and quantify the metrics. Current analysis tools are not fully adequate to complete the task, and a need was highlighted for strong collaborations to complete the experimental data to qualify the new tools

Fluctuations and stability in the Advanced Toroidal Facility (ATF) torsatron

International Nuclear Information System (INIS)

Harris, J.H.; Charlton, L.A.; Bell, J.D.; Bigelow, T.S.; Carreras, B.A.; Colchin, R.J.; Crume, E.C.; Dominguez, N.; Dunlap, J.L.; Dyer, G.R.; England, A.C.; Glowienka, J.C.; Hillis, D.L.; Hiroe, S.; Horton, L.D.; Howe, H.C.; Isler, R.C.; Jernigan, T.C.; Leboeuf, J.N.; Lee, D.K.; Lynch, V.E.; Lyon, J.F.; Menon, M.M.; Murakami, M.; Rasmussen, D.A.; Uckan, T.; Wilgen, J.B.; Wing, W.R.; Bell, G.L.; Crocker, N.A.; Hanson, G.R.; Thomas, C.E.; Wade, M.R.; Ritz, C.P.

1990-01-01

We present the results of experimental and theoretical studies of fluctuations and instabilities in the ATF torsatron, a type of stellarator. Measurements of globally coherent magnetic fluctuations in high-β plasmas with narrow pressure profiles produced by a field error show evidence of self-stabilization ('second stability'); the trends are compatible with theoretical analysis of self-stabilization of resistive curvature-driven instabilities, but there are discrepancies between the absolute experimental and theoretical fluctuation amplitudes. Fluctuation measurements in plasma with broad pressure profiles reveal new phenomena--specifically, toroidally localized magnetic fluctuations, whose amplitudes increase with plasma pressure, and coherent density fluctuations with significant radial width

The artificial gene Jazz, a transcriptional regulator of utrophin, corrects the dystrophic pathology in mdx mice.

Science.gov (United States)

Di Certo, Maria Grazia; Corbi, Nicoletta; Strimpakos, Georgios; Onori, Annalisa; Luvisetto, Siro; Severini, Cinzia; Guglielmotti, Angelo; Batassa, Enrico Maria; Pisani, Cinzia; Floridi, Aristide; Benassi, Barbara; Fanciulli, Maurizio; Magrelli, Armando; Mattei, Elisabetta; Passananti, Claudio

2010-03-01

The absence of the cytoskeletal protein dystrophin results in Duchenne muscular dystrophy (DMD). The utrophin protein is the best candidate for dystrophin replacement in DMD patients. To obtain therapeutic levels of utrophin expression in dystrophic muscle, we developed an alternative strategy based on the use of artificial zinc finger transcription factors (ZF ATFs). The ZF ATF 'Jazz' was recently engineered and tested in vivo by generating a transgenic mouse specifically expressing Jazz at the muscular level. To validate the ZF ATF technology for DMD treatment we generated a second mouse model by crossing Jazz-transgenic mice with dystrophin-deficient mdx mice. Here, we show that the artificial Jazz protein restores sarcolemmal integrity and prevents the development of the dystrophic disease in mdx mice. This exclusive animal model establishes the notion that utrophin-based therapy for DMD can be efficiently developed using ZF ATF technology and candidates Jazz as a novel therapeutic molecule for DMD therapy.

Genetic Regulation of Virulence and Antibiotic Resistance in Acinetobacter baumannii

Science.gov (United States)

Kröger, Carsten; Kary, Stefani C.; Schauer, Kristina; Cameron, Andrew D. S.

2016-01-01

Multidrug resistant microorganisms are forecast to become the single biggest challenge to medical care in the 21st century. Over the last decades, members of the genus Acinetobacter have emerged as bacterial opportunistic pathogens, in particular as challenging nosocomial pathogens because of the rapid evolution of antimicrobial resistances. Although we lack fundamental biological insight into virulence mechanisms, an increasing number of researchers are working to identify virulence factors and to study antibiotic resistance. Here, we review current knowledge regarding the regulation of virulence genes and antibiotic resistance in Acinetobacter baumannii. A survey of the two-component systems AdeRS, BaeSR, GacSA and PmrAB explains how each contributes to antibiotic resistance and virulence gene expression, while BfmRS regulates cell envelope structures important for pathogen persistence. A. baumannii uses the transcription factors Fur and Zur to sense iron or zinc depletion and upregulate genes for metal scavenging as a critical survival tool in an animal host. Quorum sensing, nucleoid-associated proteins, and non-classical transcription factors such as AtfA and small regulatory RNAs are discussed in the context of virulence and antibiotic resistance. PMID:28036056

The long non-coding RNA GAS5 cooperates with the eukaryotic translation initiation factor 4E to regulate c-Myc translation.

Directory of Open Access Journals (Sweden)

Guangzhen Hu

Full Text Available Long noncoding RNAs (lncRNAs are important regulators of transcription; however, their involvement in protein translation is not well known. Here we explored whether the lncRNA GAS5 is associated with translation initiation machinery and regulates translation. GAS5 was enriched with eukaryotic translation initiation factor-4E (eIF4E in an RNA-immunoprecipitation assay using lymphoma cell lines. We identified two RNA binding motifs within eIF4E protein and the deletion of each motif inhibited the binding of GAS5 with eIF4E. To confirm the role of GAS5 in translation regulation, GAS5 siRNA and in vitro transcribed GAS5 RNA were used to knock down or overexpress GAS5, respectively. GAS5 siRNA had no effect on global protein translation but did specifically increase c-Myc protein level without an effect on c-Myc mRNA. The mechanism of this increase in c-Myc protein was enhanced association of c-Myc mRNA with the polysome without any effect on protein stability. In contrast, overexpression of in vitro transcribed GAS5 RNA suppressed c-Myc protein without affecting c-Myc mRNA. Interestingly, GAS5 was found to be bound with c-Myc mRNA, suggesting that GAS5 regulates c-Myc translation through lncRNA-mRNA interaction. Our findings have uncovered a role of GAS5 lncRNA in translation regulation through its interactions with eIF4E and c-Myc mRNA.

Activating transcription factor 6 polymorphisms and haplotypes are associated with impaired glucose homeostasis and type 2 diabetes in dutch Caucasians

NARCIS (Netherlands)

Meex, Steven J. R.; van Greevenbroek, Marleen M. J.; Ayoubi, Torik A.; Vlietinck, Robert; van Vliet-Ostaptchouk, Jana V.; Hofker, Martin H.; Vermeulen, Vicky M. M. -J.; Schalkwijk, Casper G.; Feskens, Edith J. M.; Boer, Jolanda M. A.; Stehouwer, Coen D. A.; van der Kallen, Carla J. H.; de Bruin, Tjerk W. A.

Context: Activating transcription factor 6 (ATF6) is critical for initiation and full activation of the unfolded protein response. An association between genetic variation in ATF6 and type 2 diabetes (DM2) was recently reported in Pima Indians. Objectives: To investigate the broader significance of

FOXO1 orchestrates the bone-suppressing function of gut-derived serotonin

Science.gov (United States)

Kode, Aruna; Mosialou, Ioanna; Silva, Barbara C.; Rached, Marie-Therese; Zhou, Bin; Wang, Ji; Townes, Tim M.; Hen, Rene; DePinho, Ronald A.; Guo, X. Edward; Kousteni, Stavroula

2012-01-01

Serotonin is a critical regulator of bone mass, fulfilling different functions depending on its site of synthesis. Brain-derived serotonin promotes osteoblast proliferation, whereas duodenal-derived serotonin suppresses it. To understand the molecular mechanisms of duodenal-derived serotonin action on osteoblasts, we explored its transcriptional mediation in mice. We found that the transcription factor FOXO1 is a crucial determinant of the effects of duodenum-derived serotonin on bone formation We identified two key FOXO1 complexes in osteoblasts, one with the transcription factor cAMP-responsive element–binding protein 1 (CREB) and another with activating transcription factor 4 (ATF4). Under normal levels of circulating serotonin, the proliferative activity of FOXO1 was promoted by a balance between its interaction with CREB and ATF4. However, high circulating serotonin levels prevented the association of FOXO1 with CREB, resulting in suppressed osteoblast proliferation. These observations identify FOXO1 as the molecular node of an intricate transcriptional machinery that confers the signal of duodenal-derived serotonin to inhibit bone formation. PMID:22945629

Amino alcohol- (NPS-2143 and quinazolinone-derived calcilytics (ATF936 and AXT914 differentially mitigate excessive signalling of calcium-sensing receptor mutants causing Bartter syndrome Type 5 and autosomal dominant hypocalcemia.

Directory of Open Access Journals (Sweden)

Saskia Letz

Full Text Available Activating calcium sensing receptor (CaSR mutations cause autosomal dominant hypocalcemia (ADH characterized by low serum calcium, inappropriately low PTH and relative hypercalciuria. Four activating CaSR mutations cause additional renal wasting of sodium, chloride and other salts, a condition called Bartter syndrome (BS type 5. Until today there is no specific medical treatment for BS type 5 and ADH. We investigated the effects of different allosteric CaSR antagonists (calcilytics on activating CaSR mutants.All 4 known mutations causing BS type 5 and five ADH mutations were expressed in HEK 293T cells and receptor signalling was studied by measurement of intracellular free calcium in response to extracellular calcium ([Ca2+]o. To investigate the effect of calcilytics, cells were stimulated with 3 mM [Ca2+]o in the presence or absence of NPS-2143, ATF936 or AXT914.All BS type 5 and ADH mutants showed enhanced signalling activity to [Ca2+]o with left shifted dose response curves. In contrast to the amino alcohol NPS-2143, which was only partially effective, the quinazolinone calcilytics ATF936 and AXT914 significantly mitigated excessive cytosolic calcium signalling of all BS type 5 and ADH mutants studied. When these mutants were co-expressed with wild-type CaSR to approximate heterozygosity in patients, ATF936 and AXT914 were also effective on all mutants.The calcilytics ATF936 and AXT914 are capable of attenuating enhanced cytosolic calcium signalling activity of CaSR mutations causing BS type 5 and ADH. Quinazolinone calcilytics might therefore offer a novel treatment option for patients with activating CaSR mutations.

CXC chemokine receptor 4 expression and stromal cell-derived factor-1alpha-induced chemotaxis in CD4+ T lymphocytes are regulated by interleukin-4 and interleukin-10

DEFF Research Database (Denmark)

Jinquan, T; Quan, S; Jacobi, H H

2000-01-01

-10. IL-4 and IL-10 up- or down-regulated CXCR4 mRNA expression in CD4+ T lymphocytes, respectively, as detected by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR). Scatchard analysis revealed a type of CXCR4 with affinity (Kd approximately 6.3 nM), and approximately 70....... The regulation of CXCR4 expression in CD4+ T lymphocytes by IL-4 and IL-10 could be blocked by a selective inhibitor of protein kinase (staurosporine) or by a selective inhibitor of cAMP- and cGMP-dependent protein kinase (H-8), indicating that these cytokines regulate CXCR4 on CD4+ T lymphocytes via both c......AMP and cGMP signalling pathways. The fact that cyclosporin A or ionomycin were able to independently change the CXCR4 expression and block the effects of IL-4 and IL-10 on CXCR4 expression implied that the capacity of IL-4 and IL-10 to regulate CXCR4 on CD4+ T lymphocytes is not linked to calcium...

ABI4 regulates primary seed dormancy by regulating the biogenesis of abscisic acid and gibberellins in arabidopsis.

Directory of Open Access Journals (Sweden)

Kai Shu

2013-06-01

Full Text Available Seed dormancy is an important economic trait for agricultural production. Abscisic acid (ABA and Gibberellins (GA are the primary factors that regulate the transition from dormancy to germination, and they regulate this process antagonistically. The detailed regulatory mechanism involving crosstalk between ABA and GA, which underlies seed dormancy, requires further elucidation. Here, we report that ABI4 positively regulates primary seed dormancy, while negatively regulating cotyledon greening, by mediating the biogenesis of ABA and GA. Seeds of the Arabidopsis abi4 mutant that were subjected to short-term storage (one or two weeks germinated significantly more quickly than Wild-Type (WT, and abi4 cotyledons greened markedly more quickly than WT, while the rates of germination and greening were comparable when the seeds were subjected to longer-term storage (six months. The ABA content of dry abi4 seeds was remarkably lower than that of WT, but the amounts were comparable after stratification. Consistently, the GA level of abi4 seeds was increased compared to WT. Further analysis showed that abi4 was resistant to treatment with paclobutrazol (PAC, a GA biosynthesis inhibitor, during germination, while OE-ABI4 was sensitive to PAC, and exogenous GA rescued the delayed germination phenotype of OE-ABI4. Analysis by qRT-PCR showed that the expression of genes involved in ABA and GA metabolism in dry and germinating seeds corresponded to hormonal measurements. Moreover, chromatin immunoprecipitation qPCR (ChIP-qPCR and transient expression analysis showed that ABI4 repressed CYP707A1 and CYP707A2 expression by directly binding to those promoters, and the ABI4 binding elements are essential for this repression. Accordingly, further genetic analysis showed that abi4 recovered the delayed germination phenotype of cyp707a1 and cyp707a2 and further, rescued the non-germinating phenotype of ga1-t. Taken together, this study suggests that ABI4 is a key

Krüppel-like factor 4, a novel transcription factor regulates microglial activation and subsequent neuroinflammation

Directory of Open Access Journals (Sweden)

Das Sulagna

2010-10-01

Full Text Available Abstract Background Activation of microglia, the resident macrophages of the central nervous system (CNS, is the hallmark of neuroinflammation in neurodegenerative diseases and other pathological conditions associated with CNS infection. The activation of microglia is often associated with bystander neuronal death. Nuclear factor-κB (NF-κB is one of the important transcription factors known to be associated with microglial activation which upregulates the expression of inducible nitric oxide synthase (iNOS, cyclooxygenase-2 (Cox-2 and other pro-inflammatory cytokines. Recent studies have focused on the role of Krüppel-like factor 4 (Klf4, one of the zinc-finger transcription factors, in mediating inflammation. However, these studies were limited to peripheral system and its role in CNS is not understood. Our studies focused on the possible role of Klf4 in mediating CNS inflammation. Methods For in vitro studies, mouse microglial BV-2 cell lines were treated with 500 ng/ml Salmonella enterica lipopolysacchride (LPS. Brain tissues were isolated from BALB/c mice administered with 5 mg/kg body weight of LPS. Expressions of Klf4, Cox-2, iNOS and pNF-κB were evaluated using western blotting, quantitative real time PCR, and reverse transcriptase polymerase chain reactions (RT-PCRs. Klf4 knockdown was carried out using SiRNA specific for Klf4 mRNA and luciferase assays and electromobility shift assay (EMSA were performed to study the interaction of Klf4 to iNOS promoter elements in vitro. Co-immunoprecipitation of Klf4 and pNF-κB was done in order to study a possible interaction between the two transcription factors. Results LPS stimulation increased Klf4 expression in microglial cells in a time- and dose-dependent manner. Knockdown of Klf4 resulted in decreased levels of the pro-inflammatory cytokines TNF-α, MCP-1 and IL-6, along with a significant decrease in iNOS and Cox-2 expression. NO production also decreased as a result of Klf4 knockdown

Carboxylesterase 1 Is Regulated by Hepatocyte Nuclear Factor 4α and Protects Against Alcohol- and MCD diet-induced Liver Injury.

Science.gov (United States)

Xu, Jiesi; Xu, Yang; Li, Yuanyuan; Jadhav, Kavita; You, Min; Yin, Liya; Zhang, Yanqiao

2016-04-14

The liver is a major organ that controls hepatic and systemic homeostasis. Dysregulation of liver metabolism may cause liver injury. Previous studies have demonstrated that carboxylesterase 1 (CES1) regulates hepatic triglyceride metabolism and protects against liver steatosis. In the present study, we investigated whether CES1 played a role in the development of alcoholic liver disease (ALD) and methionine and choline-deficient (MCD) diet-induced liver injury. Both hepatocyte nuclear factor 4α (HNF4α) and CES1 were markedly reduced in patients with alcoholic steatohepatitis. Alcohol repressed both HNF4α and CES1 expression in primary hepatocytes. HNF4α regulated CES1 expression by directly binding to the proximal promoter of CES1. Global inactivation of CES1 aggravated alcohol- or MCD diet-induced liver inflammation and liver injury, likely as a result of increased production of acetaldehyde and reactive oxygen species and mitochondrial dysfunctions. Knockdown of hepatic CES1 exacerbated ethanol-induced steatohepatitis. These data indicate that CES1 plays a crucial role in protection against alcohol- or MCD diet-induced liver injury.

Chemical chaperon 4-phenylbutyrate protects against the endoplasmic reticulum stress-mediated renal fibrosis in vivo and in vitro.

Science.gov (United States)

Liu, Shing-Hwa; Yang, Ching-Chin; Chan, Ding-Cheng; Wu, Cheng-Tien; Chen, Li-Ping; Huang, Jenq-Wen; Hung, Kuan-Yu; Chiang, Chih-Kang

2016-04-19

Renal tubulointerstitial fibrosis is the common and final pathologic change of kidney in end-stage renal disease. Interesting, endoplasmic reticulum (ER) stress is known to contribute to the pathophysiological mechanisms during the development of renal fibrosis. Here, we investigated the effects of chemical chaperon sodium 4-phenylbutyrate (4-PBA) on renal fibrosis in vivo and in vitro. In a rat unilateral ureteral obstruction (UUO) model, 4-PBA mimicked endogenous ER chaperon in the kidneys and significantly reduced glucose regulated protein 78 (GRP78), CCAAT/enhancer binding protein (C/EBP) homologous protein (CHOP), activating transcription factor 4 (ATF4), and phosphorylated JNK protein expressions as well as restored spliced X-box-binding protein 1 (XBP1) expressions in the kidneys of UUO rats. 4-PBA also attenuated the increases of α-smooth muscle actin (α-SMA), connective tissue growth factor (CTGF) protein expressions, tubulointerstitial fibrosis, and apoptosis in the kidneys of UUO rats. Moreover, transforming growth factor (TGF)-β markedly increased ER stress-associated molecules, profibrotic factors, and apoptotic markers in the renal tubular cells (NRK-52E), all of which could be significantly counteracted by 4-PBA treatment. 4-PBA also diminished TGF-β-increased CTGF promoter activity and CTGF mRNA expression in NRK-52E cells. Taken together, our results indicated that 4-PBA acts as an ER chaperone to ameliorate ER stress-induced renal tubular cell apoptosis and renal fibrosis.

Measured thermal and fast neutron fluence rates for ATF-1 holders during ATR cycle 158B/159A

Energy Technology Data Exchange (ETDEWEB)

Smith, Larry Don [Idaho National Lab. (INL), Idaho Falls, ID (United States); Miller, David Torbet [Idaho National Lab. (INL), Idaho Falls, ID (United States); Walker, Billy Justin [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2016-11-01

This report contains the thermal (2200 m/s) and fast (E>1MeV) neutron fluence rate data for the ATF-1 holders located in core for ATR Cycle 158B/159A which were measured by the Radiation Measurements Laboratory (RML).

Regulation of Na(+)/K(+)-ATPase by neuron-specific transcription factor Sp4: implication in the tight coupling of energy production, neuronal activity and energy consumption in neurons.

Science.gov (United States)

Johar, Kaid; Priya, Anusha; Wong-Riley, Margaret T T

2014-02-01

A major source of energy demand in neurons is the Na(+)/K(+)-ATPase pump that restores the ionic gradient across the plasma membrane subsequent to depolarizing neuronal activity. The energy comes primarily from mitochondrial oxidative metabolism, of which cytochrome c oxidase (COX) is a key enzyme. Recently, we found that all 13 subunits of COX are regulated by specificity (Sp) factors, and that the neuron-specific Sp4, but not Sp1 or Sp3, regulates the expression of key glutamatergic receptor subunits as well. The present study sought to test our hypothesis that Sp4 also regulates Na(+)/K(+)-ATPase subunit genes in neurons. By means of multiple approaches, including in silico analysis, electrophoretic mobility shift and supershift assays, chromatin immunoprecipitation, promoter mutational analysis, over-expression, and RNA interference studies, we found that Sp4, with minor contributions from Sp1 and Sp3, functionally regulate the Atp1a1, Atp1a3, and Atp1b1 subunit genes of Na(+)/K(+)-ATPase in neurons. Transcripts of all three genes were up-regulated by depolarizing KCl stimulation and down-regulated by the impulse blocker tetrodotoxin (TTX), indicating that their expression was activity-dependent. Silencing of Sp4 blocked the up-regulation of these genes induced by KCl, whereas over-expression of Sp4 rescued them from TTX-induced suppression. The effect of silencing or over-expressing Sp4 on primary neurons was much greater than those of Sp1 or Sp3. The binding sites of Sp factors on these genes are conserved among mice, rats and humans. Thus, Sp4 plays an important role in the transcriptional coupling of energy generation and energy consumption in neurons. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

High Resolution BPM Upgrade for the ATF Damping Ring at KEK

International Nuclear Information System (INIS)

Eddy, N.; Briegel, C.; Fellenz, B.; Gianfelice-Wendt, E.; Prieto, P.; Rechenmacher, R.; Semenov, A.; Voy, D.; Wendt, M.; Zhang, D.; Terunuma, N.

2011-01-01

A beam position monitor (BPM) upgrade at the KEK Accelerator Test Facility (ATF) damping ring has been accomplished, carried out by a KEK/FNAL/SLAC collaboration under the umbrella of the global ILC R and D effort. The upgrade consists of a high resolution, high reproducibility read-out system, based on analog and digital down-conversion techniques, digital signal processing, and also implements a new automatic gain error correction schema. The technical concept and realization as well as results of beam studies are presented. The next generation of linear colliders require ultra-low vertical emittance of <2 pm-rad. The damping ring at the KEK Accelerator Test Facility (ATF) is designed to demonstrate this mission critical goal. A high resolution beam position monitor (BPM) system for the damping ring is one of the key tools for realizing this goal. The BPM system needs to provide two distnict measurements. First, a very high resolution (∼100-200nm) closed-orbit measurement which is averaged over many turns and realized with narrowband filter techniques - 'narrowband mode'. This is needed to monitor and steer the beam along an optimum orbit and to facilitate beam-based alignment to minimize non-linear field effects. Second, is the ability to make turn by turn (TBT) measurements to support optics studies and corrections necessary to achieve the design performance. As the TBT measurement necessitates a wider bandwidth, it is often referred to as 'wideband mode'. The BPM upgrade was initiated as a KEK/SLAC/FNAL collaboration in the frame of the Global Design Initiative of the International Linear Collider. The project was realized and completed using Japan-US funds with Fermilab as the core partner.

The data acquisition and control system for Thomson Scattering on ATF [Advanced Toroidal Facility

International Nuclear Information System (INIS)

Stewart, K.A.; Kindsfather, R.R.; Rasmussen, D.A.

1989-01-01

The 2-dimensional Thomson Scattering System measuring electron temperatures and densities in the Advanced Toroidal Facility (ATF) is interfaced to a VAX-8700 computer system running in a clustered configuration. Calibration, alignment, and operation of this diagnostic is under computer control. Extensive CAMAC instrumentation is used for timing control, data acquisition, and laser alignment. This paper will discuss the computer hardware and software, system operations, and data storage and retrieval. 3 refs

PGC-1α in aging and lifelong exercise training-mediated regulation of UPR in mouse liver

DEFF Research Database (Denmark)

Maag Kristensen, Caroline; Brandt, Christina Tingbjerg; Jørgensen, Stine Ringholm

2017-01-01

of specific UPR pathways and increased activity of the ATF6 pathway in the liver with aging. Lifelong exercise training prevented the age-associated change in BiP and IRE1α protein, but not cleaved ATF6 protein and resulted in further decreased PERK protein. Taken together, the present study provides evidence...... that the capacity and activity of the three UPR pathways are differentially regulated in the liver with aging and lifelong exercise training. In addition, PGC-1α does not seem to regulate the activity of hepatic UPR in response to exercise training, but to influence the capacity of the liver to induce UPR......Aging is associated with changes in several metabolic pathways affecting liver function including the adaptive unfolded protein response (UPR). On the other hand, exercise training has been shown to exert beneficial effects on metabolism in the liver and exercise training has been reported...

Fatty Acid–Regulated Transcription Factors in the Liver

Science.gov (United States)

Jump, Donald B.; Tripathy, Sasmita; Depner, Christopher M.

2014-01-01

Fatty acid regulation of hepatic gene transcription was first reported in the early 1990s. Several transcription factors have been identified as targets of fatty acid regulation. This regulation is achieved by direct fatty acid binding to the transcription factor or by indirect mechanisms where fatty acids regulate signaling pathways controlling the expression of transcription factors or the phosphorylation, ubiquitination, or proteolytic cleavage of the transcription factor. Although dietary fatty acids are well-established regulators of hepatic transcription factors, emerging evidence indicates that endogenously generated fatty acids are equally important in controlling transcription factors in the context of glucose and lipid homeostasis. Our first goal in this review is to provide an up-to-date examination of the molecular and metabolic bases of fatty acid regulation of key transcription factors controlling hepatic metabolism. Our second goal is to link these mechanisms to nonalcoholic fatty liver disease (NAFLD), a growing health concern in the obese population. PMID:23528177

Implementation and validation of the linear collider final focus prototype: ATF2 at KEK (Japan)

International Nuclear Information System (INIS)

Renier, Y.

2010-06-01

The two linear collider projects (ILC and CLIC) require beam delivery systems with the same local chromaticity correction scheme in the final focus. ATF2 at KEK (Japan), an implementation of this scheme scaled down in energy, uses the beam extracted from ATF, which is one of the most successful damping rings in the world. The ATF2 goals are to prove the feasibility and the stability of the linear collider final focus system and to define and test the experimental correction procedures. The nominal beam sizes at the interaction point are 3 μm horizontally and 37 nm vertically. The work in this thesis was started before the commissioning and covered its first year at KEK. At the beginning, we observed that the stripline BPMs were not working properly so we investigated their behavior in detail. The problem was characterized and later solved in 2010 by upgrading the electronics. We then developed an efficient procedure to check the modeling of the beam line, comparing measurements of transfer matrices to model predictions calculated on line. After obtaining a good agreement, we were able to successfully test the trajectory correction algorithm which had been developed, reducing the difference between BPM measurements and the target values down to 0.5 mm horizontally and 0.2 mm vertically. We also successfully developed an algorithm to reconstruct pulse to pulse beam trajectory fluctuations with sub-micron precision. This reconstruction also gave a precise determination of the energy fluctuation, allowing a global fit of the dispersion function along the beam line with a precision of a few mm. A simple and robust IP beam size tuning method using sextupoles displacements was also studied in simulation, whose performance indicates that, given some assumptions on the error level of the beam, convergence within 20% of the nominal beam size should be possible in 8 hours with a 80% probability. (author)

25 CFR 275.4 - Implementing regulations.

Science.gov (United States)

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Implementing regulations. 275.4 Section 275.4 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR INDIAN SELF-DETERMINATION AND EDUCATION ASSISTANCE ACT PROGRAM STAFFING § 275.4 Implementing regulations. Regulations to implement section 105 of the Act...

Feedback system of the RF phase in KEK-ATF linac

Energy Technology Data Exchange (ETDEWEB)

Okugi, T.; Hayano, H.; Kuriki, M.; Naito, T. [Accelerator Laboratory, High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan)

2000-07-01

KEK-ATF linac is built in the Assembly Hall for TRISTAN project in 1991. The thermal condition of the hall is not good enough for a stable linac operation, because the temperature of the klystron gallery is drifted by 1degC within one day. RF phase is also drifted by 3-5deg of the S-band frequency in day and night. In order to control the RF phase, we installed RF phase detectors, which have S/H circuit in order to use for pulsed RF. By using the phase detector, an RF phase feedback system was tested. It was found that a stable klystron operation could be performed within the phase drift of {+-}0.5deg in a day. (author)

The role of ZmWRKY4 in regulating maize antioxidant defense under cadmium stress

International Nuclear Information System (INIS)

Hong, Changyong; Cheng, Dan; Zhang, Guoqiang; Zhu, Dandan; Chen, Yahua; Tan, Mingpu

2017-01-01

WRKY transcription factors act as positive regulators in abiotic stress responses by activation of the cellular antioxidant systems. However, there are few reports on the response of WRKY genes to cadmium (Cd) stress. In this study, the role of maize ZmWRKY4 in regulating antioxidant enzymes in Cd stress was investigated. The results indicated that Cd induced up-regulation of the expression and the activities of ZmWRKY4 and superoxide dismutase (SOD) and ascorbate peroxidase (APX). Transient expression and RNA interference (RNAi) silencing of ZmWRKY4 in maize mesophyll protoplasts further revealed that ZmWRKY4 was required for the abscisic acid (ABA)-induced increase in expression and activity of SOD and APX. Overexpression of ZmWRKY4 in protoplasts upregulated the expression and the activities of antioxidant enzymes, whereas ABA induced increases in the expression and the activities of antioxidant enzymes were blocked by the RNAi silencing of ZmWRKY4. Bioinformatic analysis indicated that ZmSOD4 and ZmcAPX both harbored two W-boxes, binding motif for WRKY transcription factors, in their promoter region. Intriguingly, ZmWRKY4 belongs to group I WRKYs with two WRKY domains. Moreover, the synchronized expression patterns indicate that ZmWRKY4 might play a critical role in either regulating the ZmSOD4 and ZmcAPX expression or cooperating with them in response to stress and phytohormone. - Highlights: • Cd induced the expression of ZmWRKY4, ZmSOD4 and ZmcAPX. • Maize transcription factor ZmWRKY4 was localized in nucleus. • Overexpression of ZmWRKY4 upregulated the expression of ZmSOD4 and ZmcAPX and the activities of antioxidant enzymes.

Experimental evidence of EDGE turbulence driven by multiple mechanisms in ATF

International Nuclear Information System (INIS)

Hidalgo, C.

1993-01-01

The scaling properties of edge fluctuations have been investigated using Langmuir probes in the edge region of the Advance Toroidal Facility (ATF). Fluctuations in the ion saturation current (ls/ls) and transport inferred from the fluctuations increase with increasing density gradient, while keeping unchanged local electron temperature. The modification of the electron temperature in the range (10-50) eV, Keeping constant the density profile, does not have any significant influence on ls/ ls. In regions were Er/B =0, the poloidal phase velocity of the fluctuations is given by vph 2Te/LnB. More then one of any so far proposed mechanisms must be invoked to explain all the experimental observations. (Author) 14 refs

Engineered zinc-finger transcription factors inhibit the replication and transcription of HBV in vitro and in vivo.

Science.gov (United States)

Luo, Wei; Wang, Junxia; Xu, Dengfeng; Bai, Huili; Zhang, Yangli; Zhang, Yuhong; Li, Xiaosong

2018-04-01

In the present study, an artificial zinc-finger transcription factor eukaryotic expression vector specifically recognizing and binding to the hepatitis B virus (HBV) enhancer (Enh) was constructed, which inhibited the replication and expression of HBV DNA. The HBV EnhI‑specific pcDNA3.1‑artificial transcription factor (ATF) vector was successfully constructed, and then transformed or injected into HepG2.2.15 cells and HBV transgenic mice, respectively. The results demonstrated that the HBV EnhI (1,070‑1,234 bp)‑specific ATF significantly inhibited the replication and transcription of HBV DNA in vivo and in vitro. The HBV EnhI‑specific ATF may be a meritorious component of progressive combination therapies for eliminating HBV DNA in infected patients. A radical cure for chronic HBV infection may become feasible by using this bioengineering technology.

Potential Role of Activating Transcription Factor 5 during Osteogenesis

Directory of Open Access Journals (Sweden)

Luisa Vicari

2016-01-01

Full Text Available Human adipose-derived stem cells are an abundant population of stem cells readily isolated from human adipose tissue that can differentiate into connective tissue lineages including bone, cartilage, fat, and muscle. Activating transcription factor 5 is a transcription factor of the ATF/cAMP response element-binding protein (CREB family. It is transcribed in two types of mRNAs (activating transcription factor 5 isoform 1 and activating transcription factor 5 isoform 2, encoding the same single 30-kDa protein. Although it is well demonstrated that it regulates the proliferation, differentiation, and apoptosis, little is known about its potential role in osteogenic differentiation. The aim of this study was to evaluate the expression levels of the two isoforms and protein during osteogenic differentiation of human adipose-derived stem cells. Our data indicate that activating transcription factor 5 is differentially expressed reaching a peak of expression at the stage of bone mineralization. These findings suggest that activating transcription factor 5 could play an interesting regulatory role during osteogenesis, which would provide a powerful tool to study bone physiology.

Potential Role of Activating Transcription Factor 5 during Osteogenesis.

Science.gov (United States)

Vicari, Luisa; Calabrese, Giovanna; Forte, Stefano; Giuffrida, Raffaella; Colarossi, Cristina; Parrinello, Nunziatina Laura; Memeo, Lorenzo

2016-01-01

Human adipose-derived stem cells are an abundant population of stem cells readily isolated from human adipose tissue that can differentiate into connective tissue lineages including bone, cartilage, fat, and muscle. Activating transcription factor 5 is a transcription factor of the ATF/cAMP response element-binding protein (CREB) family. It is transcribed in two types of mRNAs (activating transcription factor 5 isoform 1 and activating transcription factor 5 isoform 2), encoding the same single 30-kDa protein. Although it is well demonstrated that it regulates the proliferation, differentiation, and apoptosis, little is known about its potential role in osteogenic differentiation. The aim of this study was to evaluate the expression levels of the two isoforms and protein during osteogenic differentiation of human adipose-derived stem cells. Our data indicate that activating transcription factor 5 is differentially expressed reaching a peak of expression at the stage of bone mineralization. These findings suggest that activating transcription factor 5 could play an interesting regulatory role during osteogenesis, which would provide a powerful tool to study bone physiology.

Lipasin, a novel nutritionally-regulated liver-enriched factor that regulates serum triglyceride levels.

Science.gov (United States)

Zhang, Ren

2012-08-10

The metabolic syndrome, a common disorder including glucose intolerance and dyslipidemia, poses a major public health issue. Patients with high blood lipids, such as triglycerides, are at high risk in developing atherosclerotic cardiovascular diseases. To identify genes involved in metabolism, we performed RNA-seq experiments on the liver and fat in mice treated with a high-fat diet or fasting, and identified Gm6484 (named Lipasin) as a novel nutritionally regulated gene. Human LIPASIN is liver specific, while the mouse one is enriched in the liver and fat, including both brown and white adipose tissues. Obesity increases liver Lipasin, whereas fasting reduces its expression in fat. ANGPTL3 (Angiopoietin-like 3) and ANGPTL4 are critical regulators of blood lipids. LIPASIN shares homology with ANGPTL3's N-terminal domain that is needed for lipid regulation, and with ANGPTL4's N-terminal segment that mediates lipoprotein lipase (LPL) binding. Lipasin overexpression by adenoviruses in mice increases serum triglyceride levels, and a recombinant Lipasin inhibits LPL activity. Therefore, a potential mechanism for Lipasin-mediated triglyceride elevation is through reduced triglyceride clearance by LPL inhibition. Lipasin is thus a novel nutritionally-regulated liver-enriched factor that plays a role in lipid metabolism. Copyright © 2012 Elsevier Inc. All rights reserved.

Recent results on cleaning and conditioning the ATF vacuum system

International Nuclear Information System (INIS)

Langley, R.A.; Clark, T.L.; Glowienka, J.C.; Goulding, R.H.; Mioduszewski, P.K.; Rasmussen, D.A.; Rayburn, T.F.; Schaich, C.R.; Shepard, T.D.; Simpkins, J.E.; Yarber, J.L.

1990-01-01

Techniques for cleaning and conditioning the vacuum vessel of the Advanced Toroidal Facility (ATF) and its internal components are described. The vacuum vessel cleaning technique combines baking to 150 degree C and glow discharges with hydrogen gas. Chromium gettering is used to further condition the system. The major internal components are the anodized aluminum baffles in the Thomson scattering system, a graphite-shielded ICRF antenna, two graphite limiters, and a diagnostic graphite plate. Three independent heating systems are used to bake some of the major components of the system. The major characteristics used for assessing cleanliness and conditioning progress are the maximum pressure attained during bakeout, the results of gas analysis, and revelant plasma parameters (e.g., time to radiative decay). Details of the various cleaning and conditioning procedures and results are presented

NR4A orphan nuclear receptor family members, NR4A2 and NR4A3, regulate neutrophil number and survival.

Science.gov (United States)

Prince, Lynne R; Prosseda, Svenja D; Higgins, Kathryn; Carlring, Jennifer; Prestwich, Elizabeth C; Ogryzko, Nikolay V; Rahman, Atiqur; Basran, Alexander; Falciani, Francesco; Taylor, Philip; Renshaw, Stephen A; Whyte, Moira K B; Sabroe, Ian

2017-08-24

The lifespan of neutrophils is plastic and highly responsive to factors that regulate cellular survival. Defects in neutrophil number and survival are common to both hematologic disorders and chronic inflammatory diseases. At sites of inflammation, neutrophils respond to multiple signals that activate protein kinase A (PKA) signaling, which positively regulates neutrophil survival. The aim of this study was to define transcriptional responses to PKA activation and to delineate the roles of these factors in neutrophil function and survival. In human neutrophil gene array studies, we show that PKA activation upregulates a significant number of apoptosis-related genes, the most highly regulated of these being NR4A2 and NR4A3 Direct PKA activation by the site-selective PKA agonist pair N6/8-AHA (8-AHA-cAMP and N6-MB-cAMP) and treatment with endogenous activators of PKA, including adenosine and prostaglandin E2, results in a profound delay of neutrophil apoptosis and concomitant upregulation of NR4A2/3 in a PKA-dependent manner. NR4A3 expression is also increased at sites of neutrophilic inflammation in a human model of intradermal inflammation. PKA activation also promotes survival of murine neutrophil progenitor cells, and small interfering RNA to NR4A2 decreases neutrophil production in this model. Antisense knockdown of NR4A2 and NR4A3 homologs in zebrafish larvae significantly reduces the absolute neutrophil number without affecting cellular migration. In summary, we show that NR4A2 and NR4A3 are components of a downstream transcriptional response to PKA activation in the neutrophil, and that they positively regulate neutrophil survival and homeostasis. © 2017 by The American Society of Hematology.

Beam emittance and the effects of the rf, space charge and wake fields: Application to the ATF photoelectron beam

International Nuclear Information System (INIS)

Parsa, Z.

1991-01-01

Laser driven photoelectron guns are of interest for use in new methods of accelerations, future development of Linear Colliders and new experiments such as Free Electron laser (IFEL). Such guns are potential source of low emittance-high current and short bunch length electron beams, where the emitted electrons are accelerated quickly to a relativistic energy by a strong rf, electric field in the cavity. We present a brief overview of the beam dynamic studies, e.g. emittance for the Brookhaven National Laboratory (BNL) ATF high brightness photocathode radio frequency gun (now in operation), and show the effects of the rf, Space Charge, and Wake fields on the photoelectrons. 4 refs., 7 figs

MicroRNA-10b regulates the renewal of spermatogonial stem cells through Kruppel-like factor 4.

Science.gov (United States)

Li, Jiang; Liu, Xiang; Hu, Xiaopeng; Tian, Geng G; Ma, Wenzhi; Pei, Xiuying; Wang, Yanrong; Wu, Ji

2017-04-01

MicroRNAs (miRs) are functionally important in spermatogenesis, which is the self-renewal or differentiation of spermatogonial stem cells (SSCs). Here, we report a novel role for miR-10b in regulating the self-renewal of mouse SSCs. We showed that miR-10b was highly expressed in mouse SSCs in vitro and enhanced SSC proliferation. Knockdown of miR-10b significantly increased the apoptosis of SSCs compared with controls. Kruppel-like factor 4 was found to be a target gene of miR-10b in the enhancement of SSC proliferation. These findings further our understanding of the self-renewal and differentiation of SSCs and provide a basis for the diagnosis, treatment, and prevention of male infertility. Copyright © 2017 John Wiley & Sons, Ltd.

Nuclear receptor 4a3 (nr4a3 regulates murine mast cell responses and granule content.

Directory of Open Access Journals (Sweden)

Gianni Garcia-Faroldi

Full Text Available Nuclear receptor 4a3 (Nr4a3 is a transcription factor implicated in various settings such as vascular biology and inflammation. We have recently shown that mast cells dramatically upregulate Nuclear receptor 4a3 upon activation, and here we investigated the functional impact of Nuclear receptor 4a3 on mast cell responses. We show that Nuclear receptor 4a3 is involved in the regulation of cytokine/chemokine secretion in mast cells following activation via the high affinity IgE receptor. Moreover, Nuclear receptor 4a3 negatively affects the transcript and protein levels of mast cell tryptase as well as the mast cell's responsiveness to allergen. Together, these findings identify Nuclear receptor 4a3 as a novel regulator of mast cell function.

Complement Factor H-Related Protein 4A Is the Dominant Circulating Splice Variant of CFHR4

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Richard B. Pouw

2018-04-01

Full Text Available Recent research has elucidated circulating levels of almost all factor H-related (FHR proteins. Some of these proteins are hypothesized to act as antagonists of the important complement regulator factor H (FH, fine-tuning complement regulation on human surfaces. For the CFHR4 splice variants FHR-4A and FHR-4B, the individual circulating levels are unknown, with only total levels being described. Specific reagents for FHR-4A or FHR-4B are lacking due to the fact that the unique domains in FHR-4A show high sequence similarity with FHR-4B, making it challenging to distinguish them. We developed an assay that specifically measures FHR-4A using novel, well-characterized monoclonal antibodies (mAbs that target unique domains in FHR-4A only. Using various FHR-4A/FHR-4B-specific mAbs, no FHR-4B was identified in any of the serum samples tested. The results demonstrate that FHR-4A is the dominant splice variant of CFHR4 in the circulation, while casting doubt on the presence of FHR-4B. FHR-4A levels (avg. 2.55 ± 1.46 µg/mL were within the range of most of the previously reported levels for all other FHRs. FHR-4A was found to be highly variable among the population, suggesting a strong genetic regulation. These results shed light on the physiological relevance of the previously proposed role of FHR-4A and FHR-4B as antagonists of FH in the circulation.

Cytokines downregulate the sarcoendoplasmic reticulum pump Ca2+ ATPase 2b and deplete endoplasmic reticulum Ca2+, leading to induction of endoplasmic reticulum stress in pancreatic beta-cells

DEFF Research Database (Denmark)

Cardozo, Alessandra K; Ortis, Fernanda; Storling, Joachim

2005-01-01

-requiring ER-to-nucleus signal kinase 1alpha (IRE1alpha) and PRK (RNA-dependent protein kinase)-like ER kinase (PERK)/activating transcription factor 4 (ATF4), but not ATF6. In contrast, the ER stress-inducing agent thapsigargin triggered these four pathways in parallel. In conclusion, our results suggest...

Autism-Associated Chromatin Regulator Brg1/SmarcA4 Is Required for Synapse Development and Myocyte Enhancer Factor 2-Mediated Synapse Remodeling.

Science.gov (United States)

Zhang, Zilai; Cao, Mou; Chang, Chia-Wei; Wang, Cindy; Shi, Xuanming; Zhan, Xiaoming; Birnbaum, Shari G; Bezprozvanny, Ilya; Huber, Kimberly M; Wu, Jiang I

2016-01-01

Synapse development requires normal neuronal activities and the precise expression of synapse-related genes. Dysregulation of synaptic genes results in neurological diseases such as autism spectrum disorders (ASD). Mutations in genes encoding chromatin-remodeling factor Brg1/SmarcA4 and its associated proteins are the genetic causes of several developmental diseases with neurological defects and autistic symptoms. Recent large-scale genomic studies predicted Brg1/SmarcA4 as one of the key nodes of the ASD gene network. We report that Brg1 deletion in early postnatal hippocampal neurons led to reduced dendritic spine density and maturation and impaired synapse activities. In developing mice, neuronal Brg1 deletion caused severe neurological defects. Gene expression analyses indicated that Brg1 regulates a significant number of genes known to be involved in synapse function and implicated in ASD. We found that Brg1 is required for dendritic spine/synapse elimination mediated by the ASD-associated transcription factor myocyte enhancer factor 2 (MEF2) and that Brg1 regulates the activity-induced expression of a specific subset of genes that overlap significantly with the targets of MEF2. Our analyses showed that Brg1 interacts with MEF2 and that MEF2 is required for Brg1 recruitment to target genes in response to neuron activation. Thus, Brg1 plays important roles in both synapse development/maturation and MEF2-mediated synapse remodeling. Our study reveals specific functions of the epigenetic regulator Brg1 in synapse development and provides insights into its role in neurological diseases such as ASD. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

The Ste20 Family Kinases MAP4K4, MINK1, and TNIK Converge to Regulate Stress-Induced JNK Signaling in Neurons.

Science.gov (United States)

Larhammar, Martin; Huntwork-Rodriguez, Sarah; Rudhard, York; Sengupta-Ghosh, Arundhati; Lewcock, Joseph W

2017-11-15

The c-Jun- N -terminal kinase (JNK) signaling pathway regulates nervous system development, axon regeneration, and neuronal degeneration after acute injury or in chronic neurodegenerative disease. Dual leucine zipper kinase (DLK) is required for stress-induced JNK signaling in neurons, yet the factors that initiate DLK/JNK pathway activity remain poorly defined. In the present study, we identify the Ste20 kinases MAP4K4, misshapen-like kinase 1 (MINK1 or MAP4K6) and TNIK Traf2- and Nck-interacting kinase (TNIK or MAP4K7), as upstream regulators of DLK/JNK signaling in neurons. Using a trophic factor withdrawal-based model of neurodegeneration in both male and female embryonic mouse dorsal root ganglion neurons, we show that MAP4K4, MINK1, and TNIK act redundantly to regulate DLK activation and downstream JNK-dependent phosphorylation of c-Jun in response to stress. Targeting MAP4K4, MINK1, and TNIK, but not any of these kinases individually, is sufficient to protect neurons potently from degeneration. Pharmacological inhibition of MAP4Ks blocks stabilization and phosphorylation of DLK within axons and subsequent retrograde translocation of the JNK signaling complex to the nucleus. These results position MAP4Ks as important regulators of the DLK/JNK signaling pathway. SIGNIFICANCE STATEMENT Neuronal degeneration occurs in disparate circumstances: during development to refine neuronal connections, after injury to clear damaged neurons, or pathologically during disease. The dual leucine zipper kinase (DLK)/c-Jun- N -terminal kinase (JNK) pathway represents a conserved regulator of neuronal injury signaling that drives both neurodegeneration and axon regeneration, yet little is known about the factors that initiate DLK activity. Here, we uncover a novel role for a subfamily of MAP4 kinases consisting of MAP4K4, Traf2- and Nck-interacting kinase (TNIK or MAP4K7), and misshapen-like kinase 1 (MINK1 or MAP4K6) in regulating DLK/JNK signaling in neurons. Inhibition of

Ankaferd Blood Stopper induces apoptosis and regulates PAR1 and ...

African Journals Online (AJOL)

Mine Mumcuoglu

2014-12-16

Dec 16, 2014 ... investigated for its properties. However there are no ... types of proteins and factors acting on cellular functions such as protein-2 (AP2), ... ATF1), cyclic AMP response element binding protein (CREB),. E2F1–5, E2F6, EGR, ...

Experimental Evidence of Edge turbulence driven by multiple mechanisms in ATF

International Nuclear Information System (INIS)

Hidalgo, C.; Harris, J.M.; Uckran, T.; Manson, G.R.; Bell, J.D.

1993-01-01

The scaling properties of edge fluctuations have been investigated using Langmuir probes in the edge region of the Advance Toroidal Facility (ATF). Fluctuations in the ion saturation current (I s /I s ) and transport inferred from the fluctuations increase with increasing density gradient, while keeping unchanged local electron temperature. The modification of the electron temperature in the range (10-50) eV, Keeping constant the density profile, does not have any significant influence on I s /I s . In regions were E r /B∼0, the poloidal phase velocity of the fluctuations is given by V p h∼ 2T e L n B. More then one of any so far proposed mechanisms must be invoked to explain all the experimental observations.(Author)

Opposing roles of STAT4 and Dnmt3a in Th1 gene regulation

Science.gov (United States)

Pham, Duy; Yu, Qing; Walline, Crystal C.; Muthukrishnan, Rajarajeswari; Blum, Janice S.; Kaplan, Mark H.

2013-01-01

The Signal Transducer and Activator of Transcription factor STAT4 is a critical regulator of Th1 differentiation and inflammatory disease. Yet, how STAT4 regulates gene expression is still unclear. In this report, we define a STAT4-dependent sequence of events including H3K4 methylation, Jmjd3 association with STAT4 target loci, and a Jmjd3-dependent decrease in H3K27 trimethylation and DNA methyltransferase (Dnmt) 3a association with STAT4 target loci. Dnmt3a has an obligate role in repressing Th1 gene expression, and in Th1 cultures deficient in both STAT4 and Dnmt3a, there is recovery in the expression of a subset of Th1 genes that is sufficient to increase IFNγ production. Moreover, although STAT4-deficient mice are protected from the development of EAE, mice deficient in STAT4 and conditionally-deficient in Dnmt3a in T cells develop paralysis. Th1 genes that are de-repressed in the absence of Dnmt3a have greater induction following the ectopic expression of the Th1-associated transcription factors T-bet and Hlx1. Together, these data demonstrate that STAT4 and Dnmt3a play opposing roles in regulating Th1 gene expression, and that one mechanism for STAT4-dependent gene programming is in establishing a de-repressed genetic state susceptible to transactivation by additional fate-determining transcription factors. PMID:23772023

27 CFR 4.5 - Related regulations.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Related regulations. 4.5 Section 4.5 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS LABELING AND ADVERTISING OF WINE Scope § 4.5 Related regulations. The following...

Recent results on cleaning and conditioning the ATF vacuum system

International Nuclear Information System (INIS)

Langley, R.A.; Clark, T.L.; Glowienka, J.C.

1989-01-01

Techniques for cleaning and conditioning the vacuum vessel of the Advanced Toroidal Facility (ATF) and its internal components are described. The vacuum vessel cleaning technique combines baking to 150/degree/C and glow discharges with hydrogen gas. Chromium gettering is used to further condition the system. The major internal components are the anodized aluminum baffles in the Thomson scattering system, a graphite-shielded ICRF antenna, two graphite limiters, and a diagnostic graphite plate. Three independent heating systems are used to bake some of the major components of the system. The major characteristics used for assessing cleanliness and conditioning progress are the maximum pressure attained during bakeout, the results of gas analysis, and relevant plasma parameters (e.g., time to radiative decay). Details of the various cleaning and conditioning procedures and results are presented. 5 refs., 8 figs., 3 tabs

Contextual Factors for Establishing Nursing Regulation in Iran: A Qualitative Content Analysis.

Science.gov (United States)

Nejatian, Ahmad; Joulaei, Hassan

2018-04-01

Professional regulation is one of the strategies of the governments which protect the public's right. Nursing practice is not an exception; hence, it is regulated to protect the public against nursing services' adverse effects. Although modern nursing in Iran started from 100 years ago, documents show that there was no regulation mechanism for nursing in Iran till 2016. Hence, this study was conducted to illuminate the contextual factors affecting the nursing regulation process in Iran. To explore the contextual elements of late establishment of nursing registration as an important part of nursing regulation, we applied directed qualitative content analysis. For this purpose, all the historical events and related materials including articles published in scientific journals, gray literature, statements, news articles, and interviews in the period of 2006-2016 were reviewed and analyzed by expert panel and categorized in predetermined groups. Pooled analysis data showed four contributing elements that affected the emerging nursing regulation in Iran. These elements include 1) cultural determinants, 2) structural determinants, 3) situational determinants, and 4) international or exogenous determinants. Nursing regulation is an important health policy issue in Iran which needs to be facilitated by contextual factors. These factors are complicated and country-specific. Political willingness should be accompanied by nursing association willingness to establish and improve nursing regulation. Other researches are recommended to explore actors and process and content of nursing regulation policy in Iran.

A new tomato NAC (NAM/ATAF1/2/CUC2) transcription factor, SlNAC4, functions as a positive regulator of fruit ripening and carotenoid accumulation.

Science.gov (United States)

Zhu, Mingku; Chen, Guoping; Zhou, Shuang; Tu, Yun; Wang, Yi; Dong, Tingting; Hu, Zongli

2014-01-01

Fruit ripening in tomato (Solanum lycopersicum) is a complicated development process affected by both endogenous hormonal and genetic regulators and external signals. Although the role of NOR, a member of the NAC domain family, in mediating tomato fruit ripening has been established, its underlying molecular mechanisms remain unclear. To explore further the role of NAC transcription factors in fruit ripening, we characterized a new tomato NAC domain protein, named SlNAC4, which shows high accumulation in sepal and at the onset of fruit ripening. Various stress treatments including wounding, NaCl, dehydration and low temperature significantly increased the expression of SlNAC4. Reduced expression of SlNAC4 by RNA interference (RNAi) in tomato resulted in delayed fruit ripening, suppressed Chl breakdown and decreased ethylene synthesis mediated mainly through reduced expression of ethylene biosynthesis genes of system-2, and reduced carotenoids by alteration of the carotenoid pathway flux. Transgenic tomato fruits also displayed significant down-regulation of multiple ripening-associated genes, indicating that SlNAC4 functions as a positive regulator of fruit ripening by affecting ethylene synthesis and carotenoid accumulation. Moreover, we also noted that SlNAC4 could not be induced by ethylene and may function upstream of the ripening regulator RIN and positively regulate its expression. Yeast two-hybrid assay further revealed that SlNAC4 could interact with both RIN and NOR protein. These results suggested that ethylene-dependent and -independent processes are regulated by SlNAC4 in the fruit ripening regulatory network.

45 CFR 4.5 - Effect of regulations.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 1 2010-10-01 2010-10-01 false Effect of regulations. 4.5 Section 4.5 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION SERVICE OF PROCESS § 4.5 Effect of regulations. The regulations in this part are intended solely to identify Department officials who are...

Estrogen-related receptor beta interacts with Oct4 to positively regulate Nanog gene expression

NARCIS (Netherlands)

D.L.C. van den Berg (Debbie); W. Zhang (Wensheng); A. Yates (Adam); M.P. Engelen (Erik); K. Takacs (Katalin); K. Bezstarosti (Karel); J.A.A. Demmers (Jeroen); I. Chambers (Ian); R.A. Poor (Raymond)

2008-01-01

textabstractEmbryonic stem (ES) cell self-renewal is regulated by transcription factors, including Oct4, Sox2, and Nanog. A number of additional transcriptional regulators of ES cell self-renewal have recently been identified, including the orphan nuclear receptor estrogen-related receptor beta

The small molecule '1-(4-biphenylylcarbonyl)-4-(5-bromo-2-methoxybenzyl) piperazine oxalate' and its derivatives regulate global protein synthesis by inactivating eukaryotic translation initiation factor 2-alpha.

Science.gov (United States)

Hong, Mi-Na; Nam, Ky-Youb; Kim, Kyung Kon; Kim, So-Young; Kim, InKi

2016-05-01

By environmental stresses, cells can initiate a signaling pathway in which eukaryotic translation initiation factor 2-alpha (eIF2-α) is involved to regulate the response. Phosphorylation of eIF2-α results in the reduction of overall protein neogenesis, which allows cells to conserve resources and to reprogram energy usage for effective stress control. To investigate the role of eIF2-α in cell stress responses, we conducted a viability-based compound screen under endoplasmic reticulum (ER) stress condition, and identified 1-(4-biphenylylcarbonyl)-4-(5-bromo-2-methoxybenzyl) piperazine oxalate (AMC-01) and its derivatives as eIF2-α-inactivating chemical. Molecular characterization of this signaling pathway revealed that AMC-01 induced inactivation of eIF2-α by phosphorylating serine residue 51 in a dose- and time-dependent manner, while the negative control compounds did not affect eIF2-α phosphorylation. In contrast with ER stress induction by thapsigargin, phosphorylation of eIF2-α persisted for the duration of incubation with AMC-01. By pathway analysis, AMC-01 clearly induced the activation of protein kinase RNA-activated (PKR) kinase and nuclear factor-κB (NF-κB), whereas it did not modulate the activity of PERK or heme-regulated inhibitor (HRI). Finally, we could detect a lower protein translation rate in cells incubated with AMC-01, establishing AMC-01 as a potent chemical probe that can regulate eIF2-α activity. We suggest from these data that AMC-01 and its derivative compounds can be used as chemical probes in future studies of the role of eIF2-α in protein synthesis-related cell physiology.

Regulation of Membrane-Type 4 Matrix Metalloproteinase by SLUG Contributes to Hypoxia-Mediated Metastasis

Directory of Open Access Journals (Sweden)

Chi-Hung Huang

2009-12-01

Full Text Available The hypoxic tumor environment has been shown to be critical to cancer metastasis through the promotion of angiogenesis, induction of epithelial-mesenchymal transition (EMT, and acquisition of invasive potential. However, the impact of hypoxia on the expression profile of the proteolytic enzymes involved in invasiveness is relatively unknown. Membrane-type 4 matrix metalloproteinase (MT4-MMP is a glycosyl-phosphatidyl inositol-anchored protease that has been shown to be overexpressed in human cancers. However, detailed mechanisms regarding the regulation and function of MT4-MMP expression in tumor cells remain unknown. Here, we demonstrate that hypoxia or overexpression of hypoxia-inducible factor-1α (HIF-1α induced MT4-MMP expression in human cancer cells. Activation of SLUG, a transcriptional factor regulating the EMT process of human cancers, by HIF-1α was critical for the induction of MT4-MMP under hypoxia. SLUG regulated the transcription of MT4-MMP through direct binding to the E-box located in its proximal promoter. Short-interference RNA-mediated knockdown of MT4-MMP attenuated in vitro invasiveness and in vivo pulmonary colonization of tumor cells without affecting cell migratory ability. MT4-MMP promoted invasiveness and pulmonary colonization through modulation of the expression profile of MMPs and angiogenic factors. Finally, coexpression of HIF-1α and MT4-MMP in human head and neck cancer was predictive of a worse clinical outcome. These findings establish a novel signaling pathway for hypoxia-mediated metastasis and elucidate the underlying regulatory mechanism and functional significance of MT4-MMP in cancer metastasis.

Improving the Organoleptic Properties of a Craft Mezcal Beverage by Increasing Fatty Acid Ethyl Ester Contents through ATF1 Expression in an Engineered Kluyveromyces marxianus UMPe-1 Yeast.

Science.gov (United States)

Campos-García, Jesús; Vargas, Alejandra; Farías-Rosales, Lorena; Miranda, Ana L; Meza-Carmen, Víctor; Díaz-Pérez, Alma L

2018-05-02

Mezcal, a traditional beverage that originated in Mexico, is produced from species of the Agavaceae family. The esters associated with the yeasts utilized during fermentation are important for improving the organoleptic properties of the beverage. We improved the ester contents in a mezcal beverage by using the yeast Kluyveromyces marxianus, which was engineered with the ATF1 gene. ATF1 expression in the recombinant yeast significantly increased compared with that in the parental yeast, but its fermentative parameters were unchanged. Volatile-organic-compound-content analysis showed that esters had significantly increased in the mezcal produced with the engineered yeast. In a sensory-panel test, 48% of the panelists preferred the mezcal produced from the engineered yeast, 30% preferred the mezcal produced from the wild type, and 15 and 7% preferred the two mezcal types produced following the routine procedure. Correlation analysis showed that the fruitiness/sweetness description of the mezcal produced using the ATF1-engineered K. marxianus yeast correlated with the content of the esters, whose presence improved the organoleptic properties of the craft mezcal beverage.

Fatty acid‐binding protein 4 regulates fatty infiltration after rotator cuff tear by hypoxia‐inducible factor 1 in mice

Science.gov (United States)

Lee, Yong‐Soo; Kim, Ja‐Yeon; Oh, Kyung‐Soo

2017-01-01

Abstract Background Fatty infiltration in skeletal muscle is directly linked to loss of muscle strength and is associated with various adverse physical outcomes such as muscle atrophy, inflammation, insulin resistance, mobility impairments, and even mortality in the elderly. Aging, mechanical unloading, muscle injury, and hormonal imbalance are main causes of muscle fat accumulation, and the fat cells are derived from muscle stem cells via adipogenic differentiation. However, the pathogenesis and molecular mechanisms of fatty infiltration in muscles are still not fully defined. Fatty acid‐binding protein 4 (FABP4) is a carrier protein for fatty acids and is involved in fatty acid uptake, transport, and lipid metabolism. Rotator cuff tear (RCT) usually occurs in the elderly and is closely related with fatty infiltration in injured muscle. To investigate potential mechanisms for fatty infiltration other than adipogenic differentiation of muscle stem cells, we examined the role of FABP4 in muscle fatty infiltration in an RCT mouse model. Methods In the RCT model, we evaluated the expression of FABP4 by qRT‐PCR, western blotting, and immunohistochemical analyses. Histological changes such as inflammation and fat accumulation in the injured muscles were examined immunohistochemically. To evaluate whether hypoxia induces FABP4 expression, the levels of FABP4 mRNA and protein in C3H10T1/2 cells after hypoxia were examined. Using a transient transfection assay in 293T cells, we assessed the promoter activity of FABP4 by hypoxia‐inducible factors (HIFs). Additionally, we evaluated the reduction in FABP4 expression and fat accumulation using specific inhibitors for HIF1 and FABP4, respectively. Results FABP4 expression was significantly increased after RCT in mice, and its expression was localized in the intramuscular fatty region. Rotator cuff tear‐induced FABP4 expression was up‐regulated by hypoxia. HIF1α, which is activated by hypoxia, augmented the promoter

Location and repair of air leaks in the ATF vacuum vessel

International Nuclear Information System (INIS)

Schwenterly, S.W.; Gabbard, W.A.; Schaich, C.R.; Yarber, J.L.

1989-01-01

On the basis of partial pressure rate-of-rise and base pressure measurements, it was determined that the Advanced Toroidal Facility (ATF) vacuum vessel had an air leak in the low 10 -4 mbarx ell/s range. Pinpointing this leak by conventional helium leak-checking procedures was not possible, because large portions of the outside of the vessel are covered by the helical field coils and a structural shell. Various alternative leak detection schemes that were considered are summarized and their advantages and disadvantages noted. In the method ultimately employed, gum-rubber patches of various sizes ranging from 12.7 by 12.7 cm to 20.3 by 30.5 cm were positioned on the inside surfaces of the vessel and evacuated by the leak detector (LD). After roughly 5% of the surface was inspected in this way, a leak of >10 -5 mbar xL/s was discovered and localized to an area of 5 by 5 cm. Dye penetrant applied to this area disclosed three pinholes. Two small slag pockets were discovered while these points were being ground out. After these were rewelded, no further leakage could be found in the repaired area. Global leak rates measured after the machine was reevacuated indicated that this leak was about 30% of the overall leak rate. 1 ref., 5 figs., 1 tab

Eukaryotic Initiation Factor 4H Is under Transcriptional Control of p65/NF-κB

Science.gov (United States)

Fiume, Giuseppe; Rossi, Annalisa; de Laurentiis, Annamaria; Falcone, Cristina; Pisano, Antonio; Vecchio, Eleonora; Pontoriero, Marilena; Scala, Iris; Scialdone, Annarita; Masci, Francesca Fasanella; Mimmi, Selena; Palmieri, Camillo; Scala, Giuseppe; Quinto, Ileana

2013-01-01

Protein synthesis is mainly regulated at the initiation step, allowing the fast, reversible and spatial control of gene expression. Initiation of protein synthesis requires at least 13 translation initiation factors to assemble the 80S ribosomal initiation complex. Loss of translation control may result in cell malignant transformation. Here, we asked whether translational initiation factors could be regulated by NF-κB transcription factor, a major regulator of genes involved in cell proliferation, survival, and inflammatory response. We show that the p65 subunit of NF-κB activates the transcription of eIF4H gene, which is the regulatory subunit of eIF4A, the most relevant RNA helicase in translation initiation. The p65-dependent transcriptional activation of eIF4H increased the eIF4H protein content augmenting the rate of global protein synthesis. In this context, our results provide novel insights into protein synthesis regulation in response to NF-κB activation signalling, suggesting a transcription-translation coupled mechanism of control. PMID:23776612

Factor structure of the Self-Regulation Questionnaire (SRQ) at Spanish universities.

Science.gov (United States)

Pichardo, Carmen; Justicia, Fernando; de la Fuente, Jesús; Martínez-Vicente, José Manuel; Berbén, Ana B G

2014-08-04

The Self-Regulation Questionnaire (SRQ) has been used in psychology research during the last decade. The instrument has been used in a variety of life domains: psychological well-being, dispositional happiness, depressive symptoms and career adaptability. This investigation studies the factor structure and internal consistency of the SRQ, extracting a short version in the Spanish context and examining its relation to academic variables (self-regulated learning and grades). The analysis started from a version with 63 items, representing seven conceptual dimensions. This version was administered to a sample of 834 students from Education and Psychology. The data from the above-mentioned sample were randomly divided into two sets, each containing 50% of the students (n = 417): exploratory and confirmatory. In the exploratory sample, exploratory factor analysis findings suggested a more parsimonious measurement model, with 17 items and 4 first-order factors. The confirmatory sample was used in the confirmatory factor analysis. The results show evidence for the internal consistency of the Short Self-Regulation Questionnaire (SSRQ) in the Spanish context, with indices greater than .90 and errors around .05. Regarding academic variables, both versions are related to self-regulated learning (r = .40, p < .01) and students' grades (r = .15, p < .01). Differences from other studies done in North America are discussed, as well as similarities to a study from North-West University (in South Africa).

NapA Mediates a Redox Regulation of the Antioxidant Response, Carbon Utilization and Development in Aspergillus nidulans

Directory of Open Access Journals (Sweden)

Ariann E. Mendoza-Martínez

2017-03-01

Full Text Available The redox-regulated transcription factors (TFs of the bZIP AP1 family, such as yeast Yap1 and fission yeast Pap1, are activated by peroxiredoxin proteins (Prxs to regulate the antioxidant response. Previously, Aspergillus nidulans mutants lacking the Yap1 ortholog NapA have been characterized as sensitive to H2O2 and menadione. Here we study NapA roles in relation to TFs SrrA and AtfA, also involved in oxidant detoxification, showing that these TFs play different roles in oxidative stress resistance, catalase gene regulation and development, during A. nidulans life cycle. We also uncover novel NapA roles in repression of sexual development, normal conidiation, conidial mRNA accumulation, and carbon utilization. The phenotypic characterization of ΔgpxA, ΔtpxA, and ΔtpxB single, double and triple peroxiredoxin mutants in wild type or ΔnapA backgrounds shows that none of these Prxs is required for NapA function in H2O2 and menadione resistance. However, these Prxs participate in a minor NapA-independent H2O2 resistance pathway and NapA and TpxA appear to regulate conidiation along the same route. Using transcriptomic analysis we show that during conidial development NapA-dependent gene expression pattern is different from canonical oxidative stress patterns. In the course of conidiation, NapA is required for regulation of at least 214 genes, including ethanol utilization genes alcR, alcA and aldA, and large sets of genes encoding proteins involved in transcriptional regulation, drug detoxification, carbohydrate utilization and secondary metabolism, comprising multiple oxidoreductases, membrane transporters and hydrolases. In agreement with this, ΔnapA mutants fail to grow or grow very poorly in ethanol, arabinose or fructose as sole carbon sources. Moreover, we show that NapA nuclear localization is induced not only by oxidative stress but also by growth in ethanol and by carbon starvation. Together with our previous work, these results show

Hepatoprotective Effect of Quercetin on Endoplasmic Reticulum Stress and Inflammation after Intense Exercise in Mice through Phosphoinositide 3-Kinase and Nuclear Factor-Kappa B

Directory of Open Access Journals (Sweden)

Yuhan Tang

2016-01-01

Full Text Available The mechanisms underlying intense exercise-induced liver damage and its potential treatments remain unclear. We explored the hepatoprotection and mechanisms of quercetin, a naturally occurring flavonoid, in strenuous exercise-derived endoplasmic reticulum stress (ERS and inflammation. Intense exercise (28 m/min at a 5° slope for 90 min resulted in the leakage of aminotransferases in the BALB/C mice. The hepatic ultrastructural malformations and oxidative stress levels were attenuated by quercetin (100 mg/kg·bw. Intense exercise and thapsigargin- (Tg- induced ERS (glucose-regulated protein 78, GRP78 and inflammatory cytokines levels (IL-6 and TNF-α were decreased with quercetin. Furthermore, quercetin resulted in phosphoinositide 3-kinase (PI3K induction, Ca2+ restoration, and blockade of the activities of Jun N-terminal kinase (JNK, activating transcription factor 6 (ATF6 and especially NF-κB (p65 and p50 nuclear translocation. A PI3K inhibitor abrogated the protection of quercetin on ERS and inflammation of mouse hepatocytes. SP600125 (JNK inhibitor, AEBSF (ATF6 inhibitor, and especially PDTC (NF-κB inhibitor enhanced the quercetin-induced protection against Tg stimulation. Collectively, intense exercise-induced ERS and inflammation were attenuated by quercetin. PI3K/Akt activation and JNK, ATF6, and especially NF-κB suppression were involved in the protection. Our results highlight a novel preventive strategy for treating ERS and inflammation-mediated liver damage induced by intense exercise using natural phytochemicals.

Supra-optimal expression of the cold-regulated OsMyb4 transcription factor in transgenic rice changes the complexity of transcriptional network with major effects on stress tolerance and panicle development

KAUST Repository

Park, Myoungryoul

2010-09-28

The R2R3-type OsMyb4 transcription factor of rice has been shown to play a role in the regulation of osmotic adjustment in heterologous overexpression studies. However, the exact composition and organization of its underlying transcriptional network has not been established to be a robust tool for stress tolerance enhancement by regulon engineering. OsMyb4 network was dissected based on commonalities between the global chilling stress transcriptome and the transcriptome configured by OsMyb4 overexpression. OsMyb4 controls a hierarchical network comprised of several regulatory sub-clusters associated with cellular defense and rescue, metabolism and development. It regulates target genes either directly or indirectly through intermediary MYB, ERF, bZIP, NAC, ARF and CCAAT-HAP transcription factors. Regulatory sub-clusters have different combinations of MYB-like, GCC-box-like, ERD1-box-like, ABRE-like, G-box-like, as1/ocs/TGA-like, AuxRE-like, gibberellic acid response element (GARE)-like and JAre-like cis-elements. Cold-dependent network activity enhanced cellular antioxidant capacity through radical scavenging mechanisms and increased activities of phenylpropanoid and isoprenoid metabolic processes involving various abscisic acid (ABA), jasmonic acid (JA), salicylic acid (SA), ethylene and reactive oxygen species (ROS) responsive genes. OsMyb4 network is independent of drought response element binding protein/C-repeat binding factor (DREB/CBF) and its sub-regulons operate with possible co-regulators including nuclear factor-Y. Because of its upstream position in the network hierarchy, OsMyb4 functions quantitatively and pleiotrophically. Supra-optimal expression causes misexpression of alternative targets with costly trade-offs to panicle development. © 2010 Blackwell Publishing Ltd.

Supra-optimal expression of the cold-regulated OsMyb4 transcription factor in transgenic rice changes the complexity of transcriptional network with major effects on stress tolerance and panicle development.

Science.gov (United States)

Park, Myoung-Ryoul; Yun, Kil-Young; Mohanty, Bijayalaxmi; Herath, Venura; Xu, Fuyu; Wijaya, Edward; Bajic, Vladimir B; Yun, Song-Joong; De Los Reyes, Benildo G

2010-12-01

The R2R3-type OsMyb4 transcription factor of rice has been shown to play a role in the regulation of osmotic adjustment in heterologous overexpression studies. However, the exact composition and organization of its underlying transcriptional network has not been established to be a robust tool for stress tolerance enhancement by regulon engineering. OsMyb4 network was dissected based on commonalities between the global chilling stress transcriptome and the transcriptome configured by OsMyb4 overexpression. OsMyb4 controls a hierarchical network comprised of several regulatory sub-clusters associated with cellular defense and rescue, metabolism and development. It regulates target genes either directly or indirectly through intermediary MYB, ERF, bZIP, NAC, ARF and CCAAT-HAP transcription factors. Regulatory sub-clusters have different combinations of MYB-like, GCC-box-like, ERD1-box-like, ABRE-like, G-box-like, as1/ocs/TGA-like, AuxRE-like, gibberellic acid response element (GARE)-like and JAre-like cis-elements. Cold-dependent network activity enhanced cellular antioxidant capacity through radical scavenging mechanisms and increased activities of phenylpropanoid and isoprenoid metabolic processes involving various abscisic acid (ABA), jasmonic acid (JA), salicylic acid (SA), ethylene and reactive oxygen species (ROS) responsive genes. OsMyb4 network is independent of drought response element binding protein/C-repeat binding factor (DREB/CBF) and its sub-regulons operate with possible co-regulators including nuclear factor-Y. Because of its upstream position in the network hierarchy, OsMyb4 functions quantitatively and pleiotrophically. Supra-optimal expression causes misexpression of alternative targets with costly trade-offs to panicle development. © 2010 Blackwell Publishing Ltd.

SB203580 Modulates p38 MAPK Signaling and Dengue Virus-Induced Liver Injury by Reducing MAPKAPK2, HSP27, and ATF2 Phosphorylation.

Directory of Open Access Journals (Sweden)

Gopinathan Pillai Sreekanth

Full Text Available Dengue virus (DENV infection causes organ injuries, and the liver is one of the most important sites of DENV infection, where viral replication generates a high viral load. The molecular mechanism of DENV-induced liver injury is still under investigation. The mitogen activated protein kinases (MAPKs, including p38 MAPK, have roles in the hepatic cell apoptosis induced by DENV. However, the in vivo role of p38 MAPK in DENV-induced liver injury is not fully understood. In this study, we investigated the role of SB203580, a p38 MAPK inhibitor, in a mouse model of DENV infection. Both the hematological parameters, leucopenia and thrombocytopenia, were improved by SB203580 treatment and liver transaminases and histopathology were also improved. We used a real-time PCR microarray to profile the expression of apoptosis-related genes. Tumor necrosis factor α, caspase 9, caspase 8, and caspase 3 proteins were significantly lower in the SB203580-treated DENV-infected mice than that in the infected control mice. Increased expressions of cytokines including TNF-α, IL-6 and IL-10, and chemokines including RANTES and IP-10 in DENV infection were reduced by SB203580 treatment. DENV infection induced the phosphorylation of p38MAPK, and its downstream signals including MAPKAPK2, HSP27 and ATF-2. SB203580 treatment did not decrease the phosphorylation of p38 MAPK, but it significantly reduced the phosphorylation of MAPKAPK2, HSP27, and ATF2. Therefore, SB203580 modulates the downstream signals to p38 MAPK and reduces DENV-induced liver injury.

Design of the ILC Prototype FONT4 Digital Intra-Train Beam-Based Feedback System

International Nuclear Information System (INIS)

Burrows, P.; Queen Mary, U. of London; Christian, G.B.; Hartin, A.F.; Dabiri Khah, H.; White, G.R.; Oxford U.; Clarke, C.C.; Perry, C.; Oxford Instruments; Kalinin, A.; Daresbury; McCormick, D.J.; Molloy, S.; Ross, M.C.; SLAC

2007-01-01

We present the design of the FONT4 digital intra-train beam position feedback system prototype and preliminary results of initial beam tests at the Accelerator Test Facility (ATF) at KEK. The feedback system incorporates a fast analogue beam position monitor (BPM) front-end signal processor, a digital feedback board, and a kicker driver amplifier. The short bunchtrain, comprising 3 electron bunches separated by c. 150ns, in the ATF extraction line was used to test components of the prototype feedback system

Post-translational regulation of Oct4 transcriptional activity.

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Jonathan P Saxe

Full Text Available Oct4 is a key component of the molecular circuitry which regulates embryonic stem cell proliferation and differentiation. It is essential for maintenance of undifferentiated, pluripotent cell populations, and accomplishes these tasks by binding DNA in multiple heterodimer and homodimer configurations. Very little is known about how formation of these complexes is regulated, or the mechanisms through which Oct4 proteins respond to complex extracellular stimuli which regulate pluripotency. Here, we provide evidence for a phosphorylation-based mechanism which regulates specific Oct4 homodimer conformations. Point mutations of a putative phosphorylation site can specifically abrogate transcriptional activity of a specific homodimer assembly, with little effect on other configurations. Moreover, we performed bioinformatic predictions to identify a subset of Oct4 target genes which may be regulated by this specific assembly, and show that altering Oct4 protein levels affects transcription of Oct4 target genes which are regulated by this assembly but not others. Finally, we identified several signaling pathways which may mediate this phosphorylation and act in combination to regulate Oct4 transcriptional activity and protein stability. These results provide a mechanism for rapid and reversible alteration of Oct4 transactivation potential in response to extracellular signals.

Gene regulation by growth factors

International Nuclear Information System (INIS)

Metz, R.; Gorham, J.; Siegfried, Z.; Leonard, D.; Gizang-Ginsberg, E.; Thompson, M.A.; Lawe, D.; Kouzarides, T.; Vosatka, R.; MacGregor, D.; Jamal, S.; Greenberg, M.E.; Ziff, E.B.

1988-01-01

To coordinate the proliferation and differentiation of diverse cell types, cells of higher eukaryotes communicate through the release of growth factors. These peptides interact with specific transmembrane receptors of other cells and thereby generate intracellular messengers. The many changes in cellular physiology and activity that can be induced by growth factors imply that growth factor-induced signals can reach the nucleus and control gene activity. Moreover, current evidence also suggests that unregulated signaling along such pathways can induce aberrant proliferation and the formation of tumors. This paper reviews investigations of growth factor regulation of gene expression conducted by the authors' laboratory

Capsella rubella TGA4, a bZIP transcription factor, causes delayed flowering in Arabidopsis thaliana

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Li Maofu

2016-01-01

Full Text Available Flowering time is usually regulated by many environmental factors and endogenous signals. TGA family members are bZIP transcription factors that bind to the octopine synthase element, which has been closely linked to defense/stress responses. Most TGA factors interact with non-expressor of PR1 (NPR1 and plant defense responses are strengthened by this interaction. TGA1and TGA4factors bind to NPR1 only in salicylic acid (SA-induced leaves, suggesting that TGA4 has another function during plant development. Here, we isolated a bZIP transcription factor gene, TGA4, from Capsella rubella. TGA4transcripts were detected in most tissues, with high expression in leaves, low expression in stems and flowering buds, and undetectable in siliques. CruTGA4was over expressed in Arabidopsis thaliana wild typeCol-0 plants. Flowering time and total leaf number in the transgenic plants showed that overexpression of CruTGA4could delay flowering in A. thaliana. Our findings suggest that TGA4 may act as flowering regulator that controls plant flowering.

Complex Interdependence Regulates Heterotypic Transcription Factor Distribution and Coordinates Cardiogenesis.

Science.gov (United States)

Luna-Zurita, Luis; Stirnimann, Christian U; Glatt, Sebastian; Kaynak, Bogac L; Thomas, Sean; Baudin, Florence; Samee, Md Abul Hassan; He, Daniel; Small, Eric M; Mileikovsky, Maria; Nagy, Andras; Holloway, Alisha K; Pollard, Katherine S; Müller, Christoph W; Bruneau, Benoit G

2016-02-25

Transcription factors (TFs) are thought to function with partners to achieve specificity and precise quantitative outputs. In the developing heart, heterotypic TF interactions, such as between the T-box TF TBX5 and the homeodomain TF NKX2-5, have been proposed as a mechanism for human congenital heart defects. We report extensive and complex interdependent genomic occupancy of TBX5, NKX2-5, and the zinc finger TF GATA4 coordinately controlling cardiac gene expression, differentiation, and morphogenesis. Interdependent binding serves not only to co-regulate gene expression but also to prevent TFs from distributing to ectopic loci and activate lineage-inappropriate genes. We define preferential motif arrangements for TBX5 and NKX2-5 cooperative binding sites, supported at the atomic level by their co-crystal structure bound to DNA, revealing a direct interaction between the two factors and induced DNA bending. Complex interdependent binding mechanisms reveal tightly regulated TF genomic distribution and define a combinatorial logic for heterotypic TF regulation of differentiation. Copyright © 2016 Elsevier Inc. All rights reserved.

The epigenetic regulation of stem cell factors in hepatic stellate cells.

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Reister, Sven; Kordes, Claus; Sawitza, Iris; Häussinger, Dieter

2011-10-01

The epigenetic regulation by DNA methylation is an important mechanism to control the expression of stem cell factors as demonstrated in tumor cells. It was recently shown that hepatic stellate cells (HSC) express stem/progenitor cell factors and have a differentiation potential. The aim of this work was to investigate if the expression of stem cell markers is regulated by DNA methylation during activation of rat HSC. It was found that CD133, Notch1, and Notch3 are regulated via DNA methylation in HSC, whereas Nestin shows no DNA methylation in HSC and other undifferentiated cells such as embryonic stem cells and umbilical cord blood stem cells from rats. In contrast to this, DNA methylation controls Nestin expression in differentiated cells like hepatocytes and the hepatoma cell line H4IIE. Demethylation by 5-Aza-2-deoxycytidine was sufficient to induce Nestin in H4IIE cells. In quiescent stellate cells and embryonic stem cells, the Nestin expression was suppressed by histone H3 methylation at lysine 9, which is another epigenetic mechanism. Apart from the known induction of Nestin in cultured HSC, this intermediate filament protein was also induced after partial hepatectomy, indicating activation of HSC during liver regeneration. Taken together, this study demonstrates for the first time that the expression of stem cell-associated factors such as CD133, Notch1, and Notch3 is controlled by DNA methylation in HSC. The regulation of Nestin by DNA methylation seems to be restricted to differentiated cells, whereas undifferentiated cells use different epigenetic mechanisms such as histone H3 methylation to control Nestin expression.

SALL4, a stem cell factor, affects the side population by regulation of the ATP-binding cassette drug transport genes.

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Ha-Won Jeong

2011-04-01

Full Text Available Our previous work shows that the stem cell factor SALL4 plays a central role in embryonic and leukemic stem cells. In this study, we report that SALL4 expression was higher in drug resistant primary acute myeloid leukemic patients than those from drug-responsive cases. In addition, while overexpression of SALL4 led to drug resistance in cell lines, cells with decreased SALL4 expression were more sensitive to drug treatments than the parental cells. This led to our investigation of the implication of SALL4 in drug resistance and its role in side population (SP cancer stem cells. SALL4 expression was higher in SP cells compared to non-SP cells by 2-4 fold in various malignant hematopoietic cell lines. Knocking down of SALL4 in isolated SP cells resulted in a reduction of SP cells, indicating that SALL4 is required for their self-renewal. The SP phenotype is known to be mediated by members of the ATP-binding cassette (ABC drug transport protein family, such as ABCG2 and ABCA3. Using chromatin-immunoprecipitation (ChIP, quantitative reverse transcription polymerase chain reaction (qRT-PCR and electrophoretic mobility shift assay(EMSA, we demonstrated that SALL4 was able to bind to the promoter region of ABCA3 and activate its expression while regulating the expression of ABCG2 indirectly. Furthermore, SALL4 expression was positively correlated to those of ABCG2 and ABCA3 in primary leukemic patient samples. Taken together, our results suggest a novel role for SALL4 in drug sensitivity, at least in part through the maintenance of SP cells, and therefore may be responsible for drug-resistance in leukemia. We are the first to demonstrate a direct link between stem cell factor SALL4, SP and drug resistance in leukemia.

34 CFR 461.4 - What regulations apply?

Science.gov (United States)

2010-07-01

... 34 Education 3 2010-07-01 2010-07-01 false What regulations apply? 461.4 Section 461.4 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF VOCATIONAL AND ADULT EDUCATION, DEPARTMENT OF EDUCATION ADULT EDUCATION STATE-ADMINISTERED BASIC GRANT PROGRAM General § 461.4 What...

HOXB4 Gene Expression Is Regulated by CDX2 in Intestinal Epithelial Cells

DEFF Research Database (Denmark)

Jørgensen, Steffen; Coshun, Mehmet; Mikkelsen Homburg, Keld

2016-01-01

analysis and expression data from Caco2 cells also suggests a role for CDX2 in the regulation of HOXB4 gene expression in the intestinal epithelium. Thus, the aim of this study was to investigate whether HOXB4 gene expression is regulated by CDX2 in the intestinal epithelium. We demonstrated binding of CDX......The mammalian Caudal-related homeobox transcription factor 2 (CDX2) plays a key role in the homeobox regulatory network and is essential in regulating the expression of several homeobox (HOX) genes during embryonic development, particularly in the gut. Genome-wide CDX2 chromatin immunoprecipitation......2 to four different CDX2 binding sites in an enhancer region located upstream of the HOXB4 transcription start site. Mutations in the CDX2 binding sites reduced HOXB4 gene activity, and knock down of endogenous CDX2 expression by shRNA reduced HOXB4 gene expression. This is the first report...

Regulation of Membrane-Type 4 Matrix Metalloproteinase by SLUG Contributes to Hypoxia-Mediated Metastasis12

Science.gov (United States)

Huang, Chi-Hung; Yang, Wen-Hao; Chang, Shyue-Yih; Tai, Shyh-Kuan; Tzeng, Cheng-Hwei; Kao, Jung-Yie; Wu, Kou-Juey; Yang, Muh-Hwa

2009-01-01

The hypoxic tumor environment has been shown to be critical to cancer metastasis through the promotion of angiogenesis, induction of epithelial-mesenchymal transition (EMT), and acquisition of invasive potential. However, the impact of hypoxia on the expression profile of the proteolytic enzymes involved in invasiveness is relatively unknown. Membrane-type 4 matrix metalloproteinase (MT4-MMP) is a glycosyl-phosphatidyl inositol-anchored protease that has been shown to be overexpressed in human cancers. However, detailed mechanisms regarding the regulation and function of MT4-MMP expression in tumor cells remain unknown. Here, we demonstrate that hypoxia or overexpression of hypoxia-inducible factor-1α (HIF-1α) induced MT4-MMP expression in human cancer cells. Activation of SLUG, a transcriptional factor regulating the EMT process of human cancers, by HIF-1α was critical for the induction of MT4-MMP under hypoxia. SLUG regulated the transcription of MT4-MMP through direct binding to the E-box located in its proximal promoter. Short-interference RNA-mediated knockdown of MT4-MMP attenuated in vitro invasiveness and in vivo pulmonary colonization of tumor cells without affecting cell migratory ability. MT4-MMP promoted invasiveness and pulmonary colonization through modulation of the expression profile of MMPs and angiogenic factors. Finally, coexpression of HIF-1α and MT4-MMP in human head and neck cancer was predictive of a worse clinical outcome. These findings establish a novel signaling pathway for hypoxia-mediated metastasis and elucidate the underlying regulatory mechanism and functional significance of MT4-MMP in cancer metastasis. PMID:20019845

Combinatorial regulation of tissue specification by GATA and FOG factors

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Chlon, Timothy M.; Crispino, John D.

2012-01-01

The development of complex organisms requires the formation of diverse cell types from common stem and progenitor cells. GATA family transcriptional regulators and their dedicated co-factors, termed Friend of GATA (FOG) proteins, control cell fate and differentiation in multiple tissue types from Drosophila to man. FOGs can both facilitate and antagonize GATA factor transcriptional regulation depending on the factor, cell, and even the specific gene target. In this review, we highlight recent studies that have elucidated mechanisms by which FOGs regulate GATA factor function and discuss how these factors use these diverse modes of gene regulation to control cell lineage specification throughout metazoans. PMID:23048181

Brd4 and HEXIM1: Multiple Roles in P-TEFb Regulation and Cancer

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Ruichuan Chen

2014-01-01

Full Text Available Bromodomain-containing protein 4 (Brd4 and hexamethylene bisacetamide (HMBA inducible protein 1 (HEXIM1 are two opposing regulators of the positive transcription elongation factor b (P-TEFb, which is the master modulator of RNA polymerase II during transcriptional elongation. While Brd4 recruits P-TEFb to promoter-proximal chromatins to activate transcription, HEXIM1 sequesters P-TEFb into an inactive complex containing the 7SK small nuclear RNA. Besides regulating P-TEFb’s transcriptional activity, recent evidence demonstrates that both Brd4 and HEXIM1 also play novel roles in cell cycle progression and tumorigenesis. Here we will discuss the current knowledge on Brd4 and HEXIM1 and their implication as novel therapeutic options against cancer.

Serum levels of RBP4 and adipose tissue levels of PTP1B are increased in obese men resident in northeast Scotland without associated changes in ER stress response genes

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Hoggard N

2012-05-01

Full Text Available Nigel Hoggard1, Abdelali Agouni2, Nimesh Mody2, Mirela Delibegovic21Rowett Institute of Nutrition and Health, 2Integrative Physiology, University of Aberdeen, Aberdeen, UKBackground: Retinol-binding protein 4 (RBP4 is an adipokine identified as a marker of insulin resistance in mice and humans. Protein tyrosine phosphatase 1B (PTP1B expression levels as well as other genes involved in the endoplasmic reticulum (ER stress response are increased in adipose tissue of obese, high-fat-diet-fed mice. In this study we investigated if serum and/or adipose tissue RBP4 protein levels and expression levels of PTP1B and other ER stress-response genes are altered in obese and obese/diabetic men resident in northeast Scotland.Methods: We studied three groups of male volunteers: (1 normal/overweight (body mass index [BMI] < 30, (2 obese (BMI > 30, and (3 obese/diabetic (BMI > 30 controlling their diabetes either by diet or the antidiabetic drug metformin. We analyzed their serum and adipose tissue RBP4 protein levels as well as adipose tissue mRNA expression of PTP1B, binding immunoglobulin protein (BIP, activated transcription factor 4 (ATF4, and glucose-regulated protein 94 (GRP94 alongside other markers of adiposity (percentage body fat, leptin, cholesterol, triglycerides and insulin resistance (oral glucose tolerance tests, insulin, homeostatic model assessment–insulin resistance, C-reactive protein, and adiponectin.Results: We found that obese Scottish subjects had significantly higher serum RBP4 protein levels in comparison to the normal/overweight subjects (P < 0.01. Serum RBP4 levels were normalized in obese/diabetic subjects treated with diet or metformin (P < 0.05. Adipose tissue RBP4 protein levels were comparable between all three groups of subjects as were serum and adipose transthyretin levels. Adipose tissue PTP1B mRNA levels were increased in obese subjects in comparison to normal/overweight subjects (P < 0.05; however diet and/or metformin

Effects of limiter biasing on the ATF torsatron

International Nuclear Information System (INIS)

Uckan, T.; Baylor, L.R.; Bell, J.D.; Bigelow, T.S.; England, A.C.; Harris, J.H.; Isler, R.C.; Jernigan, T.C.; Lyon, J.F.; Ma, C.H.; Mioduszewski, P.K.; Murakami, M.; Rasmussen, D.A.; Wilgen, J.B.; Aceto, S.C.; Zielinski, J.J.

1992-09-01

Positive limiter biasing on the currentless Advanced Toroidal Facility (ATF) torsatron produces a significant increase in the particle confinement with no improvement in the energy confinement. Experiments have been carried out in 1-T plasmas with ∼400 kill of electron cyclotron heating ECM. Two rail limiters located at the last closed flux surface (LCFS), one at the top and one at the bottom of the device, are biased at positive and negative potentials with respect to the vessel. When the limiters are positively biased at up to 300 V, the density increases sharply to the ECH cutoff value. At the same time, the H α radiation drops, indicating that the particle confinement improves. When the density is kept constant, the H α radiation is further reduced and there is almost no change in the plasma stored energy. Under these conditions, the density profile becomes peaked and the electric field becomes outward-pointing outside the LCFS and more negative inside the LCFS. In contrast, negative biasing yields some reduction of the density and stored energy at constant gas feed, and the plasma potential profile remains the same. Biasing has almost no effect on the intrinsic impurity levels in the plasma

Development and quality assessments of commercial heat production of ATF FeCrAl tubes

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, Yukinori [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2015-09-01

Development and quality assessment of the 2^nd generation ATF FeCrAl tube production with commercial manufacturers were conducted. The manufacturing partners include Sophisticated Alloys, Inc. (SAI), Butler, PA for FeCrAl alloy casting via vacuum induction melting, Oak Ridge National Laboratory (ORNL) for extrusion process to prepare the master bars/tubes to be tube-drawn, and Rhenium Alloys, Inc. (RAI), North Ridgeville, OH, for tube-drawing process. The masters bars have also been provided to Los Alamos National Laboratory (LANL) who works with Century Tubes, Inc., (CTI), San Diego, CA, as parallel tube production effort under the current program.

Differential distribution of the Ca (2+) regulator Pcp4 in the branchial arches is regulated by Hoxa2.

Science.gov (United States)

Anderson, Megan; Amin, Shilu; Luise, Fabiana; Zeef, Leo; Bobola, Nicoletta

2013-01-01

Branchial arches are externally visible tissue bands in the head region of all vertebrate embryos. Although initially formed from similar components, each arch will give rise to different head and neck structures. In a screen designed to characterize the molecular control of branchial arch identity in mouse, we identified Pcp4 as a second branchial arch-specific molecular signature. We further show that the transcription factor Hoxa2 binds to Pcp4 chromatin and regulates Pcp4 expression in the second arch. Hoxa2 is also sufficient to induce Pcp4 expression in anterior first arch cells, which are Pcp4-negative.

Obesity challenges the hepatoprotective function of the integrated stress response to asparaginase exposure in mice.

Science.gov (United States)

Nikonorova, Inna A; Al-Baghdadi, Rana J T; Mirek, Emily T; Wang, Yongping; Goudie, Michael P; Wetstein, Berish B; Dixon, Joseph L; Hine, Christopher; Mitchell, James R; Adams, Christopher M; Wek, Ronald C; Anthony, Tracy G

2017-04-21

Obesity increases risk for liver toxicity by the anti-leukemic agent asparaginase, but the mechanism is unknown. Asparaginase activates the integrated stress response (ISR) via sensing amino acid depletion by the eukaryotic initiation factor 2 (eIF2) kinase GCN2. The goal of this work was to discern the impact of obesity, alone versus alongside genetic disruption of the ISR, on mechanisms of liver protection during chronic asparaginase exposure in mice. Following diet-induced obesity, biochemical analysis of livers revealed that asparaginase provoked hepatic steatosis that coincided with activation of another eIF2 kinase PKR-like endoplasmic reticulum kinase (PERK), a major ISR transducer to ER stress. Genetic loss of Gcn2 intensified hepatic PERK activation to asparaginase, yet surprisingly, mRNA levels of key ISR gene targets such as Atf5 and Trib3 failed to increase. Instead, mechanistic target of rapamycin complex 1 (mTORC1) signal transduction was unleashed, and this coincided with liver dysfunction reflected by a failure to maintain hydrogen sulfide production or apolipoprotein B100 (ApoB100) expression. In contrast, obese mice lacking hepatic activating transcription factor 4 ( Atf4 ) showed an exaggerated ISR and greater loss of endogenous hydrogen sulfide but normal inhibition of mTORC1 and maintenance of ApoB100 during asparaginase exposure. In both genetic mouse models, expression and phosphorylation of Sestrin2, an ATF4 gene target, was increased by asparaginase, suggesting mTORC1 inhibition during asparaginase exposure is not driven via eIF2-ATF4-Sestrin2. In conclusion, obesity promotes a maladaptive ISR during asparaginase exposure. GCN2 functions to repress mTORC1 activity and maintain ApoB100 protein levels independently of Atf4 expression, whereas hydrogen sulfide production is promoted via GCN2-ATF4 pathway. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Development of an S-band cavity Beam Position Monitor for ATF2

Science.gov (United States)

Heo, A.; Kim, E.-S.; Kim, H.; Son, D.; Honda, Y.; Tauchi, T.

2013-04-01

We have developed an S-band cavity Beam Position Monitor (BPM) in order to measure the position of an electron beam in the final focus area at ATF2, which is the test facility for the final focus design for the International Linear Collider (ILC). The lattice of the ILC Beam Delivery System (BDS) has been modified, requiring a larger physical aperture of 40 mm in the final focus area. The beam orbit measurement in this area is now covered with high resolution S-Band cavity BPMs. In this paper we summarize the design of the cavity BPM and the first experimental results. The calibration slopes were measured as 0.87 counts/μm in the x-coordinate direction and 1.16 counts/μm in the y-coordinate direction.

ZNF143 protein is an important regulator of the myeloid transcription factor C/EBP

Czech Academy of Sciences Publication Activity Database

Gonzalez, D.; Luyten, A.; Bartholdy, B.; Zhou, Q.; Kardošová, Miroslava; Ebralidze, A.; Swanson, K.D.; Radomska, H.S.; Zhang, P.; Kobayashi, S.S.; Welner, R.S.; Levantini, E.; Steidl, U.; Chong, G.; Collombet, S.; Choi, M.H.; Friedman, A.D.; Scott, L.M.; Alberich-Jorda, Meritxell; Tenen, D.G.

2017-01-01

Roč. 292, č. 46 (2017), s. 18924-18936 ISSN 0021-9258 Institutional support: RVO:68378050 Keywords : CCAAT-enhancer-binding protein * gene regulation * hematopoiesis * promoter * transcription factor * EBPalpha * ZNF143 Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Cell biology Impact factor: 4.125, year: 2016

Histones Induce the Procoagulant Phenotype of Endothelial Cells through Tissue Factor Up-Regulation and Thrombomodulin Down-Regulation.

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Kim, Ji Eun; Yoo, Hyun Ju; Gu, Ja Yoon; Kim, Hyun Kyung

2016-01-01

The high circulating levels of histones found in various thrombotic diseases may compromise the anticoagulant barrier of endothelial cells. We determined how histones affect endothelial procoagulant tissue factor (TF) and anticoagulant thrombomodulin (TM). Surface antigens, soluble forms, and mRNA levels of TF and TM were measured by flow cytometry, ELISA, and real-time RT-PCR, respectively. TF and TM activity were measured using procoagulant activity, thrombin generation, or chromogenic assays. Involvement of the toll-like receptor (TLR) was assessed using the neutralizing antibodies. Histones dose-dependently induced surface antigens, activity and mRNA levels of endothelial TF. Histone-treated endothelial cells significantly shortened the lag time and enhanced the endogenous thrombin potential of normal plasma, which was normalized by a TF neutralizing antibody. Histones induced phosphatidylserine and protein-disulfide isomerase expression in endothelial cells. Histones also reduced the surface antigen, activity, and mRNA levels of endothelial TM. Polysialic acid and heparin reversed the histone-induced TF up-regulation and TM down-regulation. Activated protein C did not affect the TF up-regulation, but interrupted TM down-regulation. TLR2, and TLR4 inhibitors partially blocked the TF up-regulation. Histones induced the endothelial procoagulant phenotype through TF up-regulation and TM down-regulation. The effects of histones were partly mediated by TLR2, TLR4. Strategies to inhibit the harmful effects of histones in endothelial cells may be required in order to prevent a thrombotic environment.

Coagulation factor VII is regulated by androgen receptor in breast cancer.

Science.gov (United States)

Naderi, Ali

2015-02-01

Androgen receptor (AR) is widely expressed in breast cancer; however, there is limited information on the key molecular functions and gene targets of AR in this disease. In this study, gene expression data from a cohort of 52 breast cancer cell lines was analyzed to identify a network of AR co-expressed genes. A total of 300 genes, which were significantly enriched for cell cycle and metabolic functions, showed absolute correlation coefficients (|CC|) of more than 0.5 with AR expression across the dataset. In this network, a subset of 35 "AR-signature" genes were highly co-expressed with AR (|CC|>0.6) that included transcriptional regulators PATZ1, NFATC4, and SPDEF. Furthermore, gene encoding coagulation factor VII (F7) demonstrated the closest expression pattern with AR (CC=0.716) in the dataset and factor VII protein expression was significantly associated to that of AR in a cohort of 209 breast tumors. Moreover, functional studies demonstrated that AR activation results in the induction of factor VII expression at both transcript and protein levels and AR directly binds to a proximal region of F7 promoter in breast cancer cells. Importantly, AR activation in breast cancer cells induced endogenous factor VII activity to convert factor X to Xa in conjunction with tissue factor. In summary, F7 is a novel AR target gene and AR activation regulates the ectopic expression and activity of factor VII in breast cancer cells. These findings have functional implications in the pathobiology of thromboembolic events and regulation of factor VII/tissue factor signaling in breast cancer. Copyright © 2014 Elsevier Inc. All rights reserved.

Telomere-mediated chromosomal instability triggers TLR4 induced inflammation and death in mice.

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Rabindra N Bhattacharjee

Full Text Available BACKGROUND: Telomeres are essential to maintain chromosomal stability. Cells derived from mice lacking telomerase RNA component (mTERC-/- mice display elevated telomere-mediated chromosome instability. Age-dependent telomere shortening and associated chromosome instability reduce the capacity to respond to cellular stress occurring during inflammation and cancer. Inflammation is one of the important risk factors in cancer progression. Controlled innate immune responses mediated by Toll-like receptors (TLR are required for host defense against infection. Our aim was to understand the role of chromosome/genome instability in the initiation and maintenance of inflammation. METHODOLOGY/PRINCIPAL FINDINGS: We examined the function of TLR4 in telomerase deficient mTERC-/- mice harbouring chromosome instability which did not develop any overt immunological disorder in pathogen-free condition or any form of cancers at this stage. Chromosome instability was measured in metaphase spreads prepared from wildtype (mTERC+/+, mTERC+/- and mTERC-/- mouse splenocytes. Peritoneal and/or bone marrow-derived macrophages were used to examine the responses of TLR4 by their ability to produce inflammatory mediators TNFalpha and IL6. Our results demonstrate that TLR4 is highly up-regulated in the immune cells derived from telomerase-null (mTERC-/- mice and lipopolysaccharide, a natural ligand for TLR4 stabilises NF-kappaB binding to its promoter by down-regulating ATF-3 in mTERC-/- macrophages. CONCLUSIONS/SIGNIFICANCE: Our findings implied that background chromosome instability in the cellular level stabilises the action of TLR4-induced NF-kappaB action and sensitises cells to produce excess pro-inflammatory mediators. Chromosome/genomic instability data raises optimism for controlling inflammation by non-toxic TLR antagonists among high-risk groups.

Measurements of the fast ion distribution during neutral beam injection and ion cyclotron heating in ATF [Advanced Toroidal Facility

International Nuclear Information System (INIS)

Wade, M.R.; Kwon, M.; Thomas, C.E.; Colchin, R.J.; England, A.C.; Gossett, J.M.; Horton, L.D.; Isler, R.C.; Lyon, J.F.; Rasmussen, D.A.; Rayburn, T.M.; Shepard, T.D.; Bell, G.L.; Fowler, R.H.; Morris, R.N.

1990-01-01

A neutral particle analyzer (NPA) with horizontal and vertical scanning capability has been used to make initial measurements of the fast ion distribution during neutral beam injection (NBI) and ion cyclotron heating (ICH) on the Advanced Toroidal Facility (ATF). These measurements are presented and compared with the results of modeling codes that predict the analyzer signals during these heating processes. 6 refs., 5 figs

MBTPS2 mutations cause defective regulated intramembrane proteolysis in X-linked osteogenesis imperfecta

Science.gov (United States)

Lindert, Uschi; Cabral, Wayne A.; Ausavarat, Surasawadee; Tongkobpetch, Siraprapa; Ludin, Katja; Barnes, Aileen M.; Yeetong, Patra; Weis, Maryann; Krabichler, Birgit; Srichomthong, Chalurmpon; Makareeva, Elena N.; Janecke, Andreas R.; Leikin, Sergey; Röthlisberger, Benno; Rohrbach, Marianne; Kennerknecht, Ingo; Eyre, David R.; Suphapeetiporn, Kanya; Giunta, Cecilia; Marini, Joan C.; Shotelersuk, Vorasuk

2016-01-01

Osteogenesis imperfecta (OI) is a collagen-related bone dysplasia. We identified an X-linked recessive form of OI caused by defects in MBTPS2, which encodes site-2 metalloprotease (S2P). MBTPS2 missense mutations in two independent kindreds with moderate/severe OI cause substitutions at highly conserved S2P residues. Mutant S2P has normal stability, but impaired functioning in regulated intramembrane proteolysis (RIP) of OASIS, ATF6 and SREBP transcription factors, consistent with decreased proband secretion of type I collagen. Further, hydroxylation of the collagen lysine residue (K87) critical for crosslinking is reduced in proband bone tissue, consistent with decreased lysyl hydroxylase 1 in proband osteoblasts. Reduced collagen crosslinks presumptively undermine bone strength. Also, proband osteoblasts have broadly defective differentiation. These mutations provide evidence that RIP plays a fundamental role in normal bone development. PMID:27380894

Function of the PHA-4/FOXA transcription factor during C. elegans post-embryonic development

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Chen Di

2008-02-01

Full Text Available Abstract Background pha-4 encodes a forkhead box (FOX A transcription factor serving as the C. elegans pharynx organ identity factor during embryogenesis. Using Serial Analysis of Gene Expression (SAGE, comparison of gene expression profiles between growing stages animals and long-lived, developmentally diapaused dauer larvae revealed that pha-4 transcription is increased in the dauer stage. Results Knocking down pha-4 expression by RNAi during post-embryonic development showed that PHA-4 is essential for dauer recovery, gonad and vulva development. daf-16, which encodes a FOXO transcription factor regulated by insulin/IGF-1 signaling, shows overlapping expression patterns and a loss-of-function post-embryonic phenotype similar to that of pha-4 during dauer recovery. pha-4 RNAi and daf-16 mutations have additive effects on dauer recovery, suggesting these two regulators may function in parallel pathways. Gene expression studies using RT-PCR and GFP reporters showed that pha-4 transcription is elevated under starvation, and a conserved forkhead transcription factor binding site in the second intron of pha-4 is important for the neuronal expression. The vulval transcription of lag-2, which encodes a ligand for the LIN-12/Notch lateral signaling pathway, is inhibited by pha-4 RNAi, indicating that LAG-2 functions downstream of PHA-4 in vulva development. Conclusion Analysis of PHA-4 during post-embryonic development revealed previously unsuspected functions for this important transcriptional regulator in dauer recovery, and may help explain the network of transcriptional control integrating organogenesis with the decision between growth and developmental arrest at the dauer entry and exit stages.

Systems Analyses Reveal Shared and Diverse Attributes of Oct4 Regulation in Pluripotent Cells

DEFF Research Database (Denmark)

Ding, Li; Paszkowski-Rogacz, Maciej; Winzi, Maria

2015-01-01

We combine a genome-scale RNAi screen in mouse epiblast stem cells (EpiSCs) with genetic interaction, protein localization, and "protein-level dependency" studies-a systematic technique that uncovers post-transcriptional regulation-to delineate the network of factors that control the expression...... of Oct4, a key regulator of pluripotency. Our data signify that there are similarities, but also fundamental differences in Oct4 regulation in EpiSCs versus embryonic stem cells (ESCs). Through multiparametric data analyses, we predict that Tox4 is associating with the Paf1C complex, which maintains cell...... identity in both cell types, and validate that this protein-protein interaction exists in ESCs and EpiSCs. We also identify numerous knockdowns that increase Oct4 expression in EpiSCs, indicating that, in stark contrast to ESCs, Oct4 is under active repressive control in EpiSCs. These studies provide...

The Regulation of para-Nitrophenol Degradation in Pseudomonas putida DLL-E4.

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Qiongzhen Chen

Full Text Available Pseudomonas putida DLL-E4 can efficiently degrade para-nitrophenol and its intermediate metabolite hydroquinone. The regulation of para-nitrophenol degradation was studied, and PNP induced a global change in the transcriptome of P. putida DLL-E4. When grown on PNP, the wild-type strain exhibited significant downregulation of 2912 genes and upregulation of 845 genes, whereas 2927 genes were downregulated and 891 genes upregulated in a pnpR-deleted strain. Genes related to two non-coding RNAs (ins1 and ins2, para-nitrophenol metabolism, the tricarboxylic acid cycle, the outer membrane porin OprB, glucose dehydrogenase Gcd, and carbon catabolite repression were significantly upregulated when cells were grown on para-nitrophenol plus glucose. pnpA, pnpR, pnpC1C2DECX1X2, and pnpR1 are key genes in para-nitrophenol degradation, whereas pnpAb and pnpC1bC2bDbEbCbX1bX2b have lost the ability to degrade para-nitrophenol. Multiple components including transcriptional regulators and other unknown factors regulate para-nitrophenol degradation, and the transcriptional regulation of para-nitrophenol degradation is complex. Glucose utilization was enhanced at early stages of para-nitrophenol supplementation. However, it was inhibited after the total consumption of para-nitrophenol. The addition of glucose led to a significant enhancement in para-nitrophenol degradation and up-regulation in the expression of genes involved in para-nitrophenol degradation and carbon catabolite repression (CCR. It seemed that para-nitrophenol degradation can be regulated by CCR, and relief of CCR might contribute to enhanced para-nitrophenol degradation. In brief, the regulation of para-nitrophenol degradation seems to be controlled by multiple factors and requires further study.

The Cell Adhesion Molecule Necl-4/CADM4 Serves as a Novel Regulator for Contact Inhibition of Cell Movement and Proliferation.

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Shota Yamana

Full Text Available Contact inhibition of cell movement and proliferation is critical for proper organogenesis and tissue remodeling. We show here a novel regulatory mechanism for this contact inhibition using cultured vascular endothelial cells. When the cells were confluently cultured, Necl-4 was up-regulated and localized at cell-cell contact sites where it cis-interacted with the vascular endothelial growth factor (VEGF receptor. This interaction inhibited the tyrosine-phosphorylation of the VEGF receptor through protein-tyrosine phosphatase, non-receptor type 13 (PTPN13, eventually reducing cell movement and proliferation. When the cells were sparsely cultured, Necl-4 was down-regulated but accumulated at leading edges where it inhibited the activation of Rho-associated protein kinase through PTPN13, eventually facilitating the VEGF-induced activation of Rac1 and enhancing cell movement. Necl-4 further facilitated the activation of extracellular signal-regulated kinase 1/2, eventually enhancing cell proliferation. Thus, Necl-4 serves as a novel regulator for contact inhibition of cell movement and proliferation cooperatively with the VEGF receptor and PTPN13.

12 CFR 1206.4 - Increased costs of regulation.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Increased costs of regulation. 1206.4 Section 1206.4 Banks and Banking FEDERAL HOUSING FINANCE AGENCY ORGANIZATION AND OPERATIONS ASSESSMENTS § 1206... regulation of a Regulated Entity due to its classification as other than adequately capitalized, or as a...

Novel Roles for the Insulin-Regulated Glucose Transporter-4 in Hippocampally Dependent Memory.

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Pearson-Leary, Jiah; McNay, Ewan C

2016-11-23

The insulin-regulated glucose transporter-4 (GluT4) is critical for insulin- and contractile-mediated glucose uptake in skeletal muscle. GluT4 is also expressed in some hippocampal neurons, but its functional role in the brain is unclear. Several established molecular modulators of memory processing regulate hippocampal GluT4 trafficking and hippocampal memory formation is limited by both glucose metabolism and insulin signaling. Therefore, we hypothesized that hippocampal GluT4 might be involved in memory processes. Here, we show that, in male rats, hippocampal GluT4 translocates to the plasma membrane after memory training and that acute, selective intrahippocampal inhibition of GluT4-mediated glucose transport impaired memory acquisition, but not memory retrieval. Other studies have shown that prolonged systemic GluT4 blockade causes insulin resistance. Unexpectedly, we found that prolonged hippocampal blockade of glucose transport through GluT4-upregulated markers of hippocampal insulin signaling prevented task-associated depletion of hippocampal glucose and enhanced both working and short-term memory while also impairing long-term memory. These effects were accompanied by increased expression of hippocampal AMPA GluR1 subunits and the neuronal GluT3, but decreased expression of hippocampal brain-derived neurotrophic factor, consistent with impaired ability to form long-term memories. Our findings are the first to show the cognitive impact of brain GluT4 modulation. They identify GluT4 as a key regulator of hippocampal memory processing and also suggest differential regulation of GluT4 in the hippocampus from that in peripheral tissues. The role of insulin-regulated glucose transporter-4 (GluT4) in the brain is unclear. In the current study, we demonstrate that GluT4 is a critical component of hippocampal memory processes. Memory training increased hippocampal GluT4 translocation and memory acquisition was impaired by GluT4 blockade. Unexpectedly, whereas long

Regulation of the yeast metabolic cycle by transcription factors with periodic activities

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Pellegrini Matteo

2011-10-01

Full Text Available Abstract Background When growing budding yeast under continuous, nutrient-limited conditions, over half of yeast genes exhibit periodic expression patterns. Periodicity can also be observed in respiration, in the timing of cell division, as well as in various metabolite levels. Knowing the transcription factors involved in the yeast metabolic cycle is helpful for determining the cascade of regulatory events that cause these patterns. Results Transcription factor activities were estimated by linear regression using time series and genome-wide transcription factor binding data. Time-translation matrices were estimated using least squares and were used to model the interactions between the most significant transcription factors. The top transcription factors have functions involving respiration, cell cycle events, amino acid metabolism and glycolysis. Key regulators of transitions between phases of the yeast metabolic cycle appear to be Hap1, Hap4, Gcn4, Msn4, Swi6 and Adr1. Conclusions Analysis of the phases at which transcription factor activities peak supports previous findings suggesting that the various cellular functions occur during specific phases of the yeast metabolic cycle.

Power factor regulation for household usage

Science.gov (United States)

Daud, Nik Ghazali Nik; Hashim, Fakroul Ridzuan; Tarmizi, Muhammad Haziq Ahmad

2018-02-01

Power factor regulator technology has recently drawn attention to the consumer and to power generation company in order for consumers to use electricity efficiently. Controlling of power factor for efficient usage can reduce the production of power in fulfilment demands hence reducing the greenhouse effect. This paper presents the design method of power factor controller for household usage. There are several methods to improve the power factor. The power factor controller used by this method is by using capacitors. Total harmonic distortion also has become a major problem for the reliability of the electrical appliances and techniques to control it will be discussed.

Alterations in leukocyte transcriptional control pathway activity associated with major depressive disorder and antidepressant treatment.

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Mellon, S H; Wolkowitz, O M; Schonemann, M D; Epel, E S; Rosser, R; Burke, H B; Mahan, L; Reus, V I; Stamatiou, D; Liew, C-C; Cole, S W

2016-05-24

Major depressive disorder (MDD) is associated with a significantly elevated risk of developing serious medical illnesses such as cardiovascular disease, immune impairments, infection, dementia and premature death. Previous work has demonstrated immune dysregulation in subjects with MDD. Using genome-wide transcriptional profiling and promoter-based bioinformatic strategies, we assessed leukocyte transcription factor (TF) activity in leukocytes from 20 unmedicated MDD subjects versus 20 age-, sex- and ethnicity-matched healthy controls, before initiation of antidepressant therapy, and in 17 of the MDD subjects after 8 weeks of sertraline treatment. In leukocytes from unmedicated MDD subjects, bioinformatic analysis of transcription control pathway activity indicated an increased transcriptional activity of cAMP response element-binding/activating TF (CREB/ATF) and increased activity of TFs associated with cellular responses to oxidative stress (nuclear factor erythroid-derived 2-like 2, NFE2l2 or NRF2). Eight weeks of antidepressant therapy was associated with significant reductions in Hamilton Depression Rating Scale scores and reduced activity of NRF2, but not in CREB/ATF activity. Several other transcriptional regulation pathways, including the glucocorticoid receptor (GR), nuclear factor kappa-B cells (NF-κB), early growth response proteins 1-4 (EGR1-4) and interferon-responsive TFs, showed either no significant differences as a function of disease or treatment, or activities that were opposite to those previously hypothesized to be involved in the etiology of MDD or effective treatment. Our results suggest that CREB/ATF and NRF2 signaling may contribute to MDD by activating immune cell transcriptome dynamics that ultimately influence central nervous system (CNS) motivational and affective processes via circulating mediators.

Neuron-specific specificity protein 4 bigenomically regulates the transcription of all mitochondria- and nucleus-encoded cytochrome c oxidase subunit genes in neurons.

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Johar, Kaid; Priya, Anusha; Dhar, Shilpa; Liu, Qiuli; Wong-Riley, Margaret T T

2013-11-01

Neurons are highly dependent on oxidative metabolism for their energy supply, and cytochrome c oxidase (COX) is a key energy-generating enzyme in the mitochondria. A unique feature of COX is that it is one of only four proteins in mammalian cells that are bigenomically regulated. Of its thirteen subunits, three are encoded in the mitochondrial genome and ten are nuclear-encoded on nine different chromosomes. The mechanism of regulating this multisubunit, bigenomic enzyme poses a distinct challenge. In recent years, we found that nuclear respiratory factors 1 and 2 (NRF-1 and NRF-2) mediate such bigenomic coordination. The latest candidate is the specificity factor (Sp) family of proteins. In N2a cells, we found that Sp1 regulates all 13 COX subunits. However, we discovered recently that in primary neurons, it is Sp4 and not Sp1 that regulates some of the key glutamatergic receptor subunit genes. The question naturally arises as to the role of Sp4 in regulating COX in primary neurons. The present study utilized multiple approaches, including chromatin immunoprecipitation, promoter mutational analysis, knockdown and over-expression of Sp4, as well as functional assays to document that Sp4 indeed functionally regulate all 13 subunits of COX as well as mitochondrial transcription factors A and B. The present study discovered that among the specificity family of transcription factors, it is the less known neuron-specific Sp4 that regulates the expression of all 13 subunits of mitochondrial cytochrome c oxidase (COX) enzyme in primary neurons. Sp4 also regulates the three mitochondrial transcription factors (TFAM, TFB1M, and TFB2M) and a COX assembly protein SURF-1 in primary neurons. © 2013 International Society for Neurochemistry.

The transcription factor Ace2 and its paralog Swi5 regulate ethanol production during static fermentation through their targets Cts1 and Rps4a in Saccharomyces cerevisiae.

Science.gov (United States)

Wu, Yao; Du, Jie; Xu, Guoqiang; Jiang, Linghuo

2016-05-01

Saccharomyces cerevisiae is the most widely used fermentation organism for ethanol production. However, the gene expression regulatory networks behind the ethanol fermentation are still not fully understood. Using a static fermentation model, we examined the ethanol yields on biomass of deletion mutants for 77 yeast genes encoding nonessential transcription factors, and found that deletion mutants for ACE2 and SWI5 showed dramatically increased ethanol yields. Overexpression of ACE2 or SWI5 in wild type cells reduced their ethanol yields. Furthermore, among the 34 target genes regulated by Ace2 and Swi5, deletion of CTS1,RPS4a,SIC1,EGT2,DSE2, or SCP160 led to increased ethanol yields, with the former two showing higher effects. Overexpression of CTS1 or RPS4a in both ace2/ace2 and swi5/swi5 mutants reduced their ethanol yields. In contrast, deletion of MCR1 or HO significantly decreased ethanol yields, with the former one showing the highest effect. Therefore, Ace2 and Swi5 are two negative regulators of ethanol yield during static fermentation of yeast cells, and both CTS1 and RPS4a are major effectors mediating these two transcription factors in regulating ethanol production. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The dipeptidyl peptidase-4 (DPP-4) inhibitor teneligliptin functions as antioxidant on human endothelial cells exposed to chronic hyperglycemia and metabolic high-glucose memory.

Science.gov (United States)

Pujadas, Gemma; De Nigris, Valeria; Prattichizzo, Francesco; La Sala, Lucia; Testa, Roberto; Ceriello, Antonio

2017-06-01

Dipeptidyl peptidase-4 inhibitors are widely used in type 2 diabetes. Endothelium plays a crucial role maintaining vascular integrity and function. Chronic exposure to high glucose drives to endothelial dysfunction generating oxidative stress. Teneligliptin is a novel dipeptidyl peptidase-4 inhibitor with antioxidant properties. This study is aimed to verify a potential protective action of teneligliptin in endothelial cells exposed to high glucose. Human umbilical vein endothelial cells were cultured under normal (5 mmol/L) or high glucose (25 mmol/L) during 21 days, or at high glucose during 14 days followed by 7 days at normal glucose, to reproduce the high-metabolic memory state. During this period, different concentrations of teneligliptin (0.1, 1.0 and 3.0 µmol/L) or sitagliptin (0.5 µmol/L) were added to cells. Ribonucleic acid and protein expression were assessed for antioxidant response, proliferation, apoptosis and endoplasmic reticulum stress markers. Teneligliptin promotes the antioxidant response in human umbilical vein endothelial cells, reducing ROS levels and inducing Nrf2-target genes messenger ribonucleic acid expression. Teneligliptin, but not sitagliptin, reduces the expression of the nicotine amide adenine dinucleotide phosphate oxidase regulatory subunit P22 -phox , however, both blunt the high glucose-induced increase of TXNIP. Teneligliptin improves proliferation rates in human umbilical vein endothelial cells exposed to high glucose, regulating the expression of cell-cycle inhibitors markers (P53, P21 and P27), and reducing proapoptotic genes (BAX and CASP3), while promotes BCL2 expression. Teneligliptin ameliorates high glucose-induced endoplasmic reticulum stress reducing the expression of several markers (BIP, PERK, ATF4, CHOP, IRE1a and ATF6). Teneligliptin has antioxidant properties, ameliorates oxidative stress and apoptotic phenotype and it can overcome the metabolic memory effect, induced by chronic exposure to high

Regulators of Slc4 bicarbonate transporter activity

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Ian M. Thornell

2015-06-01

Full Text Available The Slc4 family of transporters is comprised of anion exchangers (AE1-4, Na-coupled bicarbonate transporters (NCBTs including electrogenic Na/bicarbonate cotransporters (NBCe1 and NBCe2, electroneutral Na/bicarbonate cotransporters (NBCn1 and NBCn2, and the electroneutral Na-driven Cl-bicarbonate exchanger (NDCBE, as well as a borate transporter (BTR1. These transporters regulate intracellular pH (pHi and contribute to steady-state pHi, but are also involved in other physiological processes including CO2 carriage by red blood cells and solute secretion/reabsorption across epithelia. Acid-base transporters function as either acid extruders or acid loaders, with the Slc4 proteins moving HCO3– either into or out of cells. According to results from both molecular and functional studies, multiple Slc4 proteins and/or associated splice variants with similar expected effects on pHi are often found in the same tissue or cell. Such apparent redundancy is likely to be physiologically important. In addition to regulating pHi, a HCO3– transporter contributes to a cell’s ability to fine tune the intracellular regulation of the cotransported/exchanged ion(s (e.g., Na+ or Cl–. In addition, functionally similar transporters or splice variants with different regulatory profiles will optimize pH physiology and solute transport under various conditions or within subcellular domains. Such optimization will depend on activated signaling pathways and transporter expression profiles. In this review, we will summarize and discuss both classical and more recently identified regulators of the Slc4 proteins. Some of these regulators include traditional second messengers, lipids, binding proteins, autoregulatory domains, and less conventional regulators. The material presented will provide insight into the diversity and physiological significance of multiple members within the Slc4 gene family.

Bone Morphogenetic Protein (BMP-4 and BMP-7 regulate differentially Transforming Growth Factor (TGF-β1 in normal human lung fibroblasts (NHLF

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Lloyd Clare M

2010-06-01

Full Text Available Abstract Background Airway remodelling is thought to be under the control of a complex group of molecules belonging to the Transforming Growth Factor (TGF-superfamily. The Bone Morphogenetic Proteins (BMPs belong to this family and have been shown to regulate fibrosis in kidney and liver diseases. However, the role of BMPs in lung remodelling remains unclear. BMPs may regulate tissue remodelling in asthma by controlling TGF-β-induced profibrotic functions in lung fibroblasts. Methods Cell cultures were exposed to TGF-β1 alone or in the presence of BMP-4 or BMP-7; control cultures were exposed to medium only. Cell proliferation was assessed by quantification of the incorporation of [3H]-thymidine. The expression of the mRNA encoding collagen type I and IV, tenascin C and fibronectin in normal human lung fibroblasts (NHLF was determined by real-time quantitative PCR and the main results were confirmed by ELISA. Cell differentiation was determined by the analysis of the expression of α-smooth muscle actin (α-SMA by western blot and immunohistochemistry. The effect on matrix metalloproteinase (MMP activity was assessed by zymography. Results We have demonstrated TGF-β1 induced upregulation of mRNAs encoding the extracellular matrix proteins, tenascin C, fibronectin and collagen type I and IV when compared to unstimulated NHLF, and confirmed these results at the protein level. BMP-4, but not BMP-7, reduced TGF-β1-induced extracellular matrix protein production. TGF-β1 induced an increase in the activity of the pro-form of MMP-2 which was inhibited by BMP-7 but not BMP-4. Both BMP-4 and BMP-7 downregulated TGF-β1-induced MMP-13 release compared to untreated and TGF-β1-treated cells. TGF-β1 also induced a myofibroblast-like transformation which was partially inhibited by BMP-7 but not BMP-4. Conclusions Our study suggests that some regulatory properties of BMP-7 may be tissue or cell type specific and unveil a potential regulatory role for

Gata4 expression in lateral mesoderm is downstream of BMP4 and isactivated directly by Forkhead and GATA transcription factors through adistal enhancer element

Energy Technology Data Exchange (ETDEWEB)

Rojas, Anabel; De Val, Sarah; Heidt, Analeah B.; Xu, Shan-Mei; Bristow, James; Black, Brian L.

2005-05-20

The GATA family of zinc-finger transcription factors plays key roles in the specification and differentiation of multiple cell types during development. GATA4 is an early regulator of gene expression during the development of endoderm and mesoderm, and genetic studies in mice have demonstrated that GATA4 is required for embryonic development.Despite the importance of GATA4 in tissue specification and differentiation, the mechanisms by which Gata4 expression is activated and the transcription factor pathways upstream of GATA4 remain largely undefined. To identify transcriptional regulators of Gata4 in the mouse,we screened conserved noncoding sequences from the mouse Gata4 gene for enhancer activity in transgenic embryos. Here, we define the regulation of a distal enhancer element from Gata4 that is sufficient to direct expression throughout the lateral mesoderm, beginning at 7.5 days of mouse embryonic development. The activity of this enhancer is initially broad but eventually becomes restricted to the mesenchyme surrounding the liver. We demonstrate that the function of this enhancer in transgenic embryos is dependent upon highly conserved Forkhead and GATA transcription factor binding sites, which are bound by FOXF1 and GATA4,respectively. Furthermore, the activity of the Gata4 lateral mesoderm enhancer is attenuated by the BMP antagonist Noggin, and the enhancer is not activated in Bmp4-null embryos. Thus, these studies establish that Gata4 is a direct transcriptional target of Forkhead and GATA transcription factors in the lateral mesoderm, and demonstrate that Gata4lateral mesoderm enhancer activation requires BMP4, supporting a model in which GATA4 serves as a downstream effector of BMP signaling in the lateral mesoderm.

Sox4 mediates Tbx3 transcriptional regulation of the gap junction protein Cx43

NARCIS (Netherlands)

Boogerd, C.J.; Wong, L.Y.; van den Boogaard, M.; Bakker, M.A.J.; Tessadori, F.; Bakkers, J.; 't Hoen, P.A.C.; Moorman, A.F.; Christoffels, V.M.; Barnett, P.

2011-01-01

Tbx3, a T-box transcription factor, regulates key steps in development of the heart and other organ systems. Here, we identify Sox4 as an interacting partner of Tbx3. Pull-down and nuclear retention assays verify this interaction and in situ hybridization reveals Tbx3 and Sox4 to co-localize

RNF11 is a multifunctional modulator of growth factor receptor signalling and transcriptional regulation.

Science.gov (United States)

Azmi, Peter; Seth, Arun

2005-11-01

Our laboratory has found that the 154aa RING finger protein 11 (RNF11), has modular domains and motifs including a RING-H2 finger domain, a PY motif, an ubiquitin interacting motif (UIM), a 14-3-3 binding sequence and an AKT phosphorylation site. RNF11 represents a unique protein with no other known immediate family members yet described. Comparative genetic analysis has shown that RNF11 is highly conserved throughout evolution. This may indicate a conserved and non-redundant role for the RNF11 protein. Molecular binding assays using RNF11 have shown that RNF11 has important roles in growth factor signalling, ubiquitination and transcriptional regulation. RNF11 has been shown to interact with HECT-type E3 ubiquitin ligases Nedd4, AIP4, Smurf1 and Smurf2, as well as with Cullin1, the core protein in the multi-subunit SCF E3 ubiquitin ligase complex. Work done in our laboratory has shown that RNF11 is capable of antagonizing Smurf2-mediated inhibition of TGFbeta signalling. Furthermore, RNF11 is capable of degrading AMSH, a positive regulator of both TGFbeta and EGFR signalling pathways. Recently, we have found that RNF11 can directly enhance TGFbeta signalling through a direct association with Smad4, the common signal transducer and transcription factor in the TGFbeta, BMP, and Activin pathways. Through its association with Smad4 and other transcription factors, RNF11 may have a role in direct transcriptional regulation. Our laboratory and others have found nearly 80 protein interactions for RNF11, placing RNF11 at the cross-roads of cell signalling and transcriptional regulation. RNF11 is highly expressed in breast tumours. Deregulation of RNF11 function may prove to be harmful to patient therapeutic outcomes. RNF11 may therefore provide a novel target for cancer therapeutics. The purpose of this review is to discuss the role of RNF11 in cell signalling and transcription factor modulation with special attention given to the ubiquitin-proteasomal pathway, TGFbeta

78 FR 22773 - Regulation Strengthening Accountability of Attorneys and Non-Attorney Representatives Appearing...

Science.gov (United States)

2013-04-17

..., Firearms and Explosives (ATF). The commenter states that the ATF requires practitioners to satisfy minimum... the right to review and respond to evidence forming the basis of any potential disciplinary action...

Mutation in the factor VII hepatocyte nuclear factor 4α-binding site contributes to factor VII deficiency.

Science.gov (United States)

Zheng, Xing-Wu; Kudaravalli, Rama; Russell, Theresa T; DiMichele, Donna M; Gibb, Constance; Russell, J Eric; Margaritis, Paris; Pollak, Eleanor S

2011-10-01

Severe coagulant factor VII (FVII) deficiency in postpubertal dizygotic twin males results from two point mutations in the FVII gene, a promoter region T→C transition at -60 and a His-to-Arg substitution at amino acid 348; both mutations prevent persistence of plasma functional FVII. This report documents longitudinal laboratory measurements from infancy to adulthood of FVII coagulant activity (FVII:C) in the twin FVII-deficient patients; it also details specific biochemical analyses of the -60 T→C mutation. The results revealed FVII:C levels of less than 1% in infancy that remain severely decreased through puberty and into adulthood. In-vitro analyses utilizing hepatocyte nuclear factor 4α (HNF4α) co-transfection and a chromatin immunoprecipitation assay indicate that the -60 T→C mutation severely diminishes functional interaction between the FVII promoter and transcription factor HNF4α. The importance of interaction between the FVII gene and HNF4α in normal FVII expression provides an in-vivo illustration of the regulated expression of an autosomal gene encoding a coagulation protein. The constancy of FVII:C and peripubertal patient symptomatology reported here illustrates androgen-independent expression in contrast to expression with an analogous mutation in the promoter region of the gene encoding coagulation FIX.

Prevention of Paclitaxel-induced allodynia by Minocycline: Effect on loss of peripheral nerve fibers and infiltration of macrophages in rats

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Xin Wen-Jun

2010-11-01

Full Text Available Abstract Background Although paclitaxel is a frontline antineoplastic agent for treatment of solid tumors, the paclitaxel-evoked pain syndrome is a serious problem for patients. There is currently no valid drug to prevent or treat the paclitaxel-induced allodynia, partly due to lack of understanding regarding the cellular mechanism. Studies have shown that minocycline, an inhibitor of microglia/macrophage, prevented neuropathic pain and promoted neuronal survival in animal models of neurodegenerative disease. Recently, Cata et al also reported that minocycline inhibited allodynia induced by low-dose paclitaxel (2 mg/kg in rats, but the mechanism is still unclear. Results Here, we investigate by immunohistochemistry the change of intraepidermal nerve fiber (IENF in the hind paw glabrous skin, expression of macrophage and activating transcription factor 3 (ATF3 in DRG at different time points after moderate-dose paclitaxel treatment (cumulative dose 24 mg/kg; 3 × 8 mg/kg in rats. Moreover, we observe the effect of minocycline on the IENF, macrophages and ATF3. The results showed that moderate-dose paclitaxel induced a persisted, gradual mechanical allodynia, which was accompanied by the loss of IENF in the hind paw glabrous skin and up-regulation of macrophages and ATF3 in DRG in rats. The expressions of ATF3 mainly focus on the NF200-positive cells. More importantly, we observed that pretreatment of minocycline at dose of 30 mg/kg or 50 mg/kg, but not 5 mg/kg, prevented paclitaxel-evoked allodynia. The evidence from immunohistochemistry showed that 30 mg/kg minocycline rescued the degeneration of IENF, attenuated infiltration of macrophages and up-regulation of ATF3 induced by paclitaxel treatment in rats. Conclusions Minocycline prevents paclitaxel-evoked allodynia, likely due to its inhibition on loss of IENF, infiltration of macrophages and up-regulation of ATF3 in rats. The finding might provide potential target for preventing paclitaxel

Fgf9 and Wnt4 act as antagonistic signals to regulate mammalian sex determination.

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Yuna Kim

2006-06-01

Full Text Available The genes encoding members of the wingless-related MMTV integration site (WNT and fibroblast growth factor (FGF families coordinate growth, morphogenesis, and differentiation in many fields of cells during development. In the mouse, Fgf9 and Wnt4 are expressed in gonads of both sexes prior to sex determination. Loss of Fgf9 leads to XY sex reversal, whereas loss of Wnt4 results in partial testis development in XX gonads. However, the relationship between these signals and the male sex-determining gene, Sry, was unknown. We show through gain- and loss-of-function experiments that fibroblast growth factor 9 (FGF9 and WNT4 act as opposing signals to regulate sex determination. In the mouse XY gonad, Sry normally initiates a feed-forward loop between Sox9 and Fgf9, which up-regulates Fgf9 and represses Wnt4 to establish the testis pathway. Surprisingly, loss of Wnt4 in XX gonads is sufficient to up-regulate Fgf9 and Sox9 in the absence of Sry. These data suggest that the fate of the gonad is controlled by antagonism between Fgf9 and Wnt4. The role of the male sex-determining switch--Sry in the case of mammals--is to tip the balance between these underlying patterning signals. In principle, sex determination in other vertebrates may operate through any switch that introduces an imbalance between these two signaling pathways.

Development of Electrical Capacitance Sensors for Accident Tolerant Fuel (ATF) Testing at the Transient Reactor Test (TREAT) Facility

Energy Technology Data Exchange (ETDEWEB)

Liu, Maolong; Ryals, Matthew; Ali, Amir; Blandford, Edward; Jensen, Colby; Condie, Keith; Svoboda, John; O' Brien, Robert

2016-08-01

A variety of instruments are being developed and qualified to support the Accident Tolerant Fuels (ATF) program and future transient irradiations at the Transient Reactor Test (TREAT) facility at Idaho National Laboratory (INL). The University of New Mexico (UNM) is working with INL to develop capacitance-based void sensors for determining the timing of critical boiling phenomena in static capsule fuel testing and the volume-averaged void fraction in flow-boiling in-pile water loop fuel testing. The static capsule sensor developed at INL is a plate-type configuration, while UNM is utilizing a ring-type capacitance sensor. Each sensor design has been theoretically and experimentally investigated at INL and UNM. Experiments are being performed at INL in an autoclave to investigate the performance of these sensors under representative Pressurized Water Reactor (PWR) conditions in a static capsule. Experiments have been performed at UNM using air-water two-phase flow to determine the sensitivity and time response of the capacitance sensor under a flow boiling configuration. Initial measurements from the capacitance sensor have demonstrated the validity of the concept to enable real-time measurement of void fraction. The next steps include designing the cabling interface with the flow loop at UNM for Reactivity Initiated Accident (RIA) ATF testing at TREAT and further characterization of the measurement response for each sensor under varying conditions by experiments and modeling.

Adenovirus Protein E4-ORF1 activation of PI3 kinase reveals differential regulation of downstream effector pathways in adipocytes

OpenAIRE

Chaudhary, Natasha; Gonzalez, Eva; Chang, Sung-Hee; Geng, Fuqiang; Rafii, Shahin; Altorki, Nasser K.; McGraw, Timothy E.

2016-01-01

Insulin activation of phosphatidylinositol 3-kinase (PI3K) regulates metabolism, including the translocation of the Glut4 glucose transporter to the plasma membrane and inactivation of the FoxO1 transcription factor. Adenoviral protein E4-ORF1 stimulates cellular glucose metabolism by mimicking growth-factor activation of PI3K. We have used E4-ORF1 as a tool to dissect PI3K-mediated signaling in adipocytes. E4-ORF1 activation of PI3K in adipocytes recapitulates insulin regulation of FoxO1 but...

Psychological Stress, Cocaine and Natural Reward Each Induce Endoplasmic Reticulum Stress Genes in Rat Brain

OpenAIRE

Pavlovsky, Ashly A.; Boehning, Darren; Li, Dingge; Zhang, Yafang; Fan, Xiuzhen; Green, Thomas A.

2013-01-01

Our prior research has shown that the transcription of endoplasmic reticulum (ER) stress transcription factors Activating Transcription Factor 3 (ATF3) and ATF4 are induced by amphetamine and restraint stress in rat striatum. However, presently it is unknown the full extent of ER stress responses to psychological stress or cocaine, and which of the three ER stress pathways is activated. The current study examines transcriptional responses of key ER stress target genes subsequent to psychologi...

The transcription factor KLF2 restrains CD4⁺ T follicular helper cell differentiation.

Science.gov (United States)

Lee, June-Yong; Skon, Cara N; Lee, You Jeong; Oh, Soohwan; Taylor, Justin J; Malhotra, Deepali; Jenkins, Marc K; Rosenfeld, M Geoffrey; Hogquist, Kristin A; Jameson, Stephen C

2015-02-17

T follicular helper (Tfh) cells are essential for efficient B cell responses, yet the factors that regulate differentiation of this CD4(+) T cell subset are incompletely understood. Here we found that the KLF2 transcription factor serves to restrain Tfh cell generation. Induced KLF2 deficiency in activated CD4(+) T cells led to increased Tfh cell generation and B cell priming, whereas KLF2 overexpression prevented Tfh cell production. KLF2 promotes expression of the trafficking receptor S1PR1, and S1PR1 downregulation is essential for efficient Tfh cell production. However, KLF2 also induced expression of the transcription factor Blimp-1, which repressed transcription factor Bcl-6 and thereby impaired Tfh cell differentiation. Furthermore, KLF2 induced expression of the transcription factors T-bet and GATA3 and enhanced Th1 differentiation. Hence, our data indicate KLF2 is pivotal for coordinating CD4(+) T cell differentiation through two distinct and complementary mechanisms: via control of T cell localization and by regulation of lineage-defining transcription factors. Copyright © 2015 Elsevier Inc. All rights reserved.

Regulation of Saccharomyces cerevisiae genetic engineering on the production of acetate esters and higher alcohols during Chinese Baijiu fermentation.

Science.gov (United States)

Li, Wei; Wang, Jian-Hui; Zhang, Cui-Ying; Ma, Hong-Xia; Xiao, Dong-Guang

2017-06-01

Acetate esters and higher alcohols greatly influence the quality and flavor profiles of Chinese Baijiu (Chinese liquor). Various mutants have been constructed to investigate the interactions of ATF1 overexpression, IAH1 deletion, and BAT2 deletion on the production of acetate esters and higher alcohols. The results showed that the overexpression of ATF1 under the control of the PGK1 promoter with BAT2 and IAH1 double-gene deletion led to a higher production of acetate esters and a lower production of higher alcohols than the overexpression of ATF1 with IAH1 deletion or overexpression of ATF1 with BAT2 deletion. Moreover, deletion of IAH1 in ATF1 overexpression strains effectively increased the production of isobutyl acetate and isoamyl acetate by reducing the hydrolysis of acetate esters. The decline in the production of higher alcohol by the ATF1 overexpression strains with BAT2 deletion is due to the interaction of ATF1 overexpression and BAT2 deletion. Mutants with varying abilities of producing acetate esters and higher alcohols were developed by genetic engineering. These strains have great potential for industrial application.

Macrophage activation and differentiation signals regulate schlafen-4 gene expression: evidence for Schlafen-4 as a modulator of myelopoiesis.

Directory of Open Access Journals (Sweden)

Wendy J van Zuylen

Full Text Available BACKGROUND: The ten mouse and six human members of the Schlafen (Slfn gene family all contain an AAA domain. Little is known of their function, but previous studies suggest roles in immune cell development. In this report, we assessed Slfn regulation and function in macrophages, which are key cellular regulators of innate immunity. METHODOLOGY/PRINCIPAL FINDINGS: Multiple members of the Slfn family were up-regulated in mouse bone marrow-derived macrophages (BMM by the Toll-like Receptor (TLR4 agonist lipopolysaccharide (LPS, the TLR3 agonist Poly(I∶C, and in disease-affected joints in the collagen-induced model of rheumatoid arthritis. Of these, the most inducible was Slfn4. TLR agonists that signal exclusively through the MyD88 adaptor protein had more modest effects on Slfn4 mRNA levels, thus implicating MyD88-independent signalling and autocrine interferon (IFN-β in inducible expression. This was supported by the substantial reduction in basal and LPS-induced Slfn4 mRNA expression in IFNAR-1⁻/⁻ BMM. LPS causes growth arrest in macrophages, and other Slfn family genes have been implicated in growth control. Slfn4 mRNA levels were repressed during macrophage colony-stimulating factor (CSF-1-mediated differentiation of bone marrow progenitors into BMM. To determine the role of Slfn4 in vivo, we over-expressed the gene specifically in macrophages in mice using a csf1r promoter-driven binary expression system. Transgenic over-expression of Slfn4 in myeloid cells did not alter macrophage colony formation or proliferation in vitro. Monocyte numbers, as well as inflammatory macrophages recruited to the peritoneal cavity, were reduced in transgenic mice that specifically over-expressed Slfn4, while macrophage numbers and hematopoietic activity were increased in the livers and spleens. CONCLUSIONS: Slfn4 mRNA levels were up-regulated during macrophage activation but down-regulated during differentiation. Constitutive Slfn4 expression in the

Hydrogen peroxide sensing, signaling and regulation of transcription factors

Directory of Open Access Journals (Sweden)

H. Susana Marinho

2014-01-01

Full Text Available The regulatory mechanisms by which hydrogen peroxide (H2O2 modulates the activity of transcription factors in bacteria (OxyR and PerR, lower eukaryotes (Yap1, Maf1, Hsf1 and Msn2/4 and mammalian cells (AP-1, NRF2, CREB, HSF1, HIF-1, TP53, NF-κB, NOTCH, SP1 and SCREB-1 are reviewed. The complexity of regulatory networks increases throughout the phylogenetic tree, reaching a high level of complexity in mammalians. Multiple H2O2 sensors and pathways are triggered converging in the regulation of transcription factors at several levels: (1 synthesis of the transcription factor by upregulating transcription or increasing both mRNA stability and translation; (ii stability of the transcription factor by decreasing its association with the ubiquitin E3 ligase complex or by inhibiting this complex; (iii cytoplasm–nuclear traffic by exposing/masking nuclear localization signals, or by releasing the transcription factor from partners or from membrane anchors; and (iv DNA binding and nuclear transactivation by modulating transcription factor affinity towards DNA, co-activators or repressors, and by targeting specific regions of chromatin to activate individual genes. We also discuss how H2O2 biological specificity results from diverse thiol protein sensors, with different reactivity of their sulfhydryl groups towards H2O2, being activated by different concentrations and times of exposure to H2O2. The specific regulation of local H2O2 concentrations is also crucial and results from H2O2 localized production and removal controlled by signals. Finally, we formulate equations to extract from typical experiments quantitative data concerning H2O2 reactivity with sensor molecules. Rate constants of 140 M−1 s−1 and ≥1.3 × 103 M−1 s−1 were estimated, respectively, for the reaction of H2O2 with KEAP1 and with an unknown target that mediates NRF2 protein synthesis. In conclusion, the multitude of H2O2 targets and mechanisms provides an opportunity for

[Molecular mechanism of Bupleuri Radix and Scutellariae Radix drug pair for depression based on integrative pharmacology platform of traditional Chinese medicine].

Science.gov (United States)

Wang, Jian-Ting; Wang, Shang; Liu, Song-Lin; Wang, Yan-Chun; Li, Jia-Geng; Chen, Yu

2018-04-01

Xiaochaihu decoction is a classic prescription of traditional Chinese medicine. Modern research has proved its anti-depression effect. However, its pharmacological mechanism for anti-depression effect is difficult to be unveiled because of the complexity of compound Chinese medicines. Bupleuri Radix and Scutellariae Radix is the core drug pair of Xiaochaihu decoction. In this research, Bupleuri Radix and Scutellariae Radix were analyzed by the integrative pharmacology platform to study its molecular mechanism for anti-depression. One hundred and sixteen active ingredients were predicted, 62 for Bupleuri Radix, mainly including saikosaponins, acids, alcohols, and 54 for Scutellariae Radix, mainly including flavonoids and glycosides. Its anti-depression effect was relevant to 118 core targets, including 22 known disease targets, such as serotonin receptor(HTR2C), activating transcription factor(ATF1, ATF2), δ opioid receptor(OPRD1), μ opioid receptor (OPRM1), κ opioid receptor(OPRK1), inositol monophosphatase(IMPA1), Toll-like receptor 4 (TLR4), histamine H1 receptor(HRH1), neurotrophic factor tyrosine kinase receptor1 (NTRK1), Glycogen synthetase kinase 3β(GSK3β), etc. The antidepressant effect involved positive regulation of transcription from RNA polymerase Ⅱ promoter, transcription factor binding, cytosol, transcriptional regulation of DNA template, enzyme binding, endocrine system, nervous system, neurotrophin signaling pathway, cell growth and death, signal transduction, thyroid hormone signaling pathway and other related biological processes and metabolic pathways. This study provides a scientific evidence for further study of the anti-depression mechanism of this drug pair. Copyright© by the Chinese Pharmaceutical Association.

Taurine Pretreatment Prevents Isoflurane-Induced Cognitive Impairment by Inhibiting ER Stress-Mediated Activation of Apoptosis Pathways in the Hippocampus in Aged Rats.

Science.gov (United States)

Zhang, Yanan; Li, Dongliang; Li, Haiou; Hou, Dailiang; Hou, Jingdong

2016-10-01

Isoflurane, a commonly used inhalation anesthetic, may induce neurocognitive deficits, especially in elderly patients after surgery. Recent study demonstrated that isoflurane caused endoplasmic reticulum (ER) stress and subsequent neuronal apoptosis in the brain, contributing to cognitive deficits. Taurine, a major intracellular free amino acid, has been shown to inhibit ER stress and neuronal apoptosis in several neurological disorders. Here, we examined whether taurine can prevent isoflurane-induced ER stress and cognitive impairment in aged rats. Thirty minutes prior to a 4-h 1.3 % isoflurane exposure, aged rats were treated with vehicle or taurine at low, middle and high doses. Aged rats without any treatment served as control. The brains were harvested 6 h after isoflurane exposure for molecular measurements, and behavioral study was performed 2 weeks later. Compared with control, isoflurane increased expression of hippocampal ER stress biomarkers including glucose-regulated protein 78, phosphorylated (P-) inositol-requiring enzyme 1, P-eukaryotic initiation factor 2-α (EIF2α), activating transcription factor 4 (ATF-4), cleaved ATF-6 and C/EBP homologous protein, along with activation of apoptosis pathways as indicated by decreased B cell lymphoma 2 (BCL-2)/BCL2-associated X protein, increased expressions of cytochrome-c and cleaved caspase-3. Taurine pretreatment dose-dependently inhibited isoflurane-induced increase in expression of ER stress biomarkers except for P-EIF2α and ATF-4, and reversed isoflurane-induced changes in apoptosis-related proteins. Moreover, isoflurane caused spatial working memory deficits in aged rats, which were prevented by taurine pretreatment. The results indicate that taurine pretreatment prevents anesthetic isoflurane-induced cognitive impairment by inhibiting ER stress-mediated activation of apoptosis pathways in the hippocampus in aged rats.

Brain-derived neurotrophic factor in human subjects with function-altering melanocortin-4 receptor variants

Science.gov (United States)

In rodents, hypothalamic brain-derived neurotrophic factor (BDNF) expression appears to be regulated by melanocortin-4 receptor (MC4R) activity. The impact of MC4R genetic variation on circulating BDNF in humans is unknown. The objective of this study is to compare BDNF concentrations of subjects wi...

TGF-β signaling directly regulates transcription and functional expression of the electrogenic sodium bicarbonate cotransporter 1, NBCe1 (SLC4A4), via Smad4 in mouse astrocytes.

Science.gov (United States)

Khakipoor, Shokoufeh; Ophoven, Christian; Schrödl-Häußel, Magdalena; Feuerstein, Melanie; Heimrich, Bernd; Deitmer, Joachim W; Roussa, Eleni

2017-08-01

The electrogenic sodium bicarbonate cotransporter NBCe1 (SLC4A4) expressed in astrocytes regulates intracellular and extracellular pH. Here, we introduce transforming growth factor beta (TGF-β) as a novel regulator of NBCe1 transcription and functional expression. Using hippocampal slices and primary hippocampal and cortical astrocyte cultures, we investigated regulation of NBCe1 and elucidated the underlying signaling pathways by RT-PCR, immunoblotting, immunofluorescence, intracellular H( + ) recording using the H( + ) -sensitive dye 2',7'-bis-(carboxyethyl)-5-(and-6)-carboxyfluorescein, mink lung epithelial cell (MLEC) assay, and chromatin immunoprecipitation. Activation of TGF-β signaling significantly upregulated transcript, protein, and surface expression of NBCe1. These effects were TGF-β receptor-mediated and suppressed following inhibition of JNK and Smad signaling. Moreover, 4-aminopyridine (4AP)-dependent NBCe1 regulation requires TGF-β. TGF-β increased the rate and amplitude of intracellular H + changes upon challenging NBCe1 in wild-type astrocytes but not in cortical astrocytes from Slc4a4-deficient mice. A Smad4 binding sequence was identified in the NBCe1 promoter and Smad4 binding increased after activation of TGF-β signaling. The data show for the first time that NBCe1 is a direct target of TGF-β/Smad4 signaling. Through activation of the canonical pathway TGF-β acts directly on NBCe1 by binding of Smad4 to the NBCe1 promoter and regulating its transcription, followed by increased protein expression and transport activity. © 2017 The Authors GLIA Published by Wiley Periodicals, Inc.

Exogenous FABP4 induces endoplasmic reticulum stress in HepG2 liver cells.

Science.gov (United States)

Bosquet, Alba; Guaita-Esteruelas, Sandra; Saavedra, Paula; Rodríguez-Calvo, Ricardo; Heras, Mercedes; Girona, Josefa; Masana, Lluís

2016-06-01

Fatty acid binding protein 4 (FABP4) is an intracellular fatty acid (FA) carrier protein that is, in part, secreted into circulation. Circulating FABP4 levels are increased in obesity, diabetes and other insulin resistance (IR) diseases. FAs contribute to IR by promoting endoplasmic reticulum stress (ER stress) and altering the insulin signaling pathway. The effect of FABP4 on ER stress in the liver is not known. The aim of this study was to investigate whether exogenous FABP4 (eFABP4) is involved in the lipid-induced ER stress in the liver. HepG2 cells were cultured with eFABP4 (40 ng/ml) with or without linoleic acid (LA, 200 μM) for 18 h. The expression of ER stress-related markers was determined by Western blotting (ATF6, EIF2α, IRE1 and ubiquitin) and real-time PCR (ATF6, CHOP, EIF2α and IRE1). Apoptosis was studied by flow cytometry using Annexin V-FITC and propidium iodide staining. eFABP4 increased the ER stress markers ATF6 and IRE1 in HepG2 cells. This effect led to insulin resistance mediated by changes in AKT and JNK phosphorylation. Furthermore, eFABP4 significantly induced both apoptosis, as assessed by flow cytometry, and CHOP expression, without affecting necrosis and ubiquitination. The presence of LA increased the ER stress response induced by eFABP4. eFABP4, per se, induces ER stress and potentiates the effect of LA in HepG2 cells, suggesting that FABP4 could be a link between obesity-associated metabolic abnormalities and hepatic IR mechanisms. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Modifying chemotherapy response by targeted inhibition of eukaryotic initiation factor 4A

International Nuclear Information System (INIS)

Cencic, R; Robert, F; Galicia-Vázquez, G; Malina, A; Ravindar, K; Somaiah, R; Pierre, P; Tanaka, J; Deslongchamps, P; Pelletier, J

2013-01-01

Translation is regulated predominantly at the initiation phase by several signal transduction pathways that are often usurped in human cancers, including the PI3K/Akt/mTOR axis. mTOR exerts unique administration over translation by regulating assembly of eukaryotic initiation factor (eIF) 4F, a heterotrimeric complex responsible for recruiting 40S ribosomes (and associated factors) to mRNA 5′ cap structures. Hence, there is much interest in targeted therapies that block eIF4F activity to assess the consequences on tumor cell growth and chemotherapy response. We report here that hippuristanol (Hipp), a translation initiation inhibitor that selectively inhibits the eIF4F RNA helicase subunit, eIF4A, resensitizes Eμ-Myc lymphomas to DNA damaging agents, including those that overexpress eIF4E—a modifier of rapamycin responsiveness. As Mcl-1 levels are significantly affected by Hipp, combining its use with the Bcl-2 family inhibitor, ABT-737, leads to a potent synergistic response in triggering cell death in mouse and human lymphoma and leukemia cells. Suppression of eIF4AI using RNA interference also synergized with ABT-737 in murine lymphomas, highlighting eIF4AI as a therapeutic target for modulating tumor cell response to chemotherapy

Comparison of ATF and TJ-II stellarator equilibria as computed by the 3-D VMEC and PIES codes

International Nuclear Information System (INIS)

Johnson, J.L.; Monticello, D.A.; Reiman, A.H.; Hirshman, S.P.

1992-01-01

A comparison is made of results from the PIES code, which determines the equilibrium properties of three-dimensional toroidal configurations by direct integration along the magnetic field lines, with those from the VMEC code, which uses an energy minimization in a flux representation to determine the equilibrium configuration, for two devices: the ATF stellarator at Oak Ridge and the TJ-11 heliac which is being built in Madrid. The results obtained from the two codes are in good agreement, providing additional validation for the codes

Regulation of microtubule-based transport by MAP4

Science.gov (United States)

Semenova, Irina; Ikeda, Kazuho; Resaul, Karim; Kraikivski, Pavel; Aguiar, Mike; Gygi, Steven; Zaliapin, Ilya; Cowan, Ann; Rodionov, Vladimir

2014-01-01

Microtubule (MT)-based transport of organelles driven by the opposing MT motors kinesins and dynein is tightly regulated in cells, but the underlying molecular mechanisms remain largely unknown. Here we tested the regulation of MT transport by the ubiquitous protein MAP4 using Xenopus melanophores as an experimental system. In these cells, pigment granules (melanosomes) move along MTs to the cell center (aggregation) or to the periphery (dispersion) by means of cytoplasmic dynein and kinesin-2, respectively. We found that aggregation signals induced phosphorylation of threonine residues in the MT-binding domain of the Xenopus MAP4 (XMAP4), thus decreasing binding of this protein to MTs. Overexpression of XMAP4 inhibited pigment aggregation by shortening dynein-dependent MT runs of melanosomes, whereas removal of XMAP4 from MTs reduced the length of kinesin-2–dependent runs and suppressed pigment dispersion. We hypothesize that binding of XMAP4 to MTs negatively regulates dynein-dependent movement of melanosomes and positively regulates kinesin-2–based movement. Phosphorylation during pigment aggregation reduces binding of XMAP4 to MTs, thus increasing dynein-dependent and decreasing kinesin-2–dependent motility of melanosomes, which stimulates their accumulation in the cell center, whereas dephosphorylation of XMAP4 during dispersion has an opposite effect. PMID:25143402

Effects of irradiation on the production of factors regulating humoral hematopoiesis

International Nuclear Information System (INIS)

Seki, Masatoshi; Yoshida, Kazuko

1974-01-01

Changes in factors regulating humoral hematopoiesis after irradiation were studied by intraperitoneal insertion of cellulose acetate membrane (CA membrane). There is little possibility that regulation factors is produced by macrophage itself. The growth of the colony depends mainly on increase or decrease of regulation factors in the host. However, there is a possibility that the macrophage interferes the action of these regulation factors. From the fact that there is no action of EPO (erythropoiesis) in Sl/slsup(d) mice having abnormal function of microenvironment, it is suggested that the action of EPO is brought about through the function of the microenvironment. In the analysis of the colony formation by intraperitoneal insertion of CA membrane, it is considered that the erythroblastic colony can be formed by the macrophage through the action of EPO. In short, it is concluded that factors regulating humoral hematopoiesis increased in the body of the mouse which have been irradiated to the whole body, and the increase in these factors is not constant, but remarkably changes with time. (Namekawa, K.)

49 CFR 176.4 - Port security and safety regulations.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Port security and safety regulations. 176.4... SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS CARRIAGE BY VESSEL General § 176.4 Port security and safety regulations. (a) Each carrier, master, agent, and charterer of a...

The impact of peripheral serotonin on leptin-brain serotonin axis, bone metabolism and strength in growing rats with experimental chronic kidney disease.

Science.gov (United States)

Pawlak, Dariusz; Domaniewski, Tomasz; Znorko, Beata; Oksztulska-Kolanek, Ewa; Lipowicz, Paweł; Doroszko, Michał; Karbowska, Malgorzata; Pawlak, Krystyna

2017-12-01

Chronic kidney disease (CKD) results in decreased bone strength. Serotonin (5-HT) is one of the critical regulators of bone health, fulfilling distinct functions depending on its synthesis site: brain-derived serotonin (BDS) favors osteoblast proliferation, whereas gut-derived serotonin (GDS) inhibits it. We assessed the role of BDS and peripheral leptin in the regulation of bone metabolism and strength in young rats with 5/6 nephrectomy. BDS synthesis was accelerated during CKD progression. Decreased peripheral leptin in CKD rats was inversely related to BDS content in the hypothalamus, brainstem and frontal cortex. Serotonin in these brain regions affected bone strength and metabolism in the studied animals. The direct effect of circulating leptin on bone was not shown in uremia. At the molecular level, there was an inverse association between elevated GDS and the expression of cAMP responsive element-binding protein (Creb) gene in bone of CKD animals. In contrast, increased expression of activating transcription factor 4 (Atf4) was shown, which was associated with GDS-dependent transcription factor 1 (Foxo1), clock gene - Cry-1, cell cycle genes: c-Myc, cyclins, and osteoblast differentiation genes. These results identified a previously unknown molecular pathway, by which elevated GDS can shift in Foxo1 target genes from Creb to Atf4-dependent response, disrupting the leptin-BDS - dependent gene pathway in the bone of uremic rats. Thus, in the condition of CKD the effect of BDS and GDS on bone metabolism and strength can't be distinguished. Copyright © 2017 Elsevier Inc. All rights reserved.

Melanocortin-4 receptor activation stimulates hypothalamic brain-derived neurotrophic factor release to regulate food intake, body temperature and cardiovascular function.

Science.gov (United States)

Nicholson, J R; Peter, J-C; Lecourt, A-C; Barde, Y-A; Hofbauer, K G

2007-12-01

In the present study, we aimed to investigate the neuromodulatory role played by hypothalamic brain-derived neurotrophic factor (BDNF) in the regulation of acute cardiovascular and feeding responses to melanocortin-4 receptor (MC4R) activation. In vitro, a selective MC4R agonist, MK1, stimulated BDNF release from isolated rat hypothalami and this effect was blocked by preincubation with the MC3/4R antagonist SHU-9119. In vivo, peripheral administration of MK1 decreased food intake in rats and this effect was blocked by pretreatment with an anti-BDNF antibody administered into the third ventricle. When anorexia was induced with the cannabinoid-1 receptor (CB1R) antagonist AM251, the anti-BDNF antibody did not prevent the reduction in food intake. Peripheral administration of MK1 also increased mean arterial pressure, heart rate and body temperature. These effects were prevented by pretreatment with the anti-BDNF antibody whereas the intracerebroventricular administration of BDNF caused changes similar to those of MK1. These findings demonstrate for the first time that activation of MC4R leads to an acute release of BDNF in the hypothalamus. This release is a prerequisite for MC4R-induced effects on appetite, body temperature and cardiovascular function. By contrast, CB1R antagonist-mediated anorexia is independent of the MC4R/BDNF pathway. Overall, these results show that BDNF is an important downstream mediator of the MC4R pathway.

A nontranscriptional role for Oct4 in the regulation of mitotic entry

Science.gov (United States)

Zhao, Rui; Deibler, Richard W.; Lerou, Paul H.; Ballabeni, Andrea; Heffner, Garrett C.; Cahan, Patrick; Unternaehrer, Juli J.; Kirschner, Marc W.; Daley, George Q.

2014-01-01

Rapid progression through the cell cycle and a very short G1 phase are defining characteristics of embryonic stem cells. This distinct cell cycle is driven by a positive feedback loop involving Rb inactivation and reduced oscillations of cyclins and cyclin-dependent kinase (Cdk) activity. In this setting, we inquired how ES cells avoid the potentially deleterious consequences of premature mitotic entry. We found that the pluripotency transcription factor Oct4 (octamer-binding transcription factor 4) plays an unappreciated role in the ES cell cycle by forming a complex with cyclin–Cdk1 and inhibiting Cdk1 activation. Ectopic expression of Oct4 or a mutant lacking transcriptional activity recapitulated delayed mitotic entry in HeLa cells. Reduction of Oct4 levels in ES cells accelerated G2 progression, which led to increased chromosomal missegregation and apoptosis. Our data demonstrate an unexpected nontranscriptional function of Oct4 in the regulation of mitotic entry. PMID:25324523

Membrane-bound transcription factors: regulated release by RIP or RUP.

Science.gov (United States)

Hoppe, T; Rape, M; Jentsch, S

2001-06-01

Regulated nuclear transport of transcription factors from cytoplasmic pools is a major route by which eukaryotes control gene expression. Exquisite examples are transcription factors that are kept in a dormant state in the cytosol by membrane anchors; such proteins are released from membranes by proteolytic cleavage, which enables these transcription factors to enter the nucleus. Cleavage can be mediated either by regulated intramembrane proteolysis (RIP) catalysed by specific membrane-bound proteases or by regulated ubiquitin/proteasome-dependent processing (RUP). In both cases processing can be controlled by cues that originate at or in the vicinity of the membrane.

Adenovirus Protein E4-ORF1 Activation of PI3 Kinase Reveals Differential Regulation of Downstream Effector Pathways in Adipocytes.

Science.gov (United States)

Chaudhary, Natasha; Gonzalez, Eva; Chang, Sung-Hee; Geng, Fuqiang; Rafii, Shahin; Altorki, Nasser K; McGraw, Timothy E

2016-12-20

Insulin activation of phosphatidylinositol 3-kinase (PI3K) regulates metabolism, including the translocation of the Glut4 glucose transporter to the plasma membrane and inactivation of the FoxO1 transcription factor. Adenoviral protein E4-ORF1 stimulates cellular glucose metabolism by mimicking growth-factor activation of PI3K. We have used E4-ORF1 as a tool to dissect PI3K-mediated signaling in adipocytes. E4-ORF1 activation of PI3K in adipocytes recapitulates insulin regulation of FoxO1 but not regulation of Glut4. This uncoupling of PI3K effects occurs despite E4-ORF1 activating PI3K and downstream signaling to levels achieved by insulin. Although E4-ORF1 does not fully recapitulate insulin's effects on Glut4, it enhances insulin-stimulated insertion of Glut4-containing vesicles to the plasma membrane independent of Rab10, a key regulator of Glut4 trafficking. E4-ORF1 also stimulates plasma membrane translocation of ubiquitously expressed Glut1 glucose transporter, an effect that is likely essential for E4-ORF1 to promote an anabolic metabolism in a broad range of cell types. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Adenovirus Protein E4-ORF1 Activation of PI3 Kinase Reveals Differential Regulation of Downstream Effector Pathways in Adipocytes

Directory of Open Access Journals (Sweden)

Natasha Chaudhary

2016-12-01

Full Text Available Insulin activation of phosphatidylinositol 3-kinase (PI3K regulates metabolism, including the translocation of the Glut4 glucose transporter to the plasma membrane and inactivation of the FoxO1 transcription factor. Adenoviral protein E4-ORF1 stimulates cellular glucose metabolism by mimicking growth-factor activation of PI3K. We have used E4-ORF1 as a tool to dissect PI3K-mediated signaling in adipocytes. E4-ORF1 activation of PI3K in adipocytes recapitulates insulin regulation of FoxO1 but not regulation of Glut4. This uncoupling of PI3K effects occurs despite E4-ORF1 activating PI3K and downstream signaling to levels achieved by insulin. Although E4-ORF1 does not fully recapitulate insulin’s effects on Glut4, it enhances insulin-stimulated insertion of Glut4-containing vesicles to the plasma membrane independent of Rab10, a key regulator of Glut4 trafficking. E4-ORF1 also stimulates plasma membrane translocation of ubiquitously expressed Glut1 glucose transporter, an effect that is likely essential for E4-ORF1 to promote an anabolic metabolism in a broad range of cell types.

34 CFR 350.4 - What regulations apply?

Science.gov (United States)

2010-07-01

... (IRB) reviews research that purposefully requires inclusion of children with disabilities or... REHABILITATIVE SERVICES, DEPARTMENT OF EDUCATION DISABILITY AND REHABILITATION RESEARCH PROJECTS AND CENTERS PROGRAM General § 350.4 What regulations apply? The following regulations apply to the Disability and...

Viability of thin wall tube forming of ATF FeCrAl

Energy Technology Data Exchange (ETDEWEB)

Maloy, Stuart Andrew [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Aydogan, Eda [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Anderoglu, Osman [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lavender, Curt [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Yamamoto, Yukinori [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2016-09-16

Fabrication of thin walled tubing of FeCrAl alloys is critical to its success as a candidate enhanced accident-tolerant fuel cladding material. Alloys that are being investigated are Generation I and Generation II FeCrAl alloys produced at ORNL and an ODS FeCrAl alloy, MA-956 produced by Special Metals. Gen I and Gen II FeCrAl alloys were provided by ORNL and MA-956 was provided by LANL (initially produced by Special Metals). Three tube development efforts were undertaken. ORNL led the FeCrAl Gen I and Gen II alloy development and tube processing studies through drawing tubes at Rhenium Corporation. LANL received alloys from ORNL and led tube processing studies through drawing tubes at Century Tubing. PNNL led the development of tube processing studies on MA-956 through pilger processing working with Sandvik Corporation. A summary of the recent progress on tube development is provided in the following report and a separate ORNL report: ORNL/TM-2015/478, “Development and Quality Assessments of Commercial Heat Production of ATF FeCrAl Tubes”.

The E. coli Global Regulator DksA Reduces Transcription during T4 Infection

Directory of Open Access Journals (Sweden)

Jennifer Patterson-West

2018-06-01

Full Text Available Bacteriophage T4 relies on host RNA polymerase to transcribe three promoter classes: early (Pe, requires no viral factors, middle (Pm, requires early proteins MotA and AsiA, and late (Pl, requires middle proteins gp55, gp33, and gp45. Using primer extension, RNA-seq, RT-qPCR, single bursts, and a semi-automated method to document plaque size, we investigated how deletion of DksA or ppGpp, two E. coli global transcription regulators, affects T4 infection. Both ppGpp0 and ΔdksA increase T4 wild type (wt plaque size. However, ppGpp0 does not significantly alter burst size or latent period, and only modestly affects T4 transcript abundance, while ΔdksA increases burst size (2-fold without affecting latent period and increases the levels of several Pe transcripts at 5 min post-infection. In a T4motAam infection, ΔdksA increases plaque size and shortens latent period, and the levels of specific middle RNAs increase due to more transcription from Pe’s that extend into these middle genes. We conclude that DksA lowers T4 early gene expression. Consequently, ΔdksA results in a more productive wt infection and ameliorates the poor expression of middle genes in a T4motAam infection. As DksA does not inhibit Pe transcription in vitro, regulation may be indirect or perhaps requires additional factors.

7 CFR 944.503 - Table Grape Import Regulation 4.

Science.gov (United States)

2010-01-01

... 7 Agriculture 8 2010-01-01 2010-01-01 false Table Grape Import Regulation 4. 944.503 Section 944...; IMPORT REGULATIONS § 944.503 Table Grape Import Regulation 4. (a)(1) Pursuant to section 8e of the Act... Vinifera species table grapes, except Emperor, Calmeria, Almeria, and Ribier varieties, is prohibited...

Genes and Gene Networks Involved in Sodium Fluoride-Elicited Cell Death Accompanying Endoplasmic Reticulum Stress in Oral Epithelial Cells

Directory of Open Access Journals (Sweden)

Yoshiaki Tabuchi

2014-05-01

Full Text Available Here, to understand the molecular mechanisms underlying cell death induced by sodium fluoride (NaF, we analyzed gene expression patterns in rat oral epithelial ROE2 cells exposed to NaF using global-scale microarrays and bioinformatics tools. A relatively high concentration of NaF (2 mM induced cell death concomitant with decreases in mitochondrial membrane potential, chromatin condensation and caspase-3 activation. Using 980 probe sets, we identified 432 up-regulated and 548 down-regulated genes, that were differentially expressed by >2.5-fold in the cells treated with 2 mM of NaF and categorized them into 4 groups by K-means clustering. Ingenuity® pathway analysis revealed several gene networks from gene clusters. The gene networks Up-I and Up-II included many up-regulated genes that were mainly associated with the biological function of induction or prevention of cell death, respectively, such as Atf3, Ddit3 and Fos (for Up-I and Atf4 and Hspa5 (for Up-II. Interestingly, knockdown of Ddit3 and Hspa5 significantly increased and decreased the number of viable cells, respectively. Moreover, several endoplasmic reticulum (ER stress-related genes including, Ddit3, Atf4 and Hapa5, were observed in these gene networks. These findings will provide further insight into the molecular mechanisms of NaF-induced cell death accompanying ER stress in oral epithelial cells.

Upgrade of MHD data acquisition system from ISX-B [Impurity Study Experiment] to ATF [Advanced Toroidal Facility

International Nuclear Information System (INIS)

Bell, J.D.; Pare, V.L.

1987-01-01

The data acquisition system assembled to study magnetohydrodynamic (MHD) activity on the Impurity Study Experiment (ISX-B) tokamak at Oak Ridge National Laboratory (ORNL) is being revised for use on the Advanced Toroidal Facility (ATF). The new hardware and software architectures are based on ISX-B experience and will feature different modes of operation for storing various subsets of available data, a user interface that requires less routine activity than the earlier system, and continued support of calibration and testing measurement used on ISX-B. The new hardware organization and software components are described in detail. 2 refs., 5 figs., 1 tab

Fibroblast growth factor receptor 4 regulates tumor invasion by coupling fibroblast growth factor signaling to extracellular matrix degradation

DEFF Research Database (Denmark)

Sugiyama, Nami; Varjosalo, Markku; Meller, Pipsa

2010-01-01

/stroma border and tumor invasion front. The strongest overall coexpression was found in prostate carcinoma. Studies with cultured prostate carcinoma cell lines showed that the FGFR4-R388 variant, which has previously been associated with poor cancer prognosis, increased MT1-MMP-dependent collagen invasion......Aberrant expression and polymorphism of fibroblast growth factor receptor 4 (FGFR4) has been linked to tumor progression and anticancer drug resistance. We describe here a novel mechanism of tumor progression by matrix degradation involving epithelial-to-mesenchymal transition in response...... to membrane-type 1 matrix metalloproteinase (MT1-MMP, MMP-14) induction at the edge of tumors expressing the FGFR4-R388 risk variant. Both FGFR4 and MT1-MMP were upregulated in tissue biopsies from several human cancer types including breast adenocarcinomas, where they were partially coexpressed at the tumor...