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Wang H, Shi Y, Zhou X, Zhang L, Yang A, Zhou D, Ma T. HNRNPA2B1 stabilizes NFATC3 levels to potentiate its combined actions with FOSL1 to mediate vasculogenic mimicry in GBM cells. Cell Biol Toxicol 2024; 40:44. [PMID: 38862832 PMCID: PMC11166796 DOI: 10.1007/s10565-024-09890-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Accepted: 06/03/2024] [Indexed: 06/13/2024]
Abstract
BACKGROUND Vasculogenic mimicry (VM) is an enigmatic physiological feature that influences blood supply within glioblastoma (GBM) tumors for their sustained growth. Previous studies identify NFATC3, FOSL1 and HNRNPA2B1 as significant mediators of VEGFR2, a key player in vasculogenesis, and their molecular relationships may be crucial for VM in GBM. AIMS The aim of this study was to understand how NFATC3, FOSL1 and HNRNPA2B1 collectively influence VM in GBM. METHODS We have investigated the underlying gene regulatory mechanisms for VM in GBM cell lines U251 and U373 in vitro and in vivo. In vitro cell-based assays were performed to explore the role of NFATC3, FOSL1 and HNRNPA2B1 in GBM cell proliferation, VM and migration, in the context of RNA interference (RNAi)-mediated knockdown alongside corresponding controls. Western blotting and qRT-PCR assays were used to examine VEGFR2 expression levels. CO-IP was employed to detect protein-protein interactions, ChIP was used to detect DNA-protein complexes, and RIP was used to detect RNA-protein complexes. Histochemical staining was used to detect VM tube formation in vivo. RESULTS Focusing on NFATC3, FOSL1 and HNRNPA2B1, we found each was significantly upregulated in GBM and positively correlated with VM-like cellular behaviors in U251 and U373 cell lines. Knockdown of NFATC3, FOSL1 or HNRNPA2B1 each resulted in decreased levels of VEGFR2, a key growth factor gene that drives VM, as well as the inhibition of proliferation, cell migration and extracorporeal VM activity. Chromatin immunoprecipitation (ChIP) studies and luciferase reporter gene assays revealed that NFATC3 binds to the promoter region of VEGFR2 to enhance VEGFR2 gene expression. Notably, FOSL1 interacts with NFATC3 as a co-factor to potentiate the DNA-binding capacity of NFATC3, resulting in enhanced VM-like cellular behaviors. Also, level of NFATC3 protein in cells was enhanced through HNRNPA2B1 binding of NFATC3 mRNA. Furthermore, RNAi-mediated silencing of NFATC3, FOSL1 and HNRNPA2B1 in GBM cells reduced their capacity for tumor formation and VM-like behaviors in vivo. CONCLUSION Taken together, our findings identify NFATC3 as an important mediator of GBM tumor growth through its molecular and epistatic interactions with HNRNPA2B1 and FOSL1 to influence VEGFR2 expression and VM-like cellular behaviors.
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Affiliation(s)
- Hanting Wang
- Department of Neurobiology, School of Life Sciences, China Medical University, Shenyang, 110122, China
| | - Yiwen Shi
- Department of Neurobiology, School of Life Sciences, China Medical University, Shenyang, 110122, China
| | - Xinxin Zhou
- Liaoning University of Traditional Chinese Medicine, Shenyang, 110034, China
| | - Lu Zhang
- Department of Neurobiology, School of Life Sciences, China Medical University, Shenyang, 110122, China
| | - Aodan Yang
- The First Clinical College of China Medical University, Shenyang, 110002, China
| | - Dabo Zhou
- School and Hospital of Stomatology, China Medical University, Shenyang, 110002, China.
| | - Teng Ma
- Department of Neurobiology, School of Life Sciences, China Medical University, Shenyang, 110122, China.
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Nolze A, Matern S, Grossmann C. Calcineurin Is a Universal Regulator of Vessel Function-Focus on Vascular Smooth Muscle Cells. Cells 2023; 12:2269. [PMID: 37759492 PMCID: PMC10528183 DOI: 10.3390/cells12182269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 09/05/2023] [Accepted: 09/08/2023] [Indexed: 09/29/2023] Open
Abstract
Calcineurin, a serine/threonine phosphatase regulating transcription factors like NFaT and CREB, is well known for its immune modulatory effects and role in cardiac hypertrophy. Results from experiments with calcineurin knockout animals and calcineurin inhibitors indicate that calcineurin also plays a crucial role in vascular function, especially in vascular smooth muscle cells (VSMCs). In the aorta, calcineurin stimulates the proliferation and migration of VSMCs in response to vascular injury or angiotensin II administration, leading to pathological vessel wall thickening. In the heart, calcineurin mediates coronary artery formation and VSMC differentiation, which are crucial for proper heart development. In pulmonary VSMCs, calcineurin/NFaT signaling regulates the release of Ca2+, resulting in increased vascular tone followed by pulmonary arterial hypertension. In renal VSMCs, calcineurin regulates extracellular matrix secretion promoting fibrosis development. In the mesenteric and cerebral arteries, calcineurin mediates a phenotypic switch of VSMCs leading to altered cell function. Gaining deeper insights into the underlying mechanisms of calcineurin signaling will help researchers to understand developmental and pathogenetical aspects of the vasculature. In this review, we provide an overview of the physiological function and pathophysiology of calcineurin in the vascular system with a focus on vascular smooth muscle cells in different organs. Overall, there are indications that under certain pathological settings reduced calcineurin activity seems to be beneficial for cardiovascular health.
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Affiliation(s)
| | | | - Claudia Grossmann
- Julius Bernstein Institute of Physiology, Martin Luther University Halle-Wittenberg, 06112 Halle (Saale), Germany
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Lin Y, Song Y, Zhang Y, Shi M, Hou A, Han S. NFAT signaling dysregulation in cancer: Emerging roles in cancer stem cells. Biomed Pharmacother 2023; 165:115167. [PMID: 37454598 DOI: 10.1016/j.biopha.2023.115167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 07/08/2023] [Accepted: 07/11/2023] [Indexed: 07/18/2023] Open
Abstract
The nuclear factor of activated T cells (NFAT) was first identified as a transcriptional regulator of activated T cells. The NFAT family is involved in the development of tumors. Furthermore, recent evidence reveals that NFAT proteins regulate the development of inflammatory and immune responses. New discoveries have also been made about the mechanisms by which NFAT regulates cancer progression through cancer stem cells (CSC). Here, we discuss the role of the NFAT family in the immune system and various cancer types.
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Affiliation(s)
- Yibin Lin
- Department of Neurosurgery, The First Hospital of China Medical University, Shenyang 110001, China
| | - Yifu Song
- Department of Neurosurgery, The First Hospital of China Medical University, Shenyang 110001, China
| | - Yaochuan Zhang
- Department of Neurosurgery, The First Hospital of China Medical University, Shenyang 110001, China
| | - Mengwu Shi
- Department of Neurosurgery, The First Hospital of China Medical University, Shenyang 110001, China
| | - Ana Hou
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang 110001, China.
| | - Sheng Han
- Department of Neurosurgery, The First Hospital of China Medical University, Shenyang 110001, China.
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Huang H, Dong J, Jiang J, Yang F, Zheng Y, Wang S, Wang N, Ma J, Hou M, Ding Y, Meng L, Zhuo W, Yang D, Qian W, Chen Q, You G, Qian G, Gu L, Lv H. The role of FOXO4/NFAT2 signaling pathway in dysfunction of human coronary endothelial cells and inflammatory infiltration of vasculitis in Kawasaki disease. Front Immunol 2023; 13:1090056. [PMID: 36700213 PMCID: PMC9869249 DOI: 10.3389/fimmu.2022.1090056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 12/19/2022] [Indexed: 01/12/2023] Open
Abstract
Aims The Ca+/NFAT (Nuclear factor of activated T cells) signaling pathway activation is implicated in the pathogenesis of Kawasaki disease (KD); however, we lack detailed information regarding the regulatory network involved in the human coronary endothelial cell dysfunction and cardiovascular lesion development. Herein, we aimed to use mouse and endothelial cell models of KD vasculitis in vivo and in vitro to characterize the regulatory network of NFAT pathway in KD. Methods and Results Among the NFAT gene family, NFAT2 showed the strongest transcriptional activity in peripheral blood mononuclear cells (PBMCs) from patients with KD. Then, NFAT2 overexpression and knockdown experiments in Human coronary artery endothelial cells (HCAECs) indicated that NFAT2 overexpression disrupted endothelial cell homeostasis by regulation of adherens junctions, whereas its knockdown protected HCAECs from such dysfunction. Combined analysis using RNA-sequencing and transcription factor (TF) binding site analysis in the NFAT2 promoter region predicted regulation by Forkhead box O4 (FOXO4). Western blotting, chromatin immunoprecipitation, and luciferase assays validated that FOXO4 binds to the promoter and transcriptionally represses NFAT2. Moreover, Foxo4 knockout increased the extent of inflamed vascular tissues in a mouse model of KD vasculitis. Functional experiments showed that inhibition NFAT2 relieved Foxo4 knockout exaggerated vasculitis in vivo. Conclusions Our findings revealed the FOXO4/NFAT2 axis as a vital pathway in the progression of KD that is associated with endothelial cell homeostasis and cardiovascular inflammation development.
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Affiliation(s)
- Hongbiao Huang
- Department of Pediatrics, Institute of Pediatric Research, Children’s Hospital of Soochow University, Suzhou, Jiangsu, China,Department of Pediatrics, Fujian Provincial Hospital, Fujian Provincial Clinical College of Fujian Medical University, Fuzhou, Fujian, China,Epigenetics Laboratory, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Jinfeng Dong
- Department of Hematology, the First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, China
| | - Jiaqi Jiang
- Department of Pediatrics, Institute of Pediatric Research, Children’s Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Fang Yang
- Department of Pediatrics, Fujian Provincial Hospital, Fujian Provincial Clinical College of Fujian Medical University, Fuzhou, Fujian, China
| | - Yiming Zheng
- Department of Pediatrics, Institute of Pediatric Research, Children’s Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Shuhui Wang
- Department of Pediatrics, Institute of Pediatric Research, Children’s Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Nana Wang
- Department of Pediatrics, Institute of Pediatric Research, Children’s Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Jin Ma
- Department of Pediatrics, Institute of Pediatric Research, Children’s Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Miao Hou
- Department of Pediatrics, Institute of Pediatric Research, Children’s Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Yueyue Ding
- Department of Pediatrics, Institute of Pediatric Research, Children’s Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Lijun Meng
- Department of Hematology, Children’s Hospital of Soochow University, Suzhou, China
| | - Wenyu Zhuo
- Department of Pediatrics, Institute of Pediatric Research, Children’s Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Daoping Yang
- Department of Pediatrics, Institute of Pediatric Research, Children’s Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Weiguo Qian
- Department of Pediatrics, Institute of Pediatric Research, Children’s Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Qiaobin Chen
- Department of Pediatrics, Fujian Provincial Hospital, Fujian Provincial Clinical College of Fujian Medical University, Fuzhou, Fujian, China
| | - Guoping You
- Department of Emergency, Fujian Provincial Hospital, Fujian Provincial Clinical College of Fujian Medical University, Fuzhou, Fujian, China
| | - Guanghui Qian
- Department of Pediatrics, Institute of Pediatric Research, Children’s Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Lei Gu
- Epigenetics Laboratory, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany,Cardiopulmonary Institute (CPI), Bad Nauheim, Germany,*Correspondence: Haitao Lv, ; Lei Gu,
| | - Haitao Lv
- Department of Pediatrics, Institute of Pediatric Research, Children’s Hospital of Soochow University, Suzhou, Jiangsu, China,*Correspondence: Haitao Lv, ; Lei Gu,
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Jin YH, Kim DE, Jang MS, Min JS, Kwon S. Bavachin produces immunoadjuvant activity by targeting the NFAT signaling pathway. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2021; 93:153796. [PMID: 34689117 DOI: 10.1016/j.phymed.2021.153796] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 07/19/2021] [Accepted: 10/07/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Bavachin, a flavonoid compound isolated from the seeds and fruits of Psoralea corylifolia l. (family Fabaceae), is used as a traditional medicine in Asia. Indeed, it is reported to have various medicinal functions such as estrogenic and antiinflammatory activities among others. However, to date, the effects of bavachin on T cell activation have yet to be reported. PURPOSE AND STUDY DESIGN We aimed to determine the effects of bavachin on the activation of a human T cell line in vitro and on antigen-specific immune responses in mice in vivo. METHODS In a nuclear factor of activated T cells (NFAT) activity assay, the Jurkat T cell line expressing a luciferase reporter driven by an NFAT-response element was stimulated with antihuman CD3/CD28 antibody and bavachin. Furthermore, the level of cytokine production was measured in the Jurkat T cell line stimulated with phorbol 12-myristate 13-acetate/ionomycin and bavachin using an IL-2 ELISA and a cytometric bead array assay. For in vivo analyses, mice were subcutaneously immunized with an antigen (ovalbumin protein) and bavachin, and the immune responses of mice were analyzed by FACS analysis, a T cell proliferation assay, a cytokine ELISA, and an antiovalbumin-specific antibody ELISA. RESULTS We found that bavachin activated NFAT-mediated transcription in the human T cell line in vitro. In mice, when bavachin was administered with the antigen, an increase in T cell responses and antibody production specific to the antigen was observed. CONCLUSION Our results suggest that bavachin has immunoadjuvant and immunomodulation effects, which arise through activation of the NFAT signaling pathway.
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Affiliation(s)
- Young-Hee Jin
- KM Application Center, Korea Institute of Oriental Medicine, Daegu 41062, Korea; Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea.
| | - Dong Eon Kim
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea; KM Convergence Research Division, Korea Institute of Oriental Medicine, Daejeon 34054, Korea
| | - Min Seong Jang
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea; Department of Non-Clinical Studies, Korea Institute of Toxicology, Daejeon 34114, Korea
| | - Jung Sun Min
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea; KM Convergence Research Division, Korea Institute of Oriental Medicine, Daejeon 34054, Korea
| | - Sunoh Kwon
- Center for Convergent Research of Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon 34114, Korea; KM Convergence Research Division, Korea Institute of Oriental Medicine, Daejeon 34054, Korea.
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6
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Reinke S, Linge M, Diebner HH, Luksch H, Glage S, Gocht A, Robertson AAB, Cooper MA, Hofmann SR, Naumann R, Sarov M, Behrendt R, Roers A, Pessler F, Roesler J, Rösen-Wolff A, Winkler S. Non-canonical Caspase-1 Signaling Drives RIP2-Dependent and TNF-α-Mediated Inflammation In Vivo. Cell Rep 2021; 30:2501-2511.e5. [PMID: 32101731 DOI: 10.1016/j.celrep.2020.01.090] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 12/10/2019] [Accepted: 01/24/2020] [Indexed: 12/26/2022] Open
Abstract
Pro-inflammatory caspase-1 is a key player in innate immunity. Caspase-1 processes interleukin (IL)-1β and IL-18 to their mature forms and triggers pyroptosis. These caspase-1 functions are linked to its enzymatic activity. However, loss-of-function missense mutations in CASP1 do not prevent autoinflammation in patients, despite decreased IL-1β production. In vitro data suggest that enzymatically inactive caspase-1 drives inflammation via enhanced nuclear factor κB (NF-κB) activation, independent of IL-1β processing. Here, we report two mouse models of enzymatically inactive caspase-1-C284A, demonstrating the relevance of this pathway in vivo. In contrast to Casp1-/- mice, caspase-1-C284A mice show pronounced hypothermia and increased levels of the pro-inflammatory cytokines tumor necrosis factor alpha (TNF-α) and IL-6 when challenged with lipopolysaccharide (LPS). Caspase-1-C284A signaling is RIP2 dependent and mediated by TNF-α but independent of the NLRP3 inflammasome. LPS-stimulated whole blood from patients carrying loss-of-function missense mutations in CASP1 secretes higher amounts of TNF-α. Taken together, these results reveal non-canonical caspase-1 signaling in vivo.
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Affiliation(s)
- Sören Reinke
- Department of Pediatrics, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Mary Linge
- Department of Pediatrics, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Hans H Diebner
- Institute for Medical Informatics and Biometry, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Hella Luksch
- Department of Pediatrics, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Silke Glage
- Institute for Laboratory Animal Science, Hannover Medical School, Hannover, Germany
| | - Anne Gocht
- Department of Pediatrics, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Avril A B Robertson
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Australia; Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia
| | - Matthew A Cooper
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia
| | - Sigrun R Hofmann
- Department of Pediatrics, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Ronald Naumann
- Transgenic Core Facility, Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Mihail Sarov
- Genome Engineering Facility, Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Rayk Behrendt
- Institute for Immunology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Axel Roers
- Institute for Immunology, Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Frank Pessler
- Twincore, Centre for Experimental and Clinical Infection Research, Hannover, Germany; Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Joachim Roesler
- Department of Pediatrics, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Angela Rösen-Wolff
- Department of Pediatrics, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Stefan Winkler
- Department of Pediatrics, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.
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Kang T, Ge M, Wang R, Tan Z, Zhang X, Zhu C, Liu H, Chen S. Arsenic sulfide induces RAG1-dependent DNA damage for cell killing by inhibiting NFATc3 in gastric cancer cells. J Exp Clin Cancer Res 2019; 38:487. [PMID: 31822296 PMCID: PMC6902349 DOI: 10.1186/s13046-019-1471-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 11/04/2019] [Indexed: 12/26/2022] Open
Abstract
Background Arsenic sulfide was found to have potential anti-cancer activities, especially in gastric cancer. However, the underlying mechanism need to be further explored. This study was aimed to investigate the mechanism of arsenic compounds on gastric cancer. Methods Gastric cancer cell lines were infected with lentiviral vector carrying shNFATc3 and/or treated with arsenic sulfide. MTT assay were performed to assess cell growth. Flow cytometer assays were used to detect cell cycle and reactive oxygen species (ROS) level of gastric cancer cells. Western blot was carried out to detect nuclear factor of activated T-cells, cytoplasmic 3 (NFATc3), cell cycle markers, DNA damage pathway protein expression as well as other protein expression in gastric cancer cell lines. The expression of recombination activating gene 1 (RAG1) in gastric cancer cell lines was determined by RNA-sequencing analyses and Real-Time qPCR. The effect of NFATc3 on RAG1 were determined by CHIP-qPCR assay. The effect of arsenic sulfide on AGS cells was evaluated in vivo. Results We show that arsenic sulfide as well as knockdown of NFATc3 resulted in increased double-strand DNA damage in gastric cancer cells by increasing the expression of RAG1, an endonuclease essential for immunoglobulin V(D) J recombination. Overexpression of NFATc3 blocked the expression of RAG1 expression and DNA damage induced by arsenic sulfide. Arsenic sulfide induced cellular oxidative stress to redistribute NFATc3, thereby inhibiting its transcriptional function, which can be reversed by N-acetyl-L-cysteine (NAC). We show that NFATc3 targets the promoter of RAG1 for transcriptional inhibition. We further showed that NFATc3 upregulation and RAG1 downregulation significantly associated with poor prognosis in patients with gastric cancer. Our in vivo experiments further confirmed that arsenic sulfide exerted cytotoxic activity against gastric cancer cells through inhibiting NFATc3 to activate RAG1 pathway. Conclusion These results demonstrate that arsenic sulfide targets NFATc3 to induce double strand DNA break (DSB) for cell killing through activating RAG1 expression. Our results link arsenic compound to the regulation of DNA damage control and RAG1 expression as a mechanism for its cytotoxic effect.
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Protein Phosphatase 1α and Cofilin Regulate Nuclear Translocation of NF-κB and Promote Expression of the Anti-Inflammatory Cytokine Interleukin-10 by T Cells. Mol Cell Biol 2018; 38:MCB.00041-18. [PMID: 30181394 DOI: 10.1128/mcb.00041-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 08/23/2018] [Indexed: 02/07/2023] Open
Abstract
While several protein serine/threonine kinases control cytokine production by T cells, the roles of serine/threonine phosphatases are largely unexplored. Here, we analyzed the involvement of protein phosphatase 1α (PP1α) in cytokine synthesis following costimulation of primary human T cells. Small interfering RNA (siRNA)-mediated knockdown of PP1α (PP1KD) or expression of a dominant negative PP1α (D95N-PP1) drastically diminished interleukin-10 (IL-10) production. Focusing on a key transcriptional activator of human IL-10, we demonstrate that nuclear translocation of NF-κB was significantly inhibited in PP1KD or D95N-PP1 cells. Interestingly, knockdown of cofilin, a known substrate of PP1 containing a nuclear localization signal, also prevented nuclear accumulation of NF-κB. Expression of a constitutively active nonphosphorylatable S3A-cofilin in D95N-PP1 cells restored nuclear translocation of NF-κB and IL-10 expression. Subpopulation analysis revealed that defective nuclear translocation of NF-κB was most prominent in CD4+ CD45RA- CXCR3- T cells that included IL-10-producing TH2 cells. Together these findings reveal novel functions for PP1α and its substrate cofilin in T cells namely the regulation of the nuclear translocation of NF-κB and promotion of IL-10 production. These data suggest that stimulation of PP1α could limit the overwhelming immune responses seen in chronic inflammatory diseases.
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9
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Kaltschmidt B, Greiner JFW, Kadhim HM, Kaltschmidt C. Subunit-Specific Role of NF-κB in Cancer. Biomedicines 2018; 6:E44. [PMID: 29673141 PMCID: PMC6027219 DOI: 10.3390/biomedicines6020044] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 04/11/2018] [Accepted: 04/12/2018] [Indexed: 02/07/2023] Open
Abstract
The transcription factor NF-κB is a key player in inflammation, cancer development, and progression. NF-κB stimulates cell proliferation, prevents apoptosis, and could promote tumor angiogenesis as well as metastasis. Extending the commonly accepted role of NF-κB in cancer formation and progression, different NF-κB subunits have been shown to be active and of particular importance in distinct types of cancer. Here, we summarize overexpression data of the NF-κB subunits RELA, RELB, and c-REL (referring to the v-REL, which is the oncogene of Reticuloendotheliosis virus strain T) as well as of their upstream kinase inhibitor, namely inhibitor of κB kinases (IKK), in different human cancers, assessed by database mining. These data argue against a universal mechanism of cancer-mediated activation of NF-κB, and suggest a much more elaborated mode of NF-κB regulation, indicating a tumor type-specific upregulation of the NF-κB subunits. We further discuss recent findings showing the diverse roles of NF-κB signaling in cancer development and metastasis in a subunit-specific manner, emphasizing their specific transcriptional activity and the role of autoregulation. While non-canonical NF-κB RELB signaling is described to be mostly present in hematological cancers, solid cancers reveal constitutive canonical NF-κB RELA or c-REL activity. Providing a linkage to cancer therapy, we discuss the recently described pivotal role of NF-κB c-REL in regulating cancer-targeting immune responses. In addition, current strategies and ongoing clinical trials are summarized, which utilize genome editing or drugs to inhibit the NF-κB subunits for cancer treatment.
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Affiliation(s)
- Barbara Kaltschmidt
- AG Molecular Neurobiology, University of Bielefeld, 33615 Bielefeld, Germany.
| | | | - Hussamadin M Kadhim
- Department of Cell Biology, University of Bielefeld, 33615 Bielefeld, Germany.
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Abstract
Nuclear factor of activated T cells (NFAT) was first described almost three decades ago as a Ca
2+/calcineurin-regulated transcription factor in T cells. Since then, a large body of research uncovered the regulation and physiological function of different NFAT homologues in the immune system and many other tissues. In this review, we will discuss novel roles of NFAT in T cells, focusing mainly on its function in humoral immune responses, immunological tolerance, and the regulation of immune metabolism.
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Affiliation(s)
- Martin Vaeth
- Department of Pathology, New York University School of Medicine, New York, NY, 10016, USA
| | - Stefan Feske
- Department of Pathology, New York University School of Medicine, New York, NY, 10016, USA
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Interplay between Inflammation and Stemness in Cancer Cells: The Role of Toll-Like Receptor Signaling. J Immunol Res 2016; 2016:4368101. [PMID: 28116318 PMCID: PMC5223024 DOI: 10.1155/2016/4368101] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Revised: 11/22/2016] [Accepted: 12/05/2016] [Indexed: 02/08/2023] Open
Abstract
Cancer stem cells (CSCs) are a small population of cancer cells that exhibit stemness. These cells contribute to cancer metastasis, treatment resistance, and relapse following therapy; therefore, they may cause malignancy and reduce the success of cancer treatment. Nuclear factor kappa B- (NF-κB-) mediated inflammatory responses increase stemness in cancer cells, and CSCs constitutively exhibit higher NF-κB activation, which in turn increases their stemness. These opposite effects form a positive feedback loop that further amplifies inflammation and stemness in cancer cells, thereby expanding CSC populations in the tumor. Toll-like receptors (TLRs) activate NF-κB-mediated inflammatory responses when stimulated by carcinogenic microbes and endogenous molecules released from cells killed during cancer treatment. NF-κB activation by extrinsic TLR ligands increases stemness in cancer cells. Moreover, it was recently shown that increased NF-κB activity and inflammatory responses in CSCs may be caused by altered TLR signaling during the enrichment of stemness in cancer cells. Thus, the activation of TLR signaling by extrinsic and intrinsic factors drives a positive interplay between inflammation and stemness in cancer cells.
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Kato-Kogoe N, Ohyama H, Okano S, Yamanegi K, Yamada N, Hata M, Nishiura H, Abiko Y, Terada N, Nakasho K. Functional analysis of differences in transcriptional activity conferred by genetic variants in the 5' flanking region of the IL12RB2 gene. Immunogenetics 2015; 68:55-65. [PMID: 26552659 DOI: 10.1007/s00251-015-0882-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 11/01/2015] [Indexed: 10/24/2022]
Abstract
Interleukin 12 receptor β chain (IL12RB2) is a crucial regulatory factor involved in cell-mediated immune responses, and genetic variants of the gene encoding IL12RB2 are associated with susceptibility to various immune-related diseases. We previously demonstrated that haplotypes with single nucleotide polymorphisms (SNPs) in the 5' flanking region of IL12RB2, including -1035A>G (rs3762315) and -1023A>G (rs3762316), affect the expression of IL12RB2, thereby altering susceptibility to leprosy and periodontal diseases. In the present study, we identified transcription factors associated with the haplotype-specific transcriptional activity of IL12RB2 in T cells and NK cells. The -1023G polymorphism was found to create a consensus binding site for the transcription factor activating protein (AP)-1, and enzyme-linked immunosorbent assay (ELISA)-based binding assays showed that these SNPs enhanced AP-1 binding to this region. In reporter assays, suppression of JunB expression using siRNA eliminated differences in the -1035G/-1023G and -1035A/-1023A regions containing IL12RB2 promoter activity in Jurkat T cells and NK3.3 cells. These results suggested that the -1035/-1023 polymorphisms created differential binding affinities for JunB that could lead to differential IL12RB2 expression. Moreover, the -1035G and -1035A alleles formed binding sites for GATA-3 and myocyte enhancer factor-2 (MEF-2), respectively. Our data indicated that in addition to JunB, the SNP at -1035/-1023 influenced GATA-3 and MEF-2 binding affinity, potentially altering IL12RB2 transcriptional activity. These findings confirm the effects of rs3762315 and rs3762316 on IL12RB2 transcription. These genetic variants may alter cellular activation of T cells and NK cells and modify cell-mediated immune responses.
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Affiliation(s)
- Nahoko Kato-Kogoe
- Department of Pathology, Hyogo College of Medicine, Nishinomiya, Japan.
| | - Hideki Ohyama
- Department of Pathology, Hyogo College of Medicine, Nishinomiya, Japan
| | - Soichiro Okano
- Department of Biochemistry and Molecular Biology, Nihon University School of Dentistry at Matsudo, Matsudo, Japan
| | - Koji Yamanegi
- Department of Pathology, Hyogo College of Medicine, Nishinomiya, Japan
| | - Naoko Yamada
- Department of Pathology, Hyogo College of Medicine, Nishinomiya, Japan
| | - Masaki Hata
- Department of Pathology, Hyogo College of Medicine, Nishinomiya, Japan
| | - Hiroshi Nishiura
- Department of Pathology, Hyogo College of Medicine, Nishinomiya, Japan
| | - Yoshimitsu Abiko
- Department of Biochemistry and Molecular Biology, Nihon University School of Dentistry at Matsudo, Matsudo, Japan
| | - Nobuyuki Terada
- Department of Pathology, Hyogo College of Medicine, Nishinomiya, Japan
| | - Keiji Nakasho
- Department of Pathology, Hyogo College of Medicine, Nishinomiya, Japan
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Muhammad K, Alrefai H, Marienfeld R, Pham DAT, Murti K, Patra AK, Avots A, Bukur V, Sahin U, Kondo E, Klein-Hessling S, Serfling E. NF-κB factors control the induction of NFATc1 in B lymphocytes. Eur J Immunol 2014; 44:3392-402. [PMID: 25179582 DOI: 10.1002/eji.201444756] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 07/16/2014] [Accepted: 08/29/2014] [Indexed: 01/06/2023]
Abstract
In peripheral lymphocytes, the transcription factors (TFs) NF-κB, NFAT, and AP-1 are the prime targets of signals that emerge from immune receptors. Upon activation, these TFs induce gene networks that orchestrate the growth, expansion, and effector function of peripheral lymphocytes. NFAT and NF-κB factors share several properties, such as a similar mode of induction and architecture in their DNA-binding domain, and there is a subgroup of κB-like DNA promoter motifs that are bound by both types of TFs. However, unlike NFAT and AP-1 factors that interact and collaborate in binding to DNA, NFAT, and NF-κB seem neither to interact nor to collaborate. We show here that NF-κB1/p50 and c-Rel, the most prominent NF-κB proteins in BCR-induced splenic B cells, control the induction of NFATc1/αA, a prominent short NFATc1 isoform. In part, this is mediated through two composite κB/NFAT-binding sites in the inducible Nfatc1 P1 promoter that directs the induction of NFATc1/αA by BCR signals. In concert with coreceptor signals that induce NF-κB factors, BCR signaling induces a persistent generation of NFATc1/αA. These data suggest a tight connection between NFATc1 and NF-κB induction in B lymphocytes contributing to the effector function of peripheral B cells.
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Affiliation(s)
- Khalid Muhammad
- Department of Molecular Pathology, Institute of Pathology and Comprehensive Cancer Center Mainfranken, University of Würzburg, Würzburg, Germany
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14
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Chi H, Xiao ZZ, Sun L. Nuclear factor 45 of half smooth tongue sole Cynoglossus semilaevis: gene structure, expression profile, and immunoregulatory property. FISH & SHELLFISH IMMUNOLOGY 2013; 35:972-978. [PMID: 23872474 DOI: 10.1016/j.fsi.2013.07.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2013] [Revised: 06/23/2013] [Accepted: 07/09/2013] [Indexed: 06/02/2023]
Abstract
Nuclear factor 45 (NF45) is a component of the protein complex called nuclear factor of activated T-cells (NFAT), which in mammals regulates interleukin (IL)-2 expression. To date very little is known about fish NF45. In this study, we identified a NF45 (named CsNF45) from half smooth tongue sole Cynoglossus semilaevis and examined its gene organization, expression profile, and regulatory function. We found that CsNF45 is composed of 387 residues and shares 90.3%-97.9% overall sequence identities with the NF45 of human and teleosts. Genetic analysis showed that the genomic sequence of the ORF region of CsNF45 consists of 14 exons and 13 introns. Constitutive expression of CsNF45 occurred in multiple tissues including gill, muscle, brain, heart, liver, head kidney, spleen, and gut. Experimental infection with viral and bacterial pathogens upregulated the expression of CsNF45 in head kidney and spleen in a time-dependent manner. Transient transfection analysis showed that CsNF45 was localized in the nucleus and able to stimulate the activity of mouse IL-2 promoter. These results indicate that CsNF45 possesses immunoregulatory property and is possibly involved in host immune defense against bacterial and viral infection.
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Affiliation(s)
- Heng Chi
- Institute of Oceanology, Chinese Academy of Sciences, 7 Nanhai Road, Qingdao 266071, China
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15
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Abstract
The nuclear factor-κB (NF-κB) transcription factor family has been considered the central mediator of the inflammatory process and a key participant in innate and adaptive immune responses. Coincident with the molecular cloning of NF-κB/RelA and identification of its kinship to the v-Rel oncogene, it was anticipated that NF-κB itself would be involved in cancer development. Oncogenic activating mutations in NF-κB genes are rare and have been identified only in some lymphoid malignancies, while most NF-κB activating mutations in lymphoid malignancies occur in upstream signaling components that feed into NF-κB. NF-κB activation is also prevalent in carcinomas, in which NF-κB activation is mainly driven by inflammatory cytokines within the tumor microenvironment. Importantly, however, in all malignancies, NF-κB acts in a cell type-specific manner: activating survival genes within cancer cells and inflammation-promoting genes in components of the tumor microenvironment. Yet, the complex biological functions of NF-κB have made its therapeutic targeting a challenge.
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Affiliation(s)
- Joseph A DiDonato
- Cleveland Clinic Foundation, Department of Cell Biology, Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine, USA
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16
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Zhang J, Lee SM, Shannon S, Gao B, Chen W, Chen A, Divekar R, McBurney MW, Braley-Mullen H, Zaghouani H, Fang D. The type III histone deacetylase Sirt1 is essential for maintenance of T cell tolerance in mice. J Clin Invest 2010; 119:3048-58. [PMID: 19729833 DOI: 10.1172/jci38902] [Citation(s) in RCA: 229] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2009] [Accepted: 06/24/2009] [Indexed: 12/19/2022] Open
Abstract
Although many self-reactive T cells are eliminated by negative selection in the thymus, some of these cells escape into the periphery, where they must be controlled by additional mechanisms. However, the molecular mechanisms underlying peripheral T cell tolerance and its maintenance remain largely undefined. In this study, we report that sirtuin 1 (Sirt1), a type III histone deacetylase, negatively regulates T cell activation and plays a major role in clonal T cell anergy in mice. In vivo, we found that loss of Sirt1 function resulted in abnormally increased T cell activation and a breakdown of CD4+ T cell tolerance. Conversely, upregulation of Sirt1 expression led to T cell anergy, in which the activity of the transcription factor AP-1 was substantially diminished.Furthermore, Sirt1 interacted with and deacetylated c-Jun, yielding an inactive AP-1 factor. In addition, Sirt1-deficient mice were unable to maintain T cell tolerance and developed severe experimental allergic encephalomyelitis as well as spontaneous autoimmunity. These findings provide insight into the molecular mechanisms of T cell activation and anergy, and we suggest that activators of Sirt1 may be useful as therapeutic agents for the treatment and/or prevention of autoimmune diseases.
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Affiliation(s)
- Jinping Zhang
- Department of Otolaryngology-Head and Neck Surgery,University of Missouri, Columbia, MO 65212, USA
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BCL11B enhances TCR/CD28-triggered NF-kappaB activation through up-regulation of Cot kinase gene expression in T-lymphocytes. Biochem J 2009; 417:457-66. [PMID: 18831712 DOI: 10.1042/bj20080925] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BCL11B is a transcriptional regulator with an important role in T-cell development and leukaemogenesis. We demonstrated recently that BCL11B controls expression from the IL (interleukin)-2 promoter through direct binding to the US1 (upstream site 1). In the present study, we provide evidence that BCL11B also participates in the activation of IL-2 gene expression by enhancing NF-kappaB (nuclear factor kappaB) activity in the context of TCR (T-cell receptor)/CD28-triggered T-cell activation. Enhanced NF-kappaB activation is not a consequence of BCL11B binding to the NF-kappaB response elements or association with the NF-kappaB-DNA complexes, but rather the result of higher translocation of NF-kappaB to the nucleus caused by enhanced degradation of IkappaB (inhibitor of NF-kappaB). The enhanced IkappaB degradation in cells with increased levels of BCL11B was specific for T-cells activated through the TCR, but not for cells activated through TNFalpha (tumour necrosis factor alpha) or UV light, and was caused by increased activity of IkappaB kinase, as indicated by its increase in phosphorylation. As BCL11B is a transcription factor, we investigated whether the expression of genes upstream of IkappaB kinase in the TCR/CD28 signalling pathway was affected by increased BCL11B expression, and found that Cot (cancer Osaka thyroid oncogene) kinase mRNA levels were elevated. Cot kinase is known to promote enhanced IkappaB kinase activity, which results in the phosphorylation and degradation of IkappaB and activation of NF-kappaB. The implied involvement of Cot kinase in BCL11B-mediated NF-kappaB activation in response to TCR activation is supported by the fact that a Cot kinase dominant-negative mutant or Cot kinase siRNA (small interfering RNA) knockdown blocked BCL11B-mediated NF-kappaB activation. In support of our observations, in the present study we report that BCL11B enhances the expression of several other NF-kappaB target genes, in addition to IL-2. In addition, we provide evidence that BCL11B associates with intron 2 of the Cot kinase gene to regulate its expression.
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Martins GA, Cimmino L, Liao J, Magnusdottir E, Calame K. Blimp-1 directly represses Il2 and the Il2 activator Fos, attenuating T cell proliferation and survival. ACTA ACUST UNITED AC 2008; 205:1959-65. [PMID: 18725523 PMCID: PMC2526191 DOI: 10.1084/jem.20080526] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Mice with a T cell–specific deletion of Prdm1, encoding Blimp-1, have aberrant T cell homeostasis and develop fatal colitis. In this study, we show that one critical activity of Blimp-1 in T cells is to repress IL-2, and that it does so by direct repression of Il2 transcription, and also by repression of Fos transcription. Using these mechanisms Blimp-1 participates in an autoregulatory loop by which IL-2 induces Prdm1 expression and thus represses its own expression after T cell activation, ensuring that the immune response is appropriately controlled. This activity of Blimp-1 is important for cytokine deprivation–induced T cell death and for attenuating T cell proliferation in antigen-specific responses both in vitro and in vivo.
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Affiliation(s)
- Gislâine A Martins
- Department of Microbiology, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.
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20
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Marusina AI, Burgess SJ, Pathmanathan I, Borrego F, Coligan JE. Regulation of human DAP10 gene expression in NK and T cells by Ap-1 transcription factors. THE JOURNAL OF IMMUNOLOGY 2008; 180:409-17. [PMID: 18097042 DOI: 10.4049/jimmunol.180.1.409] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Human NKG2D/DAP10 is an activation receptor expressed by NK and subsets of T cells, whose ligands include MHC class I chain-related (MIC) protein A and protein B and UL16-binding proteins that are often up-regulated by stress or pathological conditions. DAP10 is required for NKG2D/DAP10 cell surface expression and signaling capacity. Little is known about the mechanisms that regulate DAP10 gene expression. We describe the existence of multiple transcriptional start sites upstream of DAP10 exon 1 and identify the location of the basic promoter upstream of these starting sites. The promoter is active in NK and CD8+ T cells, but not in CD4+ T cells. We demonstrate TCR-mediated up-regulation of DAP10 transcription and found that a 40 bp region within the DAP10 promoter, containing an Ap-1 binding site, is largely responsible for this increased transcription. Using pull-down and chromatin immunoprecipitation assays, we show that the DAP10 promoter interacts with Ap-1 transcription factors in primary CD8+ T and NK cells in vitro and in vivo. Overexpression of c-Jun or c-Fos in NK and T cells led to enhanced DAP10 promoter activity and DAP10 protein expression. Taken together, our data indicate that Ap-1 is an important transcription factor for regulating DAP10 gene expression in human NK and T cells, and that Ap-1 plays a key role in the transactivation of DAP10 promoter following TCR stimulation.
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Affiliation(s)
- Alina I Marusina
- Receptor Cell Biology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852-1742, USA
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21
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Thomas RM, Chunder N, Chen C, Umetsu SE, Winandy S, Wells AD. Ikaros enforces the costimulatory requirement for IL2 gene expression and is required for anergy induction in CD4+ T lymphocytes. THE JOURNAL OF IMMUNOLOGY 2008; 179:7305-15. [PMID: 18025173 DOI: 10.4049/jimmunol.179.11.7305] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
T cell activation results in dynamic remodeling of the chromatin at the IL2 promoter and induction of IL2 gene transcription. These processes are each dependent upon CD28 costimulation, but the molecular basis for this requirement is not clear. The IL2 promoter contains consensus-binding elements for Ikaros, a lymphocyte-specific zinc-finger DNA-binding protein that can regulate gene expression by recruiting chromatin-remodeling complexes. We find that native Ikaros in CD4(+) T cells exhibits sequence-specific binding to these elements in vitro, and interacts with the endogenous IL2 promoter in vivo, in a manner dependent upon its DNA-binding domain. This binding has important consequences on the regulation of the IL2 gene, because CD4(+) T cells with reduced Ikaros DNA-binding activity no longer require signals from the TCR or CD28 for histone acetylation at the endogenous IL2 promoter, and no longer require CD28 costimulation for expression of the IL2 gene. Furthermore, CD4(+) T cells with reduced Ikaros activity are resistant to clonal anergy induced by TCR ligation in the absence of either CD28 or IL-2R signals. These results establish Ikaros as a transcriptional repressor of the IL2 gene that functions through modulation of chromatin structure and has an obligate role in the induction of anergy.
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Affiliation(s)
- Rajan M Thomas
- Joseph Stokes, Jr Research Institute, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
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22
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Wren JD, Wu Y, Guo SW. A system-wide analysis of differentially expressed genes in ectopic and eutopic endometrium. Hum Reprod 2007; 22:2093-102. [PMID: 17562676 DOI: 10.1093/humrep/dem129] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Decades of research suggest that endometriosis is a complex disorder, with varying severity, onset and progression. Many genes have been associated with endometriosis through a number of studies and now microarray analyses have added to the list of perturbed or differentially regulated genes. Thus, it is difficult to see 'the big picture' without first integrating these multiple, heterogeneous sources of high-quality information for analysis. METHODS The goal of this study was to infer correlative and/or causal trends by combining empirical microarray analysis with a historical knowledge base of genetic relationships in endometriosis via a program called IRIDESCENT. RESULTS Importantly, we found a number of genes, which may have a central role in endometriosis, despite the fact that few or no past studies have reported these associations. CONCLUSIONS Several genes listed as non-responders on the microarray were found to be regulated post-transcriptionally, illustrating the importance of integrating multiple data sources.
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Affiliation(s)
- Jonathan D Wren
- Arthritis and Immunology Research Program, Oklahoma Medical Research Foundation, 825 N.E. 13th Street, Oklahoma City, OK 73104-5005, USA.
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23
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Ghadiri A, Duhamel M, Fleischer A, Reimann A, Dessauge F, Rebollo A. Critical function of Ikaros in controlling Aiolos gene expression. FEBS Lett 2007; 581:1605-16. [PMID: 17383641 DOI: 10.1016/j.febslet.2007.03.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2006] [Revised: 03/04/2007] [Accepted: 03/06/2007] [Indexed: 10/23/2022]
Abstract
To characterize the regulation of lymphoid Aiolos transcription factor, we have cloned its promoter. Full promoter and nested deletions were expressed in lymphoid and non-lymphoid cell lines. The minimal promoter activity could be considered as a 172bp upstream from the ATG for Jurkat and HEK293 cells and as a 370bp fragment for U937 cells. Moreover, we have mapped the transcription initiation site. Retardation gels showed binding activity for Ikaros, NFkappaB and AP4 transcription factors and mutations in their binding sites abolish Aiolos promoter activity. Chromatin immunoprecipitation assay revealed that Ikaros, NFkappaB and AP4 are bound to Aiolos promoter. The important function of Ikaros and NFkappaB is underlined by their over expression, which results in the trans-activation of the promoter and drives Aiolos expression in cell lines and in freshly isolated B and T cells, while over expression of a dominant negative Ikaros isoform is able to block Aiolos expression.
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Affiliation(s)
- Ata Ghadiri
- Immunologie Cellulaire et Tissulaire, Hôpital Pitié-Salpêtrière, Bâtiment CERVI, U543 Inserm, 83, Bd de l'Hôpital, 75013 Paris, France
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24
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Abstract
Nickel is a widely distributed metal that is industrially applied in many forms. Accumulated epidemiological evidence confirms that exposures to nickel compounds are associated with increased nasal and lung cancer incidence, both in mostly occupational exposures. Although the molecular mechanisms by which nickel compounds cause cancer are still under intense investigation, the carcinogenic actions of nickel compounds are thought to involve oxidative stress, genomic DNA damage, epigenetic effects, and the regulation of gene expression by activation of certain transcription factors related to corresponding signal transduction pathways. The present review summarizes our current knowledge on the molecular mechanisms of nickel carcinogenesis, with special emphasis on the role of nickel induced reactive oxygen species (ROS) and signal transduction pathways.
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Affiliation(s)
- Haitian Lu
- Nelson Institute of Environmental Medicine, School of Medicine, New York University, Tuxedo, New York 10987, USA
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25
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Lu H, Li J, Zhang D, Stoner GD, Huang C. Molecular mechanisms involved in chemoprevention of black raspberry extracts: from transcription factors to their target genes. Nutr Cancer 2006; 54:69-78. [PMID: 16800774 DOI: 10.1207/s15327914nc5401_8] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Berries have attracted attention for their chemopreventive activities in last a few years. Dietary freeze-dried blackberries have been shown to reduce esophagus and colon cancer development induced by chemical carcinogen in rodents. To elucidate molecular mechanisms involved in chemoprevention by berry extracts, we employed mouse epidermal Cl 41 cell line, a well-characterized in vitro model in tumor promotion studies. Pretreatment of Cl 41 cells with methanol-extracted blackberry fraction RO-ME resulted in a dramatical inhibition of B(a)PDE-induced activation of AP-1 and NFkB, and expression of VEGF and COX-2. The inhibitory effects of RO-ME on B(a)PDE-induced activation of AP-1 and NFkappaB appear to be mediated via inhibition of MAPKs and IkappaBalpha phosphorylation, respectively. In view of the important roles of AP-1, NFkappaB, VEGF and COX-2 in tumor promotion/progression, and VEGF and COX-2 are target of AP-1 and NFkappaB, we anticipate that the ability of black raspberries to inhibit tumor development may be mediated by impairing signal transduction pathways leading to activation of AP-1 and NFkappaB, subsequently resulting in down-regulation of VEGF and COX-2 expression. The RO-ME fraction appears to be the major fraction responsible for the inhibitory activity of black raspberries.
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Affiliation(s)
- Haitian Lu
- Nelson Institute of Environmental Medicine, New York University School of Medicine, Tuxedo, NY 10987, USA
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26
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Jie KE, Verhaar MC, Cramer MJM, van der Putten K, Gaillard CAJM, Doevendans PA, Koomans HA, Joles JA, Braam B. Erythropoietin and the cardiorenal syndrome: cellular mechanisms on the cardiorenal connectors. Am J Physiol Renal Physiol 2006; 291:F932-44. [PMID: 16885153 DOI: 10.1152/ajprenal.00200.2006] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
We have recently proposed severe cardiorenal syndrome (SCRS), in which cardiac and renal failure mutually amplify progressive failure of both organs. This frequent pathophysiological condition has an extremely poor prognosis. Interactions between inflammation, the renin-angiotensin system, the balance between the nitric oxide and reactive oxygen species and the sympathetic nervous system form the cardiorenal connectors and are cornerstones in the pathophysiology of SCRS. An absolute deficit of erythropoietin (Epo) and decreased sensitivity to Epo in this syndrome both contribute to the development of anemia, which is more pronounced than renal anemia in the absence of heart failure. Besides expression on erythroid progenitor cells, Epo receptors are present in the heart, kidney, and vascular system, in which activation results in antiapoptosis, proliferation, and possibly antioxidation and anti-inflammation. Interestingly, Epo can improve cardiac and renal function. We have therefore reviewed the literature with respect to Epo and the cardiorenal connectors. Indeed, there are indications that Epo can diminish inflammation, reduce renin-angiotensin system activity, and shift the nitric oxide and reactive oxygen species balance toward nitric oxide. Information about Epo and the sympathetic nervous system is scarce. This analysis underscores the relevance of a further understanding of clinical and cellular mechanisms underlying protective effects of Epo, because this will support better treatment of SCRS.
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Affiliation(s)
- Kim E Jie
- Dept. of Nephrology and Hypertension, F03.223, Univ. Medical Ctr. Utrecht, Utrecht, The Netherlands
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27
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Lin HF, Shao JZ, Xiang LX, Wang HJ. Molecular cloning, characterization and expression analysis of grass carp (Ctenopharyngodon idellus) NF45 (ILF2) cDNA, a subunit of the nuclear factor of activated T-cells (NF-AT). FISH & SHELLFISH IMMUNOLOGY 2006; 21:385-92. [PMID: 16533607 DOI: 10.1016/j.fsi.2006.01.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2005] [Revised: 01/19/2006] [Accepted: 01/19/2006] [Indexed: 05/07/2023]
Abstract
NF45 (ILF2) and NF90 (ILF3) regulate the IL-2 gene transcription via interaction with the antigen receptor response element. Much work on NF45 has been done in human and mammals while little in fish. In the present study, we have cloned and characterized the full-length cDNA of NF45 in grass carp (Ctenopharyngodon idellus). The grass carp NF45 cDNA of 1563bp contains a short 5'UTR of 24bp, a 3'UTR of 375bp and an open reading frame of 1164bp coding for a protein of 387 aa with a predicted molecular mass of 42.8kDa. The encoded protein shares 86.3-96.7% identities to other homologues. RT-PCR was optimized to estimate the expression level of NF45 in grass carp. The results showed that NF45 is constitutively expressed in most selected tissues, including head kidney, spleen, heart, brain, liver, and gill, although low levels were observed in spleen, liver and gill. The ubiquitous expression of NF45 is consistent with a postulated role in gene regulation at the level of transcription. Stimulating the fish with PHA significantly up-regulated the expression of NF45 in most tissues examined, which potentially indicated that NF45 was involved in the immune responses triggered by PHA.
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Affiliation(s)
- Hui-Fang Lin
- College of Life Sciences, Zhejiang University, Hangzhou 310012, People's Republic of China
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Conde P, Acosta-Saavedra LC, Goytia-Acevedo RC, Calderon-Aranda ES. Sodium arsenite-induced inhibition of cell proliferation is related to inhibition of IL-2 mRNA expression in mouse activated T cells. Arch Toxicol 2006; 81:251-9. [PMID: 17009048 DOI: 10.1007/s00204-006-0152-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2006] [Accepted: 08/28/2006] [Indexed: 01/24/2023]
Abstract
A proposed mechanism for the As-induced inhibition of cell proliferation is the inhibition of IL-2 secretion. However, the effects of arsenite on IL-2 mRNA expression or on the ERK pathway in activated-T cells have not yet been described. We examined the effect of arsenite on IL-2 mRNA expression, cell activation and proliferation in PHA-stimulated murine lymphocytes. Arsenite (1 and 10 microM) decreased IL-2 mRNA expression, IL-2 secretion and cell proliferation. Arsenite (10 microM) strongly inhibited ERK-phosphorylation. However, the partial inhibition (50%) of IL-2 mRNA produced by 1 microM, consistent with the effects on IL-2 secretion and cell proliferation, could not be explained by the inhibition of ERK-phosphorylation, which was not affected at this concentration. The inhibition of IL-2 mRNA expression caused by 1 microM could be associated to effects on pathways located downstream or parallel to ERK. Arsenite also decreased early activation (surface CD69+ expression) in both CD4+ and CD8+, and decreased total CD8+ count without significantly affecting CD4+, supporting that the cellular immune response mediated by cytotoxic T cells is an arsenic target. Thus, our results suggest that arsenite decreases IL-2 mRNA levels and T-cell activation and proliferation. However, further studies on the effects of arsenite on IL-2 gene transcription and IL-2 mRNA stability are needed.
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Affiliation(s)
- Patricia Conde
- Sección Toxicología, Centro de Investigación y de Estudios Avanzados, CINVESTAV, P.O. Box 14-740, Mexico, D.F., 07360, Mexico
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Nandiwada SL, Li W, Zhang R, Mueller DL. p300/Cyclic AMP-responsive element binding-binding protein mediates transcriptional coactivation by the CD28 T cell costimulatory receptor. THE JOURNAL OF IMMUNOLOGY 2006; 177:401-13. [PMID: 16785536 DOI: 10.4049/jimmunol.177.1.401] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
During Ag stimulation of T cells, the recognition of B7 molecules by the CD28 costimulatory receptor increases the level of c-Fos, a component of the AP-1 transactivator known to bind the 5' Il2 gene enhancer. In this study, we show that the costimulation of Fos transcription by CD28 is associated with increased binding of p300/CREB-binding protein (CBP) molecules at the Fos promoter, and is blocked by an adenoviral E1A molecular antagonist of p300/CBP. Furthermore, transcriptional activation by a C-terminal domain of CBP is strengthened when CD28 molecules are actively signaling. This increased amount and activity of p300/CBP molecules at the Fos gene correlated with higher histone H4 acetylation and RNA polymerase II association with the promoter. These data suggest a global mechanism whereby CD28 signaling influences the rate and intensity of new gene expression during Ag recognition via direct control over the coactivator function of p300/CBP.
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Affiliation(s)
- Sarada L Nandiwada
- Rheumatic and Autoimmune Diseases Division, and Center for Immunology, University of Minnesota Medical School, 312 Church Street SE, Minneapolis, MN 55455, USA
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Li J, Lu H, Huang C. NFAT3 is Required for EGF-Induced COX-2 Transcription, but Neither iNOS Transcription Nor Cell Transformation in Cl 41 Cells. Mol Cell Biochem 2006; 289:73-82. [PMID: 16718377 DOI: 10.1007/s11010-006-9149-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2005] [Accepted: 02/03/2006] [Indexed: 10/24/2022]
Abstract
Epidermal growth factor (EGF) has been reported to act as a tumor promoter in several tissues, such as skin, in association with the induction of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). However, molecular mechanisms involved in these regulations are not well defined. This study addressed a potential role of nuclear factor of activated T cells 3 (NFAT3) in EGF-induced COX-2 and iNOS transcription and cell transformation in mouse epidermal Cl 41 cells. We found that EGF markedly induced anchorage-independent growth (cell transformation) of Cl 41 cells, as well as COX-2 (> 6-fold) and iNOS (> 5-fold) promoter-dependent transcription. The EGF-induced COX-2 transcription was blocked by knockdown of NFAT3 with NFAT3 siRNA, whereas the transcription of iNOS and cell transformation induced by EGF were not affected. Although our recent studies supported that NFAT3 plays an essential role in chemical carcinogen benzo[a]pyrene-7,8-diol-9,10-epoxide (B[a]PDE)-induced cell transformation, the data presented here demonstrated that NFAT3 is required for EGF-induced COX-2 transcription, but neither iNOS transcription nor cell transformation, indicating that the role of NFAT3 in regulating cell transformation is carcinogen-specific.
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Affiliation(s)
- Jingxia Li
- Nelson Institute of Environmental Medicine, New York University School of Medicine, 57 Old Forge Road, Tuxedo, NY 10987, USA
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31
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Mackenzie GG, Oteiza PI. Zinc and the cytoskeleton in the neuronal modulation of transcription factor NFAT. J Cell Physiol 2006; 210:246-56. [PMID: 17044076 DOI: 10.1002/jcp.20861] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Transcription factor NFAT is crucial in the development of the nervous system due to its role in neuronal plasticity and survival. In this study we characterized the role of zinc and the cytoskeleton in the modulation of NFAT in neuronal cells. The incubation of cells in zinc deficient media led to NFAT activation that was inhibited by the calcium chelator BAPTA and the antioxidants (+/-)-alpha-lipoic acid and N-acetyl cysteine, suggesting the involvement of calcium and oxidants in the initial steps of NFAT activation associated with zinc deficiency. At a second step of regulation, a decrease in cellular zinc led to an impaired transport of the active NFAT from the cytosol into the nucleus due to alterations in tubulin polymerization secondary to a decrease in neuronal zinc. Furthermore, disruption of the cytoskeleton structure by cold and chemical agents (colchicine (Col), vinblastine (VB), cytochalasin D (Cyt)) also inhibited NFAT transport into the nucleus. The altered nuclear transport caused a decrease in NFAT-dependent gene expression. This study demonstrates for the first time that zinc can modulate transcription factor NFAT in neuronal cells, and that microtubules are involved in NFAT nuclear translocation, crucial event in the regulation of NFAT transcriptional activity.
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Affiliation(s)
- Gerardo G Mackenzie
- Department of Nutrition, University of California, Davis, Davis California, USA
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32
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Waiczies S, Prozorovski T, Zipp F. Modulating T cell signaling cascades by HMG-CoA reductase inhibitors. ACTA ACUST UNITED AC 2005. [DOI: 10.1002/sita.200500058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Karin M, Gallagher E. From JNK to Pay Dirt: Jun Kinases, their Biochemistry, Physiology and Clinical Importance. IUBMB Life 2005; 57:283-95. [PMID: 16036612 DOI: 10.1080/15216540500097111] [Citation(s) in RCA: 317] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The c-Jun N-terminal kinases (JNKs) were originally identified by their ability to phosphorylate c-Jun in response to UV-irradiation, but now are recognized as critical regulators of various aspects of mammalian physiology, including: cell proliferation, cell survival, cell death, DNA repair and metabolism. JNK-mediated phosphorylation enhances the ability of c-Jun, a component of the AP-1 transcription factor, to activate transcription, in response to a plethora of extracellular stimuli. The JNK activation leads to induction of AP-1-dependent target genes involved in cell proliferation, cell death, inflammation, and DNA repair. The JNKs, which are encoded by three different Jnk loci, are now known to be regulated by many other stimuli, from pro-inflammatory cytokines to obesity, in addition to UV-irradiation. Targeted disruption of the Jnk loci in mice has proved to be a critical tool in better understanding their physiological functions. Such studies revealed that the JNKs play important roles in numerous cellular processes, including: programmed cell death, T cell differentiation, negative regulation of insulin signaling, control of fat deposition, and epithelial sheet migration. Importantly, the JNKs have become prime targets for drug development in several important clinical areas, including: inflammation, diabetes, and cancer.
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Affiliation(s)
- Michael Karin
- Department of Pharmacology, School of Medicine, University of California, San Diego, California 92093-0723, USA.
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34
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Gilbert KM, Whitlow AB, Pumford NR. Environmental contaminant and disinfection by-product trichloroacetaldehyde stimulates T cells in vitro. Int Immunopharmacol 2004; 4:25-36. [PMID: 14975357 DOI: 10.1016/j.intimp.2003.10.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2003] [Revised: 08/14/2003] [Accepted: 10/03/2003] [Indexed: 01/28/2023]
Abstract
It had been shown previously that MRL+/+ mice exposed to occupationally relevant doses of the environmental contaminant trichloroethylene in their drinking water developed lupus-like symptoms and autoimmune hepatitis in association with activation of Interferon-gamma (IFN-gamma)-producing CD4+ T cells. Since trichloroethylene must be metabolized in order to promote the T-cell activation associated with autoimmunity, the present study was initiated to determine whether the immunoregulatory effects of trichloroethylene could be mimicked by one of its major metabolites, trichloroacetaldehyde (TCAA). At concentrations ranging from 0.04 to 1 mM TCAA co-stimulated proliferation of murine T-helper type 1 (Th1) cells treated with anti-CD3 antibody or antigen in vitro. TCAA at similar concentrations also induced phenotypic alterations commensurate with activation (upregulation of CD28 and downregulation of CD62L) in both cloned memory Th1 cells, as well as naïve CD4+ T cells from MRL+/+ mice. TCAA-induced Th1 cell activation was accompanied by phoshorylation of activating transcription factor 2 (ATF-2) and c-Jun, two components of the activator protein-1 (AP-1) transcription factor. TCAA at higher concentrations was also shown to form a Schiff base on T cells, and inhibition of Schiff base formation suppressed the ability of TCAA to phosphorylate ATF-2. Taken together, these results suggest that TCAA promotes T-cell activation via stimulation of the mitogen-activated protein (MAP) kinase pathway in association with Schiff base formation on T-cell surface proteins. By demonstrating that TCAA can stimulate T-cell function directly, these results may explain how the environmental toxicant trichloroethylene promotes T-cell activation and related autoimmunity in vivo.
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Affiliation(s)
- Kathleen M Gilbert
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences/Arkansas Children's Hospital Research Institute, 1120 Marshall Street, Little Rock, AR 72205, USA.
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Abstract
Senescence is now established as a genetically controlled phenomenon that alters different cell functions, including proliferation, apoptosis, resistance to stress, and energetic metabolism. Underlying changes in gene expression are governed by some transcription factors, whose expression or activity must change with senescence as well. Transcription factors of the Rel/NF-kappa B family are good candidates to participate in the establishment of senescence. Arguments range from correlation between cell functions controlled by these factors and cell functions altered during senescence, to phenotypes resulting from in vitro manipulations of Rel/NF-kappa B activity.
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Affiliation(s)
- Karo Gosselin
- UMR 8117 CNRS-Institut Pasteur de Lille-Université Lille 1, Institut de Biologie de Lille, 1 rue Calmette, BP 447, 59021 Lille Cedex, France
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36
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Smith JL, Collins I, Chandramouli GVR, Butscher WG, Zaitseva E, Freebern WJ, Haggerty CM, Doseeva V, Gardner K. Targeting combinatorial transcriptional complex assembly at specific modules within the interleukin-2 promoter by the immunosuppressant SB203580. J Biol Chem 2003; 278:41034-46. [PMID: 12896977 DOI: 10.1074/jbc.m305615200] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The proximal promoter sequence of the interleukin-2 (IL-2) gene contains a series of composite sites or modules that controls much of its responsiveness to environmental stimuli. The integrated targeting of these modules is therefore a major mode of regulation. This report describes how multiple functional hierarchies, required for the recruitment of the p300 co-activator to the CD28RE/AP1 (TRE) module of the IL-2 promoter, are selectively disrupted in human T-cells by the immunosuppressive and anti-inflammatory actions of the p38 mitogen-activated protein kinase inhibitor (MAPK), SB203580. The molecular hierarchies targeted by SB203580 include the combinatorial interaction of NF-kappaB and CREB at the CD28RE/AP1 element coupled with the subsequent dynamic co-assembly and activation of p300. Several aspects of this targeting are linked to the ability of SB203580 to inhibit p38 MAPK-controlled pathways. Together, these results provide the molecular basis through which the combinatorial structure and context of the composite elements of the IL-2 promoter dictates mitogen responsiveness and drug susceptibility that are quantitatively and qualitatively distinct from the isolated action of single consensus sequences and/or transcriptional motifs.
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Affiliation(s)
- James L Smith
- Advanced Technology Center, Laboratory of Receptor Biology and Gene Expression, NCI, National Institutes of Health, Bethesda, Maryland 20892-4605, USA
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Ayroldi E, Zollo O, Macchiarulo A, Di Marco B, Marchetti C, Riccardi C. Glucocorticoid-induced leucine zipper inhibits the Raf-extracellular signal-regulated kinase pathway by binding to Raf-1. Mol Cell Biol 2002; 22:7929-41. [PMID: 12391160 PMCID: PMC134721 DOI: 10.1128/mcb.22.22.7929-7941.2002] [Citation(s) in RCA: 137] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Glucocorticoid-induced leucine zipper (GILZ) is a leucine zipper protein, whose expression is augmented by dexamethasone (DEX) treatment and downregulated by T-cell receptor (TCR) triggering. Stable expression of GILZ in T cells mimics some of the effects of glucocorticoid hormones (GCH) in GCH-mediated immunosuppressive and anti-inflammatory activity. In fact, GILZ overexpression inhibits TCR-activated NF-kappaB nuclear translocation, interleukin-2 production, FasL upregulation, and the consequent activation-induced apoptosis. We have investigated the molecular mechanism underlying GILZ-mediated regulation of T-cell activation by analyzing the effects of GILZ on the activity of mitogen-activated protein kinase (MAPK) family members, including Raf, MAPK/extracellular signal-regulated kinase (ERK) 1/2 (MEK-1/2), ERK-1/2, and c-Jun NH(2)-terminal protein kinase (JNK). Our results indicate that GILZ inhibited Raf-1 phosphorylation, which resulted in the suppression of both MEK/ERK-1/2 phosphorylation and AP-1-dependent transcription. We demonstrate that GILZ interacts in vitro and in vivo with endogenous Raf-1 and that Raf-1 coimmunoprecipitated with GILZ in murine thymocytes treated with DEX. Mapping of the binding domains and experiments with GILZ mutants showed that GILZ binds the region of Raf interacting with Ras through the NH(2)-terminal region. These data suggest that GILZ contributes, through protein-to-protein interaction with Raf-1 and the consequent inhibition of Raf-MEK-ERK activation, to regulating the MAPK pathway and to providing a further mechanism underlying GCH immunosuppression.
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Affiliation(s)
- Emira Ayroldi
- Department of Clinical and Experimental Medicine, Section of Pharmacology. Department of Drug Chemistry and Technology, University of Perugia, 06100 Perugia, Italy
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38
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Li J, Huang B, Shi X, Castranova V, Vallyathan V, Huang C. Involvement of hydrogen peroxide in asbestos-induced NFAT activation. Mol Cell Biochem 2002; 234-235:161-8. [PMID: 12162429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
The present study investigated the role of reactive oxygen species (ROS) in activation of nuclear factor of activated T cells (NFAT), a pivotal transcription factor responsible for regulation of cytokines, by asbestos in mouse embryo fibroblast PW cells. Exposure of cells to asbestos led to the transactivation of NFAT in a time- and dose-dependent manner. Scavenging of asbestos-induced H2O2 with N-acety-L-cyteine (NAC, a general antioxidant) or catalase (a specific H2O2 inhibitor) resulted in inhibition of NFAT activation. In contrast, an increase in H2O2 generation by the addition of superoxide dismutase (SOD) slightly enhanced asbestos-induced NFAT activation. In addition, pretreatment of cells with sodium formate did not exhibit any inhibition of NFAT activity induced by asbestos. These results demonstrated that H2O2 appeared to play an important role in asbestos-induced NFAT transactivation. Furthermore, it was observed that incubation of cells with 12-O-tetradecanoylphorbol-13-acetate (TPA) not only resulted in NFAT activation by itself, but also enhanced asbestos-induced NFAT induction. Pretreatment of cells with cyclosporin A (CSA), a pharmacological inhibitor of the phosphatase calcineurin, blocked both asbestos- and TPA plus asbestos-induced NFAT activation. These data suggest that asbestos is able to induce NFAT activation through H2O2-dependent and CSA-sensitive pathways, which may be involved in asbestos-induced carcinogenesis.
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Affiliation(s)
- Jingxia Li
- Nelson Institute of Environmental Medicine, New York University School of Medicine, Tuxedo 10987, USA
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Tanaka M, Ueda A, Kanamori H, Ideguchi H, Yang J, Kitajima S, Ishigatsubo Y. Cell-cycle-dependent regulation of human aurora A transcription is mediated by periodic repression of E4TF1. J Biol Chem 2002; 277:10719-26. [PMID: 11790771 DOI: 10.1074/jbc.m108252200] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Human aurora A is a serine-threonine kinase that controls various mitotic events. The transcription of aurora A mRNA varies throughout the cell cycle and peaks during G(2)/M. To clarify the transcriptional mechanism, we first cloned the 1.8-kb 5'-flanking region of aurora A including the first exon. Transient expression of aurora A promoter-luciferase constructs containing a series of 5'-truncated sequences or site-directed mutations identified a 7-bp sequence (CTTCCGG) from -85 to -79 as a positive regulatory element. Electromobility shift assays identified the binding of positive regulatory proteins to the CTTCCGG element. Anti-E4TF1-60 antibody generated a supershifted complex. Furthermore, coexpression of E4TF1-60 and E4TF1-53 markedly increased aurora A promoter activity. Synchronized cells transfected with the aurora A promoter-luciferase constructs revealed that the promoter activity of aurora A increased in the S phase and peaked at G(2)/M. In addition, we identified a tandem repressor element, CDE/CHR, just downstream of the CTTCCGG element, and mutation within this element led to a loss of cell cycle regulation. We conclude that the transcription of aurora A is positively regulated by E4TF1, a ubiquitously expressed ETS family protein, and that the CDE/CHR element was essential for the G(2)/M-specific transcription of aurora A.
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Affiliation(s)
- Masatsugu Tanaka
- First Department of Internal Medicine, Yokohama City University School of Medicine, Yokohama 236-0004, Japan
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Yoh K, Sugawara T, Motohashi H, Takahama Y, Koyama A, Yamamoto M, Takahashi S. Transgenic over-expression of MafK suppresses T cell proliferation and function in vivo. Genes Cells 2001; 6:1055-66. [PMID: 11737266 DOI: 10.1046/j.1365-2443.2001.00489.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND The small Maf proteins regulate gene transcription from Maf recognition elements (MARE). These proteins do not contain a canonical transactivation domain. Depending upon the ratio of small Maf proteins to their partner proteins, which either possess a transactivation domain or not, transcription can be switched on or off. RESULTS Transgenic mice were generated which over-express the small Maf family member MafK, specifically in the T cell lineage. It was our expectation that the high level of MafK would shift the balance to the formation of MafK homodimer and thereby repress MARE-dependent transcription. The transgenic mice had a shortened life span because of Pneumocystis carinii pneumonia and displayed a decrease in thymocytes and lower IL-2 and IL-4 mRNA expression levels. Analyses by electrophoretic gel mobility shift assay revealed that over-expressed MafK could interact with the proximal AP-1 sequence of IL-2 and the MARE in the IL-4 promoter region. CONCLUSION These results indicate that when over-expressed, MafK binds to a MARE-like sequence and represses MARE-dependent transcription. Consequently, T cell proliferation and cytokine secretion are affected. The MafK homodimer serves as an important molecular probe for evaluating the role played by cis-acting MAREs in the proliferation and function of T cells.
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Affiliation(s)
- K Yoh
- Institute of Basic Medical Sciences, University of Tsukuba, Tsukuba 305-8575, Japan
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Huang C, Ding M, Li J, Leonard SS, Rojanasakul Y, Castranova V, Vallyathan V, Ju G, Shi X. Vanadium-induced nuclear factor of activated T cells activation through hydrogen peroxide. J Biol Chem 2001; 276:22397-403. [PMID: 11292823 DOI: 10.1074/jbc.m010828200] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The present study investigated the role of reactive oxygen species (ROS) in activation of nuclear factor of activated T cells (NFAT), a pivotal transcription factor responsible for regulation of cytokines, by vanadium in mouse embryo fibroblast PW cells or mouse epidermal Cl 41 cells. Exposure of cells to vanadium led to the transactivation of NFAT in a time- and dose-dependent manner. Scavenging of vanadium-induced H(2)O(2) with N-acety-L-cyteine (a general antioxidant) or catalase (a specific H(2)O(2) inhibitor) or the chelation of vanadate with deferoxamine, resulted in inhibition of NFAT activation. In contrast, an increase in H(2)O(2) generation by the addition of superoxide dismutase or NADPH enhanced vanadium-induced NFAT activation. This vanadate-mediated H(2)O(2) generation was verified by both electron spin resonance and fluorescence staining assay. These results demonstrate that H(2)O(2) plays an important role in vanadium-induced NFAT transactivation in two different cell types. Furthermore, pretreatment of cells with nifedipine, a calcium channel blocker, inhibited vanadium-induced NFAT activation, whereas and ionomycin, two calcium ionophores, had synergistic effects with vanadium for NFAT induction. Incubation of cells with cyclosporin A (CsA), a pharmacological inhibitor of the phosphatase calcineurin, blocked vanadium-induced NFAT activation. All data show that vanadium induces NFAT activation not only through a calcium-dependent and CsA-sensitive pathway but also involved H(2)O(2) generation, suggesting that H(2)O(2) may be involved in activation of calcium-calcineurin pathways for NFAT activation caused by vanadium exposure.
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Affiliation(s)
- C Huang
- Nelson Institute of Environmental Medicine, New York University School of Medicine, New York, New York 10016, USA
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Abstract
A plethora of physiological and pathological stimuli induce and activate a group of DNA binding proteins that form AP-1 dimers. These proteins include the Jun, Fos and ATF subgroups of transcription factors. Recent studies using cells and mice deficient in individual AP-1 proteins have begun to shed light on their physiological functions in the control of cell proliferation, neoplastic transformation and apoptosis. Above all such studies have identified some of the target genes that mediate the effects of AP-1 proteins on cell proliferation and death. There is evidence that AP-1 proteins, mostly those that belong to the Jun group, control cell life and death through their ability to regulate the expression and function of cell cycle regulators such as Cyclin D1, p53, p21(cip1/waf1), p19(ARF) and p16. Amongst the Jun proteins, c-Jun is unique in its ability to positively regulate cell proliferation through the repression of tumor suppressor gene expression and function, and induction of cyclin D1 transcription. These actions are antagonized by JunB, which upregulates tumor suppressor genes and represses cyclin D1. An especially important target for AP-1 effects on cell life and death is the tumor suppressor p53, whose expression as well as transcriptional activity, are modulated by AP-1 proteins.
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Affiliation(s)
- E Shaulian
- Laboratory of Gene Regulation and Signal Transduction, Department of Pharmacology, University of California San Diego, 9500 Gilman Drive, La Jolla, California, CA 92093-0636, USA
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Wang X, Li M, Zheng H, Muster T, Palese P, Beg AA, García-Sastre A. Influenza A virus NS1 protein prevents activation of NF-kappaB and induction of alpha/beta interferon. J Virol 2000; 74:11566-73. [PMID: 11090154 PMCID: PMC112437 DOI: 10.1128/jvi.74.24.11566-11573.2000] [Citation(s) in RCA: 439] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The alpha/beta interferon (IFN-alpha/beta) system represents one of the first lines of defense against virus infections. As a result, most viruses encode IFN antagonistic factors which enhance viral replication in their hosts. We have previously shown that a recombinant influenza A virus lacking the NS1 gene (delNS1) only replicates efficiently in IFN-alpha/beta-deficient systems. Consistent with this observation, we found that infection of tissue culture cells with delNS1 virus, but not with wild-type influenza A virus, induced high levels of mRNA synthesis from IFN-alpha/beta genes, including IFN-beta. It is known that transactivation of the IFN-beta promoter depends on NF-kappaB and several other transcription factors. Interestingly, cells infected with delNS1 virus showed high levels of NF-kappaB activation compared with those infected with wild-type virus. Expression of dominant-negative inhibitors of the NF-kappaB pathway during delNS1 virus infection prevented the transactivation of the IFN-beta promoter, demonstrating a functional link between NF-kappaB activation and IFN-alpha/beta synthesis in delNS1 virus-infected cells. Moreover, expression of the NS1 protein prevented virus- and/or double-stranded RNA (dsRNA)-mediated activation of the NF-kappaB pathway and of IFN-beta synthesis. This inhibitory property of the NS1 protein of influenza A virus was dependent on its ability to bind dsRNA, supporting a model in which binding of NS1 to dsRNA generated during influenza virus infection prevents the activation of the IFN system. NS1-mediated inhibition of the NF-kappaB pathway may thus play a key role in the pathogenesis of influenza A virus.
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Affiliation(s)
- X Wang
- Department of Microbiology, Mount Sinai School of Medicine, New York, New York 10029, USA
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44
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Czyzyk J, Leitenberg D, Taylor T, Bottomly K. Combinatorial effect of T-cell receptor ligation and CD45 isoform expression on the signaling contribution of the small GTPases Ras and Rap1. Mol Cell Biol 2000; 20:8740-7. [PMID: 11073975 PMCID: PMC86498 DOI: 10.1128/mcb.20.23.8740-8747.2000] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
By using ligands with various affinities for the T-cell receptor (TCR) and by altering the contribution of the CD45 tyrosine phosphatase, the effects of the potency of TCR-induced signals on the function of small GTPases Ras and Rap1 were studied. T cells expressing low-molecular-weight CD45 isoforms (e.g., CD45RO) exhibited the strongest activation of the Ras-dependent Elk-1 transcription factor and the highest sensitivity to the inhibitory action of dominant negative mutant Ras compared to T cells expressing high-molecular-weight CD45 isoforms (ABC). Moreover, stimulation of CD45RO(+), but not CD45ABC(+), T cells with a high-affinity TCR ligand induced suboptimal Elk-1 activation compared with the stimulation induced by an intermediate-affinity TCR-ligand interaction. This observation suggested that the Ras-dependent signaling pathway is safeguarded in CD45RO(+) expressors by a negative regulatory mechanism(s) which prohibits maximal activation of the Ras-dependent signaling events following high-avidity TCR-ligand engagement. Interestingly, the biochemical activity of another small GTPase, the Ras-like protein Rap1, which has been implicated in the functional suppression of Ras signaling, was inversely correlated with the extent of Elk-1 activation induced by different-affinity TCR ligands. Consistently, overexpression of putative Rap dominant negative mutant RapN17 or the physiologic inhibitor of Rap1, the Rap GTPase-activating protein RapGAP, augmented the Elk-1 response in CD45RO(+) T cells. This is in contrast to the suppressive effect of RapN17 and RapGAP on CD45ABC(+) T cells, underscoring the possibility that Rap1 can act as either a repressor or a potentiator of Ras effector signals, depending on CD45 isoform expression. These observations suggest that cells expressing distinct isoforms of CD45 employ different signal transduction schemes to optimize Ras-mediated signal transduction in activated T lymphocytes.
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Affiliation(s)
- J Czyzyk
- Section of Immunobiology, Yale University School of Medicine, New Haven, Connecticut 06510, USA
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45
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Serfling E, Berberich-Siebelt F, Chuvpilo S, Jankevics E, Klein-Hessling S, Twardzik T, Avots A. The role of NF-AT transcription factors in T cell activation and differentiation. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1498:1-18. [PMID: 11042346 DOI: 10.1016/s0167-4889(00)00082-3] [Citation(s) in RCA: 156] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The family of genuine NF-AT transcription factors consists of four members (NF-AT1 [or NF-ATp], NF-AT2 [or NF-ATc], NF-AT3 and NF-AT4 [or NF-ATx]) which are characterized by a highly conserved DNA binding domain (is designated as Rel similarity domain) and a calcineurin binding domain. The binding of the Ca(2+)-dependent phosphatase calcineurin to this region controls the nuclear import and exit of NF-ATs. This review deals (1) with the structure of NF-AT proteins, (2) the DNA binding of NF-AT factors and their interaction with AP-1, (3) NF-AT target genes, (4) signalling pathways leading to NF-AT activation: the role of protein kinases and calcineurin, (5) the nuclear entry and exit of NF-AT factors, (6) transcriptional transactivation by NF-AT factors, (7) the structure and expression of the chromosomal NF-AT2 gene, and (8) NF-AT factors in Th cell differentiation. The experimental data presented and discussed in the review show that NF-AT factors are major players in the control of T cell activation and differentiation and, in all likelihood, also of the cell cycle and apoptosis of T lymphocytes.
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Affiliation(s)
- E Serfling
- Department of Molecular Pathology, Institute of Pathology, University of Würzburg, Josef-Schneider-Str. 2, D-97080 Würzburg, Germany.
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Huang C, Mattjus P, Ma WY, Rincon M, Chen NY, Brown RE, Dong Z. Involvement of nuclear factor of activated T cells activation in UV response. Evidence from cell culture and transgenic mice. J Biol Chem 2000; 275:9143-9. [PMID: 10734048 PMCID: PMC2652749 DOI: 10.1074/jbc.275.13.9143] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Mammalian cells respond to UV radiation by signaling cascades leading to activation of transcription factors, such as activated protein 1, NFkappaB, and p53, a process known as the "UV response." Nuclear factor of activated T cells (NFAT) was first identified as an inducible nuclear factor in immune response and subsequently found to be expressed in other tissues and cells. To date, however, the regulation and function of NFAT in tissues and cells, other than the immune system, are not well understood. In this study, we demonstrate that UV radiation activates NFAT-dependent transcription through a calcium-dependent mechanism in mouse epidermal JB6 cell lines, as well as in the skin of NFAT-luciferase reporter transgenic mice. Exposure of JB6 cells to UV radiation leads to the transactivation of NFAT in a dose-dependent manner. A23187 had a synergistic effect with UV for NFAT induction, whereas pretreatment of cells with nifedipine, a calcium channel blocker, dramatically impaired the NFAT activity induced by either UV or UV plus A23187. Calcium-dependent activation of NFAT by UV was further confirmed by an in vivo study using NFAT-luciferase reporter transgenic mice. These results demonstrated that UV radiation is a strong activator for skin NFAT transactivation through calcium-dependent pathways, suggesting that NFAT activation may be a part of the UV response.
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Affiliation(s)
- Chuanshu Huang
- Hormel Institute, University of Minnesota, Austin, Minnesota 55912
| | - Peter Mattjus
- Hormel Institute, University of Minnesota, Austin, Minnesota 55912
| | - Wei-ya Ma
- Hormel Institute, University of Minnesota, Austin, Minnesota 55912
| | - Mercedes Rincon
- Program in Immunobiology, Department of Medicine, University of Vermont, Burlington, Vermont 05405
| | - Nan-yue Chen
- Hormel Institute, University of Minnesota, Austin, Minnesota 55912
| | | | - Zigang Dong
- Hormel Institute, University of Minnesota, Austin, Minnesota 55912
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Abstract
The vertebrate transcription factor NF-kappaB is induced by over 150 different stimuli. Active NF-kappaB, in turn, participates in the control of transcription of over 150 target genes. Because a large variety of bacteria and viruses activate NF-kappaB and because the transcription factor regulates the expression of inflammatory cytokines, chemokines, immunoreceptors, and cell adhesion molecules, NF-kappaB has often been termed a 'central mediator of the human immune response'. This article contains a complete listing of all NF-kappaB inducers and target genes described to date. The collected data argue that NF-kappaB functions more generally as a central regulator of stress responses. In addition, NF-kappaB activation blocks apoptosis in several cell types. Coupling stress responsiveness and anti-apoptotic pathways through the use of a common transcription factor may result in increased cell survival following stress insults.
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Affiliation(s)
- H L Pahl
- Department of Experimental Anesthesiology, University of Freiburg, 79106 Freiburg, Germany
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Abstract
The vertebrate transcription factor NF-kappaB is induced by over 150 different stimuli. Active NF-kappaB, in turn, participates in the control of transcription of over 150 target genes. Because a large variety of bacteria and viruses activate NF-kappaB and because the transcription factor regulates the expression of inflammatory cytokines, chemokines, immunoreceptors, and cell adhesion molecules, NF-kappaB has often been termed a 'central mediator of the human immune response'. This article contains a complete listing of all NF-kappaB inducers and target genes described to date. The collected data argue that NF-kappaB functions more generally as a central regulator of stress responses. In addition, NF-kappaB activation blocks apoptosis in several cell types. Coupling stress responsiveness and anti-apoptotic pathways through the use of a common transcription factor may result in increased cell survival following stress insults.
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Affiliation(s)
- H L Pahl
- Department of Experimental Anesthesiology, University of Freiburg, 79106 Freiburg, Germany
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Abstract
Interleukin-2 (IL-2) is a growth and differentiation factor critical for clonal T cell expansion and function. Produced exclusively in T cells, IL-2 transcription and synthesis occurs only after appropriate cellular activation via the clonotypic antigen-receptor and co-stimulatory molecules. IL-2 gene expression is initiated by the cooperative binding of different transcription factors and is predominantly controlled at the transcriptional level. Recently, it has been demonstrated that IL-2 transcriptional activity is normally confined to a single, randomly chosen allele. This monoallelic expression of a non-receptor gene product encoded at a non-imprinted, autosomal locus represents an unusual regulatory mode. Although the molecular mechanisms operational for IL-2 transcription have yet to be defined, allele-specific expression of the IL-2 locus constitutes an important expansion to the concept of stochastic gene expression.
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Affiliation(s)
- G A Holländer
- Pediatric Immunology Department of Research and The Children's University Hospital, Hebelstrasse 20, 4031 Basel, Switzerland.
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Matthews JS, O'Neill LA. Distinct roles for p42/p44 and p38 mitogen-activated protein kinases in the induction of IL-2 by IL-1. Cytokine 1999; 11:643-55. [PMID: 10479400 DOI: 10.1006/cyto.1998.0478] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Interleukin 1 (IL-1) activates p42/p44 and p38 mitogen-activated protein kinases (MAP kinases) in target cells. Here we have used two specific inhibitors, PD98059 which inhibits MAP kinase kinase (MEK), and SB203580 which inhibits p38 MAP kinase to explore the involvement of these kinases in the induction of IL-2 by IL-1 in the murine thymoma cell line EL4.NOB-1. Both kinase inhibitors suppressed IL-1-stimulated IL-2 production. PD98059 blocked IL-2 mRNA accumulation and the induction of a reporter gene linked to the IL-2 promoter. In contrast, SB203580 only marginally inhibited IL-2 promoter-linked reporter gene expression and had no inhibitory effect on IL-2 mRNA levels. Neither PD98059 nor SB203580 had an inhibitory effect on NFkappaB-driven reporter gene expression in response to IL-1. Surprisingly, higher concentrations of SB203580 (30 microM) potentiated the IL-1 responses. PD98059 also inhibited induction of IL-2 by phorbol 12-myristate 13-acetate (PMA), and AP1-linked reporter gene expression in response to PMA but not IL-1. These results indicate that p42/p44 MAP kinase is involved in the regulation of IL-2 gene transcription by IL-1, whilst p38 MAP kinase has a post-transcriptional target. Additional IL-1 signalling pathways can clearly compensate for the lack of p38 MAP kinase which result in potentiation of the IL-1 responses observed at high-dose SB203580.
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Affiliation(s)
- J S Matthews
- Department of Biochemistry, Trinity College, Dublin 2, Ireland.
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