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Darlington GJ, Wilson DR, Revel M, Kelly JH. Response of liver genes to acute phase mediators. Ann N Y Acad Sci 2008; 557:310-5; discussion 315-6. [PMID: 2472091 DOI: 10.1111/j.1749-6632.1989.tb24023.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- G J Darlington
- Department of Pathology, Baylor College of Medicine, Houston, Texas 77030
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Radulovic J, Tronson NC. Protein synthesis inhibitors, gene superinduction and memory: too little or too much protein? Neurobiol Learn Mem 2007; 89:212-8. [PMID: 17904877 PMCID: PMC2323246 DOI: 10.1016/j.nlm.2007.08.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2007] [Revised: 08/14/2007] [Accepted: 08/15/2007] [Indexed: 01/11/2023]
Abstract
To date, the effects of protein synthesis inhibitors (PSI) in learning and memory processes have been attributed to translational arrest and consequent inhibition of de novo protein synthesis. Here we argue that amnesia produced by PSI can be the direct result of their abnormal induction of mRNA-a process termed gene superinduction. This action exerted by PSI involves an abundant and prolonged accumulation of mRNA transcripts of genes that are normally transiently induced. We summarize experimental evidence for the multiple mechanisms and signaling pathways mediating gene superinduction and consider its relevance for PSI-induced amnesia. This mechanistic alternative to protein synthesis inhibition is compared to models of electroconvulsive seizures and fragilexsyndrome associated with enhanced mRNA/protein levels and cognitive deficits.
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Affiliation(s)
- Jelena Radulovic
- Department of Psychiatry and Behavioral Sciences, Northwestern University, Feinberg School of Medicine, 303 E Chicago Avenue, Chicago, IL 60611, USA.
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Saito N, Konishi K, Ohta S, Kondo T, Kato M, Hashino S, Takeda H, Asaka M, Ooi HK. Plural light chains in a single plasma cell of a monoclonal gammopathy undetermined significance case: An ultrastructural study. Hum Cell 2007; 20:10-4. [PMID: 17506772 DOI: 10.1111/j.1749-0774.2007.00026.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A 44-year-old man was found to have M-proteins of IgG consisting of kappa- and lambda-chains in serum without lymphadenopathy or splenomegaly. The serum concentrations of IgG, IgA and IgM were within normal limits. Bone marrow examination showed normal cellular marrow containing 6.3% of plasma cells with no abnormal features. No chromosomal abnormality was observed at all. The patient was diagnosed as having monoclonal gammopathy of undetermined significance. The bone marrow plasma cells possessed free kappa- and lambda-chains in Golgi apparatus, rough endoplasmic reticula and cytoplasmic matrices. Plural light chains were simultaneously produced with the same heavy chain in a plasma cell by immunoelectron microscopy. This is the first report in the world of a monoclonal gammopathy of undetermined significance producing plural light chains with the same heavy chain.
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Affiliation(s)
- Nagahito Saito
- Gastroenterology and Hematology Section, Hokkaido University Graduate School of Internal Medicine, Sapporo, Japan.
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Marverti G, Monti MG, Bettuzzi S, Caporali A, Astancolle S, Moruzzi MS. Cisplatin-resistance modulates the effect of protein synthesis inhibitors on spermidine/spermine N(1)-acetyltransferase expression. Int J Biochem Cell Biol 2004; 36:123-37. [PMID: 14592538 DOI: 10.1016/s1357-2725(03)00174-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Cisplatin (DDP)-resistance confers a deficient expression of spermidine/spermine N(1)-acetyltransferase (SSAT) gene in response to the spermine analog N(1),N(12)-bis(ethyl)spermine (BESpm) in the DDP-resistant human ovarian carcinoma cell line (C13*), compared with their parental DDP-sensitive 2008 cells. This SSAT gene deficiency is correlated with a reduced growth sensitivity to spermine analogs. This study was performed to determine whether SSAT gene expression of resistant cells was kept suppressed by labile repressor proteins developed during resistance selection. We show here that inhibitory concentrations of cycloheximide (CHX) and anisomycin (ANISO) differentially affect BESpm-induced SSAT activity in 2008 and in C13* cells in a concentration-dependent manner and allow resistant cells to reach activation levels comparable to those of the sensitive cells. Northern blot analysis revealed that both CHX and ANISO in combination with BESpm caused a synergistic BESpm-mediated accumulation of SSAT mRNA in C13* cells, with respect to each drug alone, while in 2008 cells only a slight increase was observed. The more pronounced effect of inhibitors on the SSAT activity induced by BESpm in the resistant cells was also the result of a more prolonged stabilization of SSAT mRNA and enzyme protein. By contrast, sub-inhibitory concentrations of CHX and ANISO did not significantly stimulate BESpm-induced SSAT transcription and activity. These results suggest that labile repressor proteins, related to DDP-resistance phenotype, play a regulatory role in SSAT gene expression, and further indicate that by overcoming this inhibitory control it is possible to recover BESpm response.
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Affiliation(s)
- Gaetano Marverti
- Dipartimento di Scienze Biomediche, Sezione di Chimica Biologica, Università di Modena e Reggio Emilia, Via Campi 287, 41100, Modena, Italy.
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Juneja HS, Lee S, Thomazy V, Shipley G, Davies PJ. Acute activation of gp130 gene expression in bone marrow stromal cells by contact with myeloma-derived lymphoblastic cell line ARH77 cell membranes. J Interferon Cytokine Res 2001; 21:157-66. [PMID: 11331038 DOI: 10.1089/107999001750133177] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Cell-cell contact of myeloma-derived cell lines (MDCL) or fresh myeloma cells with bone marrow stromal cells (BMSC) is known to induce interleukin-6 (IL-6) and matrix metalloproteinase-1 (MMP-1) production by a marrow stromal cell line. To determine if other BMSC transcripts are altered during cell-cell contact between BMSC and tumor cells, we have used cell lines ARH77 and U266 in an in vitro model. Using mRNA differential display and reverse transcriptase-polymerase chain reaction (RT-PCR), it was determined that a total of 141 transcripts were either upregulated or downregulated in the BMSC on contact with cell membrane from cell lines ARH77 and U266. Induction of two of these transcripts, interleukin-6 (IL-6) and gp130 in the BMSC by ARH77 cell membranes was studied in greater detail. Real-time PCR was used to quantitate transcript levels of gp130, IL-6, and 36b4, a housekeeping gene. Cycloheximide (CHX) alone increased both gp130 and IL-6 transcripts in the BMSC. In addition, CHX caused a superinduction of these transcripts in BMSC exposed to ARH77 cell membranes. The induction of gp130 was independent of the increase in IL-6 mRNA. Upregulation of gp130, a component of the membrane receptors for the IL-6 superfamily, can have profound effects on the response of BMSC to the IL-6 superfamily of cytokines.
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Affiliation(s)
- H S Juneja
- Division of Hematology, Department of Internal Medicine, University of Texas-Houston Medical School, Houston, TX 77030, USA.
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Nilsen EM, Johansen FE, Kvale D, Krajci P, Brandtzaeg P. Different regulatory pathways employed in cytokine-enhanced expression of secretory component and epithelial HLA class I genes. Eur J Immunol 1999; 29:168-79. [PMID: 9933098 DOI: 10.1002/(sici)1521-4141(199901)29:01<168::aid-immu168>3.0.co;2-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The transmembrane secretory component (SC, or pIg receptor) plays a crucial role in mucosal immunity by translocating dimeric IgA and pentameric IgM through exocrine epithelia. This receptor is up-regulated by cytokines in parallel with increased epithelial HLA expression. By use of the human epithelial cell line HT-29m3, we show that IFN-gamma, TNF-alpha and IL-4 activate transcription of the SC gene. This activation was slow, suggesting mediation via newly synthesized protein factors. IFN-gamma and TNF-alpha, but not IL-4, also up-regulated expression of HLA class I genes. However, this gene induction was rapid and did not depend on new protein synthesis. Nuclear run-on experiments showed that the transcription rate of HLA class I genes nearly peaked after only 30 min of IFN-gamma or TNF-alpha stimulation, whereas the SC transcription rate did not peak until after 20-36 h of IFN-gamma, TNF-alpha or IL-4 stimulation. Gel electrophoresis mobility shift assays demonstrated binding of nuclear proteins from cytokine-stimulated HT-29 cells to consensus elements in the promoter of the SC gene, involving the binding site for the nuclear factor-kappaB p50 subunit after TNF-alpha stimulation, and IFN-stimulated response element after IFN-gamma stimulation (and weakly after TNF-alpha. Our observations in vitro likely parallel events in vivo by which activated mucosal T cells and macrophages enhance pIg receptor-mediated external transport of secretory IgA and IgM and up-regulate epithelial HLA expression.
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Affiliation(s)
- E M Nilsen
- Laboratory for Immunohistochemistry and Immunopathology, Institute of Pathology, University of Oslo, The National Hospital, Norway.
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Liu RM, Shi MM, Giulivi C, Forman HJ. Quinones increase gamma-glutamyl transpeptidase expression by multiple mechanisms in rat lung epithelial cells. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 274:L330-6. [PMID: 9530167 DOI: 10.1152/ajplung.1998.274.3.l330] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
gamma-Glutamyl transpeptidase (GGT) plays an important role in glutathione (GSH) metabolism. GGT expression is increased in oxidant-challenged cells; however, the signaling mechanisms involved are uncertain. The present study used 2,3-dimethoxy-1,4-naphthoquinone (DMNQ), a redox cycling quinone that continuously produced H2O2 in rat lung epithelial L2 cells. It was found that DMNQ increased GGT mRNA content by increasing transcription, as measured by nuclear run-on. This was accompanied by increased GGT specific activity. Cycloheximide, a protein synthesis inhibitor, blocked neither the increased GGT mRNA content nor the increased GGT transcription rate caused by DMNQ, suggesting that increased GGT transcription was a direct rather than secondary response. Previous data from this laboratory (R.-M. Liu, H. Hu, T. W. Robinson, and H. J. Forman. Am. J. Respir. Cell Mol. Biol. 14: 186-191, 1996) showed that tert-butylhydroquinone (TBHQ) increased GGT mRNA content by increasing its stability. TBHQ differs markedly from DMNQ in terms of its conjugation with GSH and H2O2 generation. Together, the data suggest that quinones upregulate GGT through multiple mechanisms, increased transcription and posttranscriptional modulation, which are apparently mediated through generation of reactive oxygen species and GSH conjugated formation, respectively.
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Affiliation(s)
- R M Liu
- Department of Molecular Pharmacology and Toxicology, University of Southern California, Los Angeles 90033, USA
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Aoi T, Nakano H, Tanaka Y, Kakiuchi T. Enhancement of antigen-presenting ability of B lymphoma cells by partial inhibition of protein synthesis through inducing B7-1 expression. Immunology 1997; 91:212-8. [PMID: 9227319 PMCID: PMC1363849 DOI: 10.1046/j.1365-2567.1997.00253.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
During the investigation of the role of protein synthesis in antigen-presenting cell (APC) function of A20-HL B lymphoma cells, we found that partial inhibition of protein synthesis enhanced their APC function. The treatment of A20-HL cells with 0.313-2.5 microM emetine, an irreversible inhibitor of protein synthesis, decreased protein synthesis by 60-70%, and enhanced their APC function to stimulate I-Ad/OVA323-339-specific T cells to produce interleukin-2 in response to ovalbumin (OVA). The emetine-treated and paraformaldehyde-fixed A20-HL cells required only 20 nM OVA323-339 peptide to stimulate the T cells, whereas those untreated and fixed required 200 nM peptide. This enhancement of APC function was mostly because of the induction of B7-1 expression on A20-HL cells by the emetine treatment, since B7-1 molecules were detected on the emetine-treated A20-HL cells, but only negligibly, if at all, on the untreated cells, and an anti-B7-1 monoclonal antibody, 1G10, inhibited the enhanced APC function of the emetine-treated A20-HL cells. The emetine-treatment also increased B7-1 mRNA expression in A20-HL cells, suggesting that the induction of B7-1 expression was due to the increase in the accumulation of mRNA and the translation with residual ability to synthesize protein. Thus, partial inhibition of protein synthesis in A20-HL cells increases B7-1 mRNA accumulation and its expression on the cell surface, which results in the enhancement of their APC function.
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Affiliation(s)
- T Aoi
- Department of Immunology, Toho University School of Medicine, Tokyo, Japan
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Faggioli L, Costanzo C, Merola M, Furia A, Palmieri M. Protein synthesis inhibitors cycloheximide and anisomycin induce interleukin-6 gene expression and activate transcription factor NF-kappaB. Biochem Biophys Res Commun 1997; 233:507-13. [PMID: 9144567 DOI: 10.1006/bbrc.1997.6489] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In two human cell lines, MDA-MB-231 and HeLa, the inducible expression of the interleukin-6 (IL-6) gene by two protein synthesis inhibitors, cycloheximide and anisomycin, was compared with the induction by the most potent physiological inducer of IL-6 described to date, interleukin-1beta (IL-1beta). In cycloheximide or anisomycin treated cells, the accumulation of the IL-6 message and the activation of transcription factors required for IL-6 gene expression occurs at an extent similar to that obtained with IL-1beta. Furthermore, IL-6 mRNA accumulation stimulated by cycloheximide or anisomycin is almost completely inhibited in the presence of actinomycin D, indicating that this effect occurs mainly through the activation of the transcriptional machinery. These data indicate that transcriptional induction of the IL-6 gene by inhibitors of protein synthesis is triggered by the same nuclear signals as other inducers.
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Affiliation(s)
- L Faggioli
- Istituto di Chimica Biologica, Universita' di Verona, Italy
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Koromilas AE, Cantin C, Craig AW, Jagus R, Hiscott J, Sonenberg N. The interferon-inducible protein kinase PKR modulates the transcriptional activation of immunoglobulin kappa gene. J Biol Chem 1995; 270:25426-34. [PMID: 7592710 DOI: 10.1074/jbc.270.43.25426] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
PKR is an interferon (IFN)-induced serine/threonine protein kinase that regulates protein synthesis through phosphorylation of eukaryotic translation initiation factor-2 (eIF-2). In addition to its demonstrated role in translational control, recent findings suggest that PKR plays an important role in regulation of gene transcription, as PKR phosphorylates I kappa B alpha upon double-stranded RNA treatment resulting in activation of NF-kappa B DNA binding in vitro (Kumar, A., Haque, J., Lacoste, J., Hiscott, J., and Williams, B.R.G. (1994) Proc. Natl. Acad. Sci. U.S.A. 91, 6288-6292). To further investigate the role of PKR in transcriptional signaling, we expressed the wild type human PKR and a catalytically inactive dominant negative PKR mutant in the murine pre-B lymphoma 70Z/3 cells. Here, we report that expression of wild type PKR had no effect on kappa-chain transcriptional activation induced by lipopolysaccharide or IFN-gamma. However, expression of the dominant negative PKR mutant inhibited kappa gene transcription independently of NF-kappa B activation. Phosphorylation of eIF-2 alpha was not increased by lipopolysaccharide or IFN-gamma, suggesting that PKR mediates kappa gene transcriptional activation without affecting protein synthesis. Our findings further support a transcriptional role for PKR and demonstrate that there are at least two distinct PKR-mediated signal transduction pathways to the transcriptional machinery depending on cell type and stimuli, NF-kappa B-dependent and NF-kappa B-independent.
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Affiliation(s)
- A E Koromilas
- Department of Oncology, McGill University, Montreal, Quebec, Canada
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Onel KB, Tucek-Szabo CL, Ashany D, Lacy E, Nikolic-Zugic J, Elkon KB. Expression and function of the murine CD95/FasR/APO-1 receptor in relation to B cell ontogeny. Eur J Immunol 1995; 25:2940-7. [PMID: 7589095 DOI: 10.1002/eji.1830251034] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Mice defective in Fas-mediated apoptosis (lpr phenotype) have an intrinsic B cell abnormality that predisposes them to autoantibody production. To investigate potential roles for the Fas receptor (FasR) in B cell tolerance, FasR expression and function were evaluated at different stages of B cell development. FasR expression was very low or absent on pro- and pre-B cells, but was detected in early B cell lines and was up-regulated following IFN-gamma-induced maturation of the pre-B cell line 70-Z. Whereas FasR expression was very low in resting mature sIgM+ B cells, expression was markedly increased following mitogen activation and was also elevated in two mature sIgG+ lymphoma lines. FasR expression correlated strongly with the ability of B cells to undergo Fas-mediated apoptosis. In addition, although Fas did not appear to play a direct role in apoptosis mediated by cross-linking of sIg with anti-IgM, anti-FasR and sublethal concentrations of anti-Ig were additive in the induction of apoptosis in the early B cell line WEHI 231. These findings suggest that the Fas pathway is not involved in the elimination of pro- and pre-B cells, but are compatible with an ancillary role for FasR in the elimination of early B cells and elimination of mature B cells following activation.
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Affiliation(s)
- K B Onel
- Specialized Center of Research (SCOR) in SLE, Hospital for Special Surgery-Cornell University Medical Center, New York, NY 10021, USA
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Cohen LY, Courtois G, Parant MA. Differentiation of murine pre-B cell line by an adjuvant muramyl peptide via NF-kappa B activation. Immunobiology 1995; 193:363-77. [PMID: 8522354 DOI: 10.1016/s0171-2985(11)80424-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Muramyl dipeptide (MDP) induces NF-kappa B activation in the murine pre-B cell line 70Z/3, increases the expression of surface immunoglobulins, and potentiates the response to other inducers such as LPS or IL-1. In the present study we investigated whether NF-kappa B activation was related to the MDP-stimulated immunoglobulin expression. In a gel shift assay our results confirmed that MDP but not MDP(D,D), an adjuvant-inactive stereoisomer, could induce a kappa B-binding activity in 70Z/3 cells. The LPS or IL-1 induced NF-kappa B binding activity was increased in the presence of MDP but not of MDP(D,D). A mutant of the cell line called 1.3E2, defective in NF-kappa B activations by LPS, did not respond to MDP. The enhanced surface immunoglobulin expression induced in the wild type 70Z/3 cells by MDP alone or combined to LPS, IL-1 or IFN gamma was not obtained in this variant. The ability of various treatments to activate the kappa gene enhancer was quantitatively evaluated in cells transfected with a kappa-enhancer-luciferase expression plasmid. Treatment of transfected 70Z/3 cells with MDP resulted in a dose-dependent enhancement of luciferase activity, an additive effect to that induced by LPS or IL-1. Treatment of the defective variant transfected with the same construct did not result in luciferase expression after stimulation with the various agents. The transient transfection assays were used to compare the effectiveness of some MDP analogs. Two adjuvant-active compounds unable to enhance kappa light chain expression did not increase the basal response in the transfected 70Z/3 cells, indicating that NF-kappa B activation was not related to the adjuvant potency of MDP but correlated with the kappa induction.
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Affiliation(s)
- L Y Cohen
- Laboratory for Immunological Pharmacology, Pasteur Institute, Paris, France
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Tiedemann H, Tiedemann H, Grunz H, Knöchel W. Molecular mechanisms of tissue determination and pattern formation in amphibian embryos. THE SCIENCE OF NATURE - NATURWISSENSCHAFTEN 1995; 82:123-34. [PMID: 7723850 DOI: 10.1007/bf01177272] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Factors of the TGF-beta superfamily (activin, vegetalizing factor) and the FGF family determine endoderm and mesoderm. The dorsoventral polarity of the mesoderm depends on additional factors (BMP-4, Wnt-8, noggin). Activin can directly activate gene transcription by signal transduction. Mesoderm is determined by factors prelocalized in the marginal zone. Its differentiation depends also on the animal ectoderm. Neural inducing factors have been partially purified. A masked neuralizing factor in the ectoderm is activated by induction of the ectoderm to the nervous system. Phorbolester can evoke neuralization signaling.
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Affiliation(s)
- H Tiedemann
- Institut für Molekularbiologie und Biochemie, Freien Universität, Berlin
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Henkel T, Machleidt T, Alkalay I, Krönke M, Ben-Neriah Y, Baeuerle PA. Rapid proteolysis of I kappa B-alpha is necessary for activation of transcription factor NF-kappa B. Nature 1993; 365:182-5. [PMID: 8371761 DOI: 10.1038/365182a0] [Citation(s) in RCA: 896] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Inducible gene expression in eukaryotes is mainly controlled by the activity of transcriptional activator proteins, such as NF-kappa B (refs 1-3), a factor activated upon treatment of cells with phorbol esters, lipopolysaccharide, interleukin-1 and tumour necrosis factor-alpha. Activation of NF-kappa B involves release of the inhibitory subunit I kappa B from a cytoplasmic complex with the DNA-binding subunits Rel-A (formerly p65) and p50 (refs 6, 7). Cell-free experiments have suggested that protein kinase C and other kinases transfer phosphoryl groups onto I kappa B causing release of I kappa B and subsequent activation of NF-kappa B. Here we report that I kappa B-alpha (formerly MAD-3) is degraded in cells after stimulation with phorbol ester, interleukin-1, lipopolysaccharide and tumour necrosis factor-alpha, an event coincident with the appearance of active NF-kappa B. Treatment of cells with various protease inhibitors or an antioxidant completely prevented the inducible decay of I kappa B-alpha as well as the activation of NF-kappa B. Our findings suggest that the activation of NF-kappa B relies on an inducible degradation of I kappa B-alpha through a cytoplasmic, chymotrypsin-like protease. In intact cells, phosphorylation of I kappa B-alpha is apparently not sufficient for activation of NF-kappa B.
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Affiliation(s)
- T Henkel
- Laboratory for Molecular Biology, Gene Center, Martinsried, Germany
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Paliogianni F, Raptis A, Ahuja SS, Najjar SM, Boumpas DT. Negative transcriptional regulation of human interleukin 2 (IL-2) gene by glucocorticoids through interference with nuclear transcription factors AP-1 and NF-AT. J Clin Invest 1993; 91:1481-9. [PMID: 8473495 PMCID: PMC288123 DOI: 10.1172/jci116353] [Citation(s) in RCA: 165] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
IL-2 gene transcription is affected by several nuclear proteins. We asked whether dexamethasone (Dex) and cyclosporin A (CsA) inhibit IL-2 gene transcription by interfering with the activity of nuclear proteins that bind to the IL-2 promoter. Nuclear extracts from primary human T lymphocytes were analyzed by electrophoretic DNA mobility shift assays. Both Dex and CsA inhibited the binding of transcription factors AP-1 and NF-AT, but not of NF-kB and OCT-1/OAF, to their corresponding sites on the IL-2 gene promoter. To correlate changes in nuclear factor binding in vitro with transcriptional activity in vivo and define the structural requirements for IL-2 promoter repression, we used transient DNA transfections. Jurkat cells were transfected with plasmids containing either the intact IL-2 promoter or its AP-1, NF-AT, and NF-kB motifs. Dex inhibited the IL-2 promoter and the AP-1, but not the NF-AT and NF-kB plasmids. In contrast, CsA inhibited the IL-2 promoter and the NF-AT, but not the AP-1 and NF-kB plasmids. These results suggest that in human T lymphocytes both Dex and CsA inhibited IL-2 gene transcription through interference with transcription factors AP-1 and NF-AT. We propose that, while maximum inhibition may involve interaction with both transcription factors, AP-1 is the primary target of Dex.
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Affiliation(s)
- F Paliogianni
- Kidney Disease Section, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
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Nachtigal M, Nickel B, Cattini P. Pituitary-specific repression of placental members of the human growth hormone gene family. A possible mechanism for locus regulation. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(18)52899-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
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Müller JM, Ziegler-Heitbrock HW, Baeuerle PA. Nuclear factor kappa B, a mediator of lipopolysaccharide effects. Immunobiology 1993; 187:233-56. [PMID: 8330898 DOI: 10.1016/s0171-2985(11)80342-6] [Citation(s) in RCA: 381] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Exposure of certain cell types to bacterial lipopolysaccharide (LPS) leads to activation of nuclear factor kappa B (NF-kappa B), an inducible transcription factor. One of NF-kappa B's unique properties is its posttranslational activation via release of an inhibitory subunit, called inhibitor of NF-kappa B (I kappa B), from a sequestered cytoplasmic form. This event is also triggered under various other conditions of biomedical importance. Other bacterial toxins, tumor necrosis factor-alpha (TNF), interleukin-1 (IL-1), T cell mitogens, UV light, gamma rays and oxidative stress were reported to induce NF-kappa B. The activated form of NF-kappa B, which is rapidly taken up into nuclei, initiates transcription from immediate early genes in a wide variety of cell types. Most of the target genes for NF-kappa B are of relevance for the immune response and can be grouped into those encoding cytokines, cell surface receptors, acute phase proteins and viral genomes, such as that of human immunodeficiency virus type 1 (HIV-1). We will discuss recent experimental evidences suggesting that LPS might share a pathway of NF-kappa B activation with other inducers of the factor. This common pathway may involve reactive oxygen intermediates (ROI) as messenger molecules.
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Affiliation(s)
- J M Müller
- Laboratory for Molecular Biology, Gene Center, Martinsried, Germany
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Abstract
The expression of functional T cell receptor-beta (TCR-beta) transcripts requires the activation of programmed DNA rearrangement events. It is not clear whether other mechanisms dictate TCR-beta mRNA levels during thymic ontogeny. We examined the potential role of RNA splicing as a regulatory mechanism. As a model system, we used an immature T cell clone, SL12.4, that transcribes a fully rearranged TCR-beta gene but essentially lacks mature 1.3-kb TCR-beta transcripts in the cytoplasm. Abundant TCR-beta splicing intermediates accumulate in the nucleus of this cell clone. These splicing intermediates result from inefficient or inhibited excision of four of the five TCR-beta introns; the only intron that is efficiently spliced is the most 5' intron, IVSL. The focal point for the regulation appears to be IVS1C beta 1 and IVS2C beta 1, since unusual splicing intermediates that have cleaved the 5' splice site but not the 3' splice site of these two introns accumulate in vivo. The block in 3' splice site cleavage is of interest since sequence analysis reveals that these two introns possess canonical splice sites. A repressional mechanism involving a labile repressor protein may be responsible for the inhibition of RNA splicing since treatment of SL12.4 cells with the protein synthesis inhibitor cycloheximide reversibly induces a rapid and dramatic accumulation of fully spliced TCR-beta transcripts in the cytoplasm, concomitant with a decline in TCR-beta pre-mRNAs in the nucleus. This inducible system may be useful for future studies analyzing the underlying molecular mechanisms that regulate RNA splicing.
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21
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Qian L, Theodor L, Carter M, Vu MN, Sasaki AW, Wilkinson MF. T cell receptor-beta mRNA splicing: regulation of unusual splicing intermediates. Mol Cell Biol 1993; 13:1686-96. [PMID: 8441406 PMCID: PMC359481 DOI: 10.1128/mcb.13.3.1686-1696.1993] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The expression of functional T cell receptor-beta (TCR-beta) transcripts requires the activation of programmed DNA rearrangement events. It is not clear whether other mechanisms dictate TCR-beta mRNA levels during thymic ontogeny. We examined the potential role of RNA splicing as a regulatory mechanism. As a model system, we used an immature T cell clone, SL12.4, that transcribes a fully rearranged TCR-beta gene but essentially lacks mature 1.3-kb TCR-beta transcripts in the cytoplasm. Abundant TCR-beta splicing intermediates accumulate in the nucleus of this cell clone. These splicing intermediates result from inefficient or inhibited excision of four of the five TCR-beta introns; the only intron that is efficiently spliced is the most 5' intron, IVSL. The focal point for the regulation appears to be IVS1C beta 1 and IVS2C beta 1, since unusual splicing intermediates that have cleaved the 5' splice site but not the 3' splice site of these two introns accumulate in vivo. The block in 3' splice site cleavage is of interest since sequence analysis reveals that these two introns possess canonical splice sites. A repressional mechanism involving a labile repressor protein may be responsible for the inhibition of RNA splicing since treatment of SL12.4 cells with the protein synthesis inhibitor cycloheximide reversibly induces a rapid and dramatic accumulation of fully spliced TCR-beta transcripts in the cytoplasm, concomitant with a decline in TCR-beta pre-mRNAs in the nucleus. This inducible system may be useful for future studies analyzing the underlying molecular mechanisms that regulate RNA splicing.
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Affiliation(s)
- L Qian
- Microbiology and Immunology Department, Vollum Institute for Advanced Biomedical Research, Portland, Oregon
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22
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Mistchenko AS, Diez RA, Romquin N, Sancéau J, Wietzerbin J. Interferon-gamma modulates retinoblastoma gene mRNA in monocytoid cells. Int J Cancer 1993; 53:87-90. [PMID: 8416207 DOI: 10.1002/ijc.2910530117] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
To study the effect of interferon gamma (IFN-gamma) on the expression of the retinoblastoma (RB) susceptibility gene, we performed Northern-blot analysis on RNA extracted from Wish, HEL and monocytoid cell lines U-937 and THP-1 treated with 1,000 IU/ml of recombinant IFN-gamma. In U-937 and THP-1 cells, IFN-gamma increased the abundance of RB mRNA. In Wish and HEL cells, co-treatment with cycloheximide was required for IFN-gamma to increase the level of RB mRNA. Pre-treatment of THP-1 cells with cycloheximide prior to IFN-gamma treatment augmented the effects of IFN-gamma on RB gene expression. The effect of IFN-gamma in THP-1 cells was observed after 3 hr of treatment, being more pronounced after 6 hr and persisting until at least 18 hr, although at a lower level. These results suggest that IFN-gamma regulates the level of RB mRNA by different mechanisms in the different cell types. This cytokine increases the abundance of RB mRNA in monocytoid cell lines, reinforced by prior treatment with cycloheximide. Inhibition of protein synthesis is required in Wish and HEL cell lines before IFN-gamma has an effect on RB gene expression.
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Affiliation(s)
- A S Mistchenko
- Unité INSERM 196, Institut Curie, Section de Biologie, Paris, France
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23
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Tadano T, Otani H, Taira M, Dawid IB. Differential induction of regulatory genes during mesoderm formation in Xenopus laevis embryos. DEVELOPMENTAL GENETICS 1993; 14:204-11. [PMID: 8395366 DOI: 10.1002/dvg.1020140307] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Mesoderm development in Xenopus laevis depends on inductive cell interactions mediated by diffusible molecules. The mesoderm inducer activin is capable of redirecting the development of animal explants both morphologically and biochemically. We have studied the induction of four regulatory genes, Mix. 1, goosecoid (gsc), Xlim-1, and Xbra in such explants by activin, and the influence of other factors on this induction. Activin induction of gsc is strongly enhanced by dorsalization of the embryo by LiCl, while expression of the other genes is only slightly enhanced. The protein synthesis inhibitor cycloheximide (CHX) inhibits the activin-dependent induction of Xbra partially, while induction of Mix. 1 and Xlim-1 is essentially unaffected. In contrast, gsc shows strong superinduction in the presence of activin and CHX, and can be induced in animal explants by CHX alone. Induction and superinduction by CHX have previously been observed for immediate early genes in a variety of systems, notably for the activation of c-fos expression by serum stimulation, but have not been reported in early amphibian embryos.
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Affiliation(s)
- T Tadano
- Laboratory of Molecular Genetics, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20814
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24
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Grilli M, Chiu JJ, Lenardo MJ. NF-kappa B and Rel: participants in a multiform transcriptional regulatory system. INTERNATIONAL REVIEW OF CYTOLOGY 1993; 143:1-62. [PMID: 8449662 DOI: 10.1016/s0074-7696(08)61873-2] [Citation(s) in RCA: 775] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- M Grilli
- Laboratory of Immunology, National Institute for Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
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25
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Maxwell IH, Glode LM, Maxwell F. Expression of diphtheria toxin A-chain in mature B-cells: a potential approach to therapy of B-lymphoid malignancy. Leuk Lymphoma 1992; 7:457-62. [PMID: 1493446 DOI: 10.3109/10428199209049802] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Specifically targeted expression of a toxin gene potentially represents a novel approach to cancer therapy. With a view to the ablation of B-cell malignancies, we have constructed a plasmid, designated pTHA71, which expresses the A-chain of diphtheria toxin (DT-A) with high efficiency and specificity in transfected, mature B-lymphoid cells. The construction incorporated immunoglobulin (Ig) kappa light chain gene regulatory sequences, including a kappa promoter, small intron, partial constant region exon, and 3'-flanking sequence (but lacking a known enhancer). These sequences conferred substantially more efficient expression of DT-A in mature B-cells than was seen from constructs that included only Ig promoters and enhancers. When transfected into the 70Z/3 murine pre-B-cell line, pTHA71 was only expressed efficiently if the cells were induced to express their endogenous, rearranged Ig kappa gene by prior exposure to lipopolysaccharide. The insertion of the enhancer from the Ig kappa large intron into pTHA71, generating pTHA81, did not markedly influence the level of DT-A expression in 70Z/3 cells. The observed absence of expression in pre-B-cells suggests that DT-A constructs similar to pTHA71 might be used for the therapeutic ablation of malignant B-cells of mature stages, while sparing normal progenitor cells.
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Affiliation(s)
- I H Maxwell
- Division of Medical Oncology, University of Colorado Cancer Center, University of Colorado Health Sciences Center, Denver 80262
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26
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Braun J, Saxon A, Wall R, Morrison SL. The second century of the antibody. Molecular perspectives in regulation, pathophysiology, and therapeutic applications. West J Med 1992; 157:158-68. [PMID: 1441467 PMCID: PMC1011237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The modern age of immunology began in 1890 with the discovery of antibodies as a major component of protective immunity. The 2nd century of the antibody begins with a focus on the molecular physiology and pathophysiology of immunoglobulin production. Numerous human variable-region antibody genes have been identified through advances in molecular cloning and anti-variable-region monoclonal antibodies. Some of these variable-region genes are now known to be involved in specific stages of B-lymphocyte differentiation and immune development. This connection has yielded new insights into the pathogenesis of immune dyscrasias and lymphoid neoplasia; common variable immunodeficiency and cryoglobulinemia are highlighted here. The molecular regulation of immunoglobulin expression suggests new targets for pathogenesis and clinical intervention. Finally, genetically engineered antibodies offer novel opportunities for diagnostic and therapeutic applications.
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Affiliation(s)
- J Braun
- Department of Pathology, UCLA School of Medicine 90024-1732
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27
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Lipopolysaccharide-induced NF-kappa B activation in mouse 70Z/3 pre-B lymphocytes is inhibited by mevinolin and 5'-methylthioadenosine: roles of protein isoprenylation and carboxyl methylation reactions. Mol Cell Biol 1992. [PMID: 1729592 DOI: 10.1128/mcb.12.1.103] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
We show that both the lipopolysaccharide (LPS)-induced activation of NF-kappa DNA binding and kappa gene expression are blocked by treating murine pre-B lymphocyte 70Z/3 cells with 5'-methylthioadenosine (MTA), an inhibitor of several S-adenosylmethionine-dependent methylation reactions. We further show that the LPS-induced incorporation of radioactivity from [methyl-3H]methionine into methyl ester-like linkages on a group of membrane polypeptides is also inhibited by MTA treatment, suggesting the involvement of protein methylation reactions in the LPS signal transduction pathway. We also find that NF-kappa B and kappa gene activation in LPS-treated 70Z/3 cells is blocked by mevinolin, an inhibitor that prevents protein isoprenylation. Interestingly, mevinolin-treated cells also exhibited a marked reduction in the methylation of membrane proteins. Neither MTA nor mevinolin significantly inhibited NF-kappa B activation by phorbol myristate acetate, suggesting that these agents act early in signal transduction. These results provide the first evidence that carboxyl methylated and/or isoprenylated proteins play an essential role in the LPS-signaling pathway.
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28
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Law RE, Stimmel JB, Damore MA, Carter C, Clarke S, Wall R. Lipopolysaccharide-induced NF-kappa B activation in mouse 70Z/3 pre-B lymphocytes is inhibited by mevinolin and 5'-methylthioadenosine: roles of protein isoprenylation and carboxyl methylation reactions. Mol Cell Biol 1992; 12:103-11. [PMID: 1729592 PMCID: PMC364073 DOI: 10.1128/mcb.12.1.103-111.1992] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
We show that both the lipopolysaccharide (LPS)-induced activation of NF-kappa DNA binding and kappa gene expression are blocked by treating murine pre-B lymphocyte 70Z/3 cells with 5'-methylthioadenosine (MTA), an inhibitor of several S-adenosylmethionine-dependent methylation reactions. We further show that the LPS-induced incorporation of radioactivity from [methyl-3H]methionine into methyl ester-like linkages on a group of membrane polypeptides is also inhibited by MTA treatment, suggesting the involvement of protein methylation reactions in the LPS signal transduction pathway. We also find that NF-kappa B and kappa gene activation in LPS-treated 70Z/3 cells is blocked by mevinolin, an inhibitor that prevents protein isoprenylation. Interestingly, mevinolin-treated cells also exhibited a marked reduction in the methylation of membrane proteins. Neither MTA nor mevinolin significantly inhibited NF-kappa B activation by phorbol myristate acetate, suggesting that these agents act early in signal transduction. These results provide the first evidence that carboxyl methylated and/or isoprenylated proteins play an essential role in the LPS-signaling pathway.
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Affiliation(s)
- R E Law
- Department of Microbiology and Immunology, University of California, Los Angeles 90024
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29
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Regulation and a possible stage-specific function of Oct-2 during pre-B-cell differentiation. Mol Cell Biol 1991. [PMID: 1922024 DOI: 10.1128/mcb.11.10.4885] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Oct-2 gene appears to encode a developmental regulator of immunoglobulin gene transcription. We demonstrate that the Oct-2 gene is expressed at low levels in a variety of transformed pre-B-cell lines and is induced specifically in these cells by lipopolysaccharide signalling. This work extends an earlier observation in the pre-B-cell line 70Z/3 and therefore suggests that the inducible expression of the Oct-2 gene, like that of the kappa gene, is a characteristic feature of the pre-B stage of B-cell development. In 70Z/3 cells, the lymphokine interleukin-1 also induces the expression of the Oct-2 and kappa loci. Interestingly, expression of the Oct-2 gene is rapidly induced at the transcriptional level and may not require de novo protein synthesis. Since the changes in the activity of the Oct-2 locus completely correlate with the changes of the activity of the kappa locus, the two genes may be transcriptionally regulated by a common trans-acting factor. In 70Z/3 cells, transforming growth factor beta, an inhibitor of kappa-gene induction, blocks the upregulation of Oct-2 but not the activation of NF-kappa B. These results suggest that the combinatorial action of increased levels of Oct-2 and activated NF-kappa B may be necessary for the proper stage-specific expression of the kappa locus.
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30
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Lee TC, Kao SL, Yih LH. Suppression of sodium arsenite-potentiated cytotoxicity of ultraviolet light by cycloheximide in Chinese hamster ovary cells. Arch Toxicol 1991; 65:640-5. [PMID: 1747062 DOI: 10.1007/bf02098029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Post-treatment with sodium arsenite synergistically increased the cytotoxicity of ultraviolet (UV) light. The potentiation of UV cytotoxicity by sodium arsenite was apparently suppressed by cycloheximide (CHM), a protein synthesis inhibitor. The protective effect of CHM against sodium arsenite-potentiated UV cytotoxicity was well correlated to its activity in inhibiting the synthesis of stress proteins, particularly a small polypeptide with a molecular weight of 8500 dalton. This small stress protein was demonstrated as ubiquitin by immunoprecipitation. Our results also showed that neither ubiquitin induction nor potentiation of UV cytotoxicity by post-treatment with sodium arsenite was observed in the stationary cells. Thus, we suggested that ubiquitin is possibly involved in the action of arsenite in potentiating UV-induced cell killing.
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Affiliation(s)
- T C Lee
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan, Republic of China
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31
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Miller CL, Feldhaus AL, Rooney JW, Rhodes LD, Sibley CH, Singh H. Regulation and a possible stage-specific function of Oct-2 during pre-B-cell differentiation. Mol Cell Biol 1991; 11:4885-94. [PMID: 1922024 PMCID: PMC361457 DOI: 10.1128/mcb.11.10.4885-4894.1991] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The Oct-2 gene appears to encode a developmental regulator of immunoglobulin gene transcription. We demonstrate that the Oct-2 gene is expressed at low levels in a variety of transformed pre-B-cell lines and is induced specifically in these cells by lipopolysaccharide signalling. This work extends an earlier observation in the pre-B-cell line 70Z/3 and therefore suggests that the inducible expression of the Oct-2 gene, like that of the kappa gene, is a characteristic feature of the pre-B stage of B-cell development. In 70Z/3 cells, the lymphokine interleukin-1 also induces the expression of the Oct-2 and kappa loci. Interestingly, expression of the Oct-2 gene is rapidly induced at the transcriptional level and may not require de novo protein synthesis. Since the changes in the activity of the Oct-2 locus completely correlate with the changes of the activity of the kappa locus, the two genes may be transcriptionally regulated by a common trans-acting factor. In 70Z/3 cells, transforming growth factor beta, an inhibitor of kappa-gene induction, blocks the upregulation of Oct-2 but not the activation of NF-kappa B. These results suggest that the combinatorial action of increased levels of Oct-2 and activated NF-kappa B may be necessary for the proper stage-specific expression of the kappa locus.
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Affiliation(s)
- C L Miller
- Department of Molecular Genetics and Cell Biology, University of Chicago, Illinois 60637
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32
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Wilkinson MF, Doskow J, von Borstel R, Fong AM, MacLeod CL. The expression of several T cell-specific and novel genes is repressed by trans-acting factors in immature T lymphoma clones. J Exp Med 1991; 174:269-80. [PMID: 1905340 PMCID: PMC2118901 DOI: 10.1084/jem.174.1.269] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Cell surface proteins encoded by members of the immunoglobulin supergene family are sequentially expressed during T cell ontogeny. The molecular mechanisms responsible for the regulation of these surface molecules are not well understood. To investigate this issue, we used a series of well characterized T lymphoma cell clones with phenotypes characteristic of distinct stages of early thymocyte maturation. Somatic cell hybrids formed from these cell lines were employed to detect the presence of negative regulatory molecules. The expression of CD4 and CD8 was strongly repressed in hybrids formed between a CD4+ CD8+ lymphoma clone and "immature" CD4- CD8- lymphoma clones. Individual subunits of the T cell receptor (TCR)/CD3 complex displayed independent regulation in unique patterns in hybrid cells. Hybrids formed by fusing CD3+ and CD3- cells completely repressed CD3-delta mRNA expression while CD3-gamma, -epsilon, and -zeta transcripts were moderately inhibited or codominantly regulated. Similar to CD3-delta, interleukin 2R-alpha(IL-2R-alpha), and TCR-beta mRNA accumulation was trans-negatively regulated. Transcription rate measurements demonstrated that the inhibition of CD4, CD8, CD3-gamma, CD3-epsilon, TCR-beta, and IL-2R-alpha mRNA accumulation in hybrid cells was exerted, at least in part, at the transcriptional level. To test whether repressional regulation is a general feature of T cells, we examined the regulation of six novel genes which were selected solely on the basis of their differential expression between two of the cell lines used in this study. Five of the six novel gene transcripts were repressed in the somatic cell hybrids. Thus, inhibitor factors appear to play a general role in controlling T cell gene expression. The model system presented here may be useful for the identification and characterization of repressor molecules responsible for the regulation of genes expressed during T cell ontogeny.
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MESH Headings
- Animals
- Antigens, Differentiation, T-Lymphocyte/genetics
- Antigens, Surface/genetics
- Blotting, Northern
- CD4 Antigens/genetics
- CD8 Antigens
- Cell Line
- Cell Nucleus/physiology
- Clone Cells
- DNA Probes
- Flow Cytometry
- Fluorescent Antibody Technique
- Gene Expression Regulation, Neoplastic
- Hybrid Cells
- Lymphoma, T-Cell/genetics
- Lymphoma, T-Cell/immunology
- Mice
- RNA, Messenger/genetics
- RNA, Neoplasm/genetics
- RNA, Neoplasm/isolation & purification
- Receptors, Interleukin-2/genetics
- T-Lymphocytes/immunology
- Transcription, Genetic
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Affiliation(s)
- M F Wilkinson
- Vollum Institute for Advanced Biomedical Research and Microbiology Department, Oregon Health Sciences University, Portland 97201
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33
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Interleukin-6 signals activating junB and TIS11 gene transcription in a B-cell hybridoma. Mol Cell Biol 1991. [PMID: 1705005 DOI: 10.1128/mcb.11.3.1409] [Citation(s) in RCA: 95] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The events in interleukin-6 (IL-6) signal transduction leading to primary response gene activation were analyzed in murine B-cell hybridoma and plasmacytoma cells which require IL-6 for growth. IL-6 stimulation of IL-6-deprived cells resulted in the rapid and transient tyrosine phosphorylation of a 160-kDa cellular protein (p160). This was followed by the highly selective induction of two primary response genes, junB/AP-1 transcription factor and TIS11. junB and TIS11 inductions were unaffected by cycloheximide, suggesting that posttranslational modifications accounted for their activation. Activation of junB and TIS11 transcription required rapid tyrosine kinase activity as well as a different protein kinase activity sensitive to the potent kinase inhibitor, H7, and activated following p160 tyrosine phosphorylation. This H7-sensitive kinase appears to be distinct from any well-characterized protein kinase-second messenger system. On the basis of these findings, we propose that IL-6-induced signal transduction proceeds through a novel protein kinase cascade which activates junB and TIS11 gene transcription.
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34
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Nakajima K, Wall R. Interleukin-6 signals activating junB and TIS11 gene transcription in a B-cell hybridoma. Mol Cell Biol 1991; 11:1409-18. [PMID: 1705005 PMCID: PMC369414 DOI: 10.1128/mcb.11.3.1409-1418.1991] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The events in interleukin-6 (IL-6) signal transduction leading to primary response gene activation were analyzed in murine B-cell hybridoma and plasmacytoma cells which require IL-6 for growth. IL-6 stimulation of IL-6-deprived cells resulted in the rapid and transient tyrosine phosphorylation of a 160-kDa cellular protein (p160). This was followed by the highly selective induction of two primary response genes, junB/AP-1 transcription factor and TIS11. junB and TIS11 inductions were unaffected by cycloheximide, suggesting that posttranslational modifications accounted for their activation. Activation of junB and TIS11 transcription required rapid tyrosine kinase activity as well as a different protein kinase activity sensitive to the potent kinase inhibitor, H7, and activated following p160 tyrosine phosphorylation. This H7-sensitive kinase appears to be distinct from any well-characterized protein kinase-second messenger system. On the basis of these findings, we propose that IL-6-induced signal transduction proceeds through a novel protein kinase cascade which activates junB and TIS11 gene transcription.
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Affiliation(s)
- K Nakajima
- Department of Microbiology and Immunology, School of Medicine, University of California, Los Angeles 90024
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35
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36
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Kirkland TN, Qureshi N, Takayama K. Diphosphoryl lipid A derived from lipopolysaccharide (LPS) of Rhodopseudomonas sphaeroides inhibits activation of 70Z/3 cells by LPS. Infect Immun 1991; 59:131-6. [PMID: 1898897 PMCID: PMC257716 DOI: 10.1128/iai.59.1.131-136.1991] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Diphosphoryl lipid A derived from nontoxic lipopolysaccharide (LPS) of Rhodopseudomonas sphaeroides ATCC 17023 did not stimulate the murine pre-B cell line 70Z/3 to synthesize surface immunoglobulin or kappa mRNA. However, it effectively blocked Escherichia coli LPS-induced activation of 70Z/3 cells in a concentration-dependent manner. This inhibition was specific only to cells activated by LPS, since it did not inhibit activation of 70Z/3 cells by gamma interferon. Maximal inhibitory effect occurred when the antagonist was added within 2 h before adding the LPS. These results strongly suggested that R. sphaeroides diphosphoryl lipid A is competing with E. coli LPS for physiological lipid A receptors on the 70Z/3 cells.
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Affiliation(s)
- T N Kirkland
- Department of Pathology, University of California, San Diego 92093
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37
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Burrows PD, Kubagawa H, Nishimoto N, Kerr WG, Borzillo GV, Hendershot LM, Cooper MD. Differences in human B cell differentiation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1991; 292:215-26. [PMID: 1950773 DOI: 10.1007/978-1-4684-5943-2_24] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- P D Burrows
- Department of Pediatrics, Medicine and Microbiology University of Alabama, Birmingham
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38
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Interaction of a nuclear protein with a palindromic sequence of the mouse immunoglobulin lambda 2-chain gene promoter is important for its transcription. Mol Cell Biol 1990. [PMID: 2122234 DOI: 10.1128/mcb.10.11.5894] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
By using a gel mobility retardation assay, we detected the formation of three major complexes from the binding of nuclear proteins to the promoter of the immunoglobulin lambda 2-chain gene. Two of the complexes were generated by the presence of an unidentified nuclear factor(s) called herein NF-lambda 2. Although the sequences between lambda 2- and lambda 1-chain gene promoters are very similar, the lambda 1-chain promoter did not compete for the binding of NF-lambda 2 efficiently. The binding site of NF-lambda 2 was localized by DNase I footprinting to a 14-bp region which is about 30 bp upstream of the immunoglobulin octamer motif. This region, referred to as the NF-lambda 2 motif, is within an 18-bp region of twofold rotational symmetry. Experiments with oligomers containing either the NF-lambda 2 or the octamer motifs as competitors for binding and DNase I footprinting, showed that the third complex is the product of the simultaneous binding of an octamer-binding protein and NF-lambda 2. Changing the sequence of the NF-lambda 2 motif to that of the lambda 1-chain counterpart abolished the binding ability of NF-lambda 2. Concomitantly, the level of chloramphenicol acetyltransferase expression driven by the mutated lambda 2 promoter decreased by two- to fivefold when compared with that of the wild-type promoter. It is therefore concluded that the interaction of NF-lambda 2 with the NF-lambda 2 motif stimulates transcription of the lambda 2-chain gene.
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39
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Chang LA, Murialdo H. Interaction of a nuclear protein with a palindromic sequence of the mouse immunoglobulin lambda 2-chain gene promoter is important for its transcription. Mol Cell Biol 1990; 10:5894-902. [PMID: 2122234 PMCID: PMC361381 DOI: 10.1128/mcb.10.11.5894-5902.1990] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
By using a gel mobility retardation assay, we detected the formation of three major complexes from the binding of nuclear proteins to the promoter of the immunoglobulin lambda 2-chain gene. Two of the complexes were generated by the presence of an unidentified nuclear factor(s) called herein NF-lambda 2. Although the sequences between lambda 2- and lambda 1-chain gene promoters are very similar, the lambda 1-chain promoter did not compete for the binding of NF-lambda 2 efficiently. The binding site of NF-lambda 2 was localized by DNase I footprinting to a 14-bp region which is about 30 bp upstream of the immunoglobulin octamer motif. This region, referred to as the NF-lambda 2 motif, is within an 18-bp region of twofold rotational symmetry. Experiments with oligomers containing either the NF-lambda 2 or the octamer motifs as competitors for binding and DNase I footprinting, showed that the third complex is the product of the simultaneous binding of an octamer-binding protein and NF-lambda 2. Changing the sequence of the NF-lambda 2 motif to that of the lambda 1-chain counterpart abolished the binding ability of NF-lambda 2. Concomitantly, the level of chloramphenicol acetyltransferase expression driven by the mutated lambda 2 promoter decreased by two- to fivefold when compared with that of the wild-type promoter. It is therefore concluded that the interaction of NF-lambda 2 with the NF-lambda 2 motif stimulates transcription of the lambda 2-chain gene.
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Affiliation(s)
- L A Chang
- Department of Medical Genetics, University of Toronto, Ontario, Canada
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40
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Otani Y, Quinones S, Saus J, Kurkinen M, Harris ED. Cycloheximide induces stromelysin mRNA in cultured human fibroblasts. EUROPEAN JOURNAL OF BIOCHEMISTRY 1990; 192:75-9. [PMID: 2169419 DOI: 10.1111/j.1432-1033.1990.tb19197.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Stromelysin is a metalloproteinase that degrades extracellular matrix macromolecules including fibronectin, laminin, collagen IV and proteoglycans. We now report that cycloheximide, an inhibitor of protein synthesis, induces human stromelysin mRNA in fibroblast cultures in a time- and dose-dependent fashion. As determined by Northern hybridization, a 24-h treatment with cycloheximide increased stromelysin mRNA about 20-fold over the control level. In vitro translation or translation in cells after removal of cycloheximide resulted in increased levels of immunoprecipitable stromelysin suggesting that the cycloheximide-induced stromelysin mRNA was functional. Analysis of mRNA stability suggested that the cycloheximide effect is in part due to the increased activation of the stromelysin gene. In contrast to these results, cycloheximide did not induce collagenase mRNA but, rather, prevented its induction by interleukin-1 beta. These data provide evidence for discoordinate regulation of collagenase and stromelysin genes and suggest that a short-lived repressor protein may play a role in the stromelysin gene expression.
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Affiliation(s)
- Y Otani
- Department of Medicine, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Piscataway 08854
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41
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Erselius JR, Jostes B, Hatzopoulos AK, Mosthaf L, Gruss P. Cell-type-specific control elements of the lymphotropic papovavirus enhancer. J Virol 1990; 64:1657-66. [PMID: 2319649 PMCID: PMC249302 DOI: 10.1128/jvi.64.4.1657-1666.1990] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Lymphotropic papovavirus (LPV) exhibits a highly restricted host range, in which only cells of primate B-lymphocyte origin are permissive for infection. Its enhancer element contributes to this tropism, since transcriptional potentiation is confined to cells of the hematopoietic lineage. Nuclear extracts from B and T cells, but not from HeLa cells, contain protein factors that interact specifically with the LPV 63-base-pair enhancer repeat, as demonstrated by DNase I footprinting and gel retardation experiments. Within the repeat three sequence motifs were identified: the core motif, the Pu box, and a novel element named T motif. Functional analysis demonstrated that these motifs as well as some sequences upstream of the repeat contribute to the optimal activity of the enhancer. There are clear differences between the patterns of binding of the B and T lymphocyte nuclear proteins to the enhancer which are also reflected in the transcriptional activity of the enhancer in both cell types. Furthermore, the activity of the LPV enhancer and its interaction with nuclear proteins seem to be regulated during B-cell differentiation.
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Affiliation(s)
- J R Erselius
- Department of Molecular Cell Biology, Max-Planck-Institute of Biophysical Chemistry, Göttingen, Federal Republic of Germany
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42
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Ikeda K, Lu C, Weir EC, Mangin M, Broadus AE. Regulation of parathyroid hormone-related peptide gene expression by cycloheximide. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)39372-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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43
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Nelms K, Hromas R, Van Ness B. Identification of a second inducible DNA-protein interaction in the kappa immunoglobulin enhancer. Nucleic Acids Res 1990; 18:1037-43. [PMID: 2107525 PMCID: PMC330361 DOI: 10.1093/nar/18.4.1037] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Control of kappa immunoglobulin light-chain gene expression requires the interaction of tissue specific and developmentally regulated DNA-binding proteins with the kappa gene enhancer. Deletion of enhancer sequences upstream from the NF-kB binding site has been shown to impair enhancer function, implying additional proteins may interact with these sequences. In surveying this region for sites of protein binding, a novel DNA-protein interaction, designated kBF-A, was detected. The binding activity of this factor appears to be specific to activated pre-B cells and correlates with high level induction of kappa transcription in these cells.
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Affiliation(s)
- K Nelms
- Institute of Human Genetics, University of Minnesota, Minneapolis 55455
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44
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Duclert A, Piette J, Changeux JP. Induction of acetylcholine receptor alpha-subunit gene expression in chicken myotubes by blocking electrical activity requires ongoing protein synthesis. Proc Natl Acad Sci U S A 1990; 87:1391-5. [PMID: 2304905 PMCID: PMC53481 DOI: 10.1073/pnas.87.4.1391] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The level of acetylcholine receptor alpha-subunit mRNA in primary cultures of chicken myotubes increases when the spontaneous electrical activity of the myotube is suppressed by the sodium channel blocker tetrodotoxin. This increase was prevented by two translational inhibitors: cycloheximide and anisomycin. Neither the basal level of alpha-subunit mRNA nor that of muscle-specific creatine phosphokinase mRNA was affected by these inhibitors. In contrast, cycloheximide potentiated the limited increase of alpha-subunit mRNA levels evoked by the neuropeptide calcitonin gene-related peptide. The high level of alpha-subunit mRNA elicited by tetrodotoxin treatment did not persist after subsequent addition of cycloheximide in the presence of tetrodotoxin, indicating that the continuous synthesis of protein factor(s) is necessary for this regulation. Moreover, cycloheximide decreased the high level of alpha-subunit mRNA present at early stages of in vitro maturation of muscle primary cultures without blocking the further increase of the muscle-specific creatine phosphokinase mRNA. Implications of the requirement for constant synthesis of protein factors on the induction of muscle-specific gene expression by blocking myotube electrical activity are discussed.
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Affiliation(s)
- A Duclert
- Département des Biotechnologies, Institut Pasteur, Paris, France
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45
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Lipopolysaccharide-unresponsive mutant pre-B-cell lines blocked in NF-kappa B activation. Mol Cell Biol 1990. [PMID: 2104663 DOI: 10.1128/mcb.10.1.422] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
NF-kappa B activation is a crucial late step in the induction of immunoglobulin kappa light-chain gene expression in pre-B cells by lipopolysaccharide (LPS). We have analyzed NF-kappa B activation in three independent mutant lines of 70Z/3 pre-B cells which are unresponsive to LPS. All three variant cell lines failed to activate NF-kappa B when induced with LPS or the phorbol ester 12-O-tetradecanoylphorbol 13-acetate. However, all three cell lines contained functional NF-kappa B, as revealed by detergent treatment of cytoplasmic extracts. Moreover, cycloheximide induced limited activation of NF-kappa B comparable to that in wild-type 70Z/3 pre-B cells in two of the three variant lines. These results indicate that the mutations blocking kappa gene induction in these variant 70Z/3 pre-B-cell lines affect NF-kappa B activation.
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46
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Affiliation(s)
- P W Kincade
- Immunobiology and Cancer Program, Oklahoma Medical Research Foundation, Oklahoma City 73104
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47
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Leighton JD, Pfeilschifter J. Interleukin 1- and tumor necrosis factor-stimulation of prostaglandin E2 synthesis in MDCK cells, and potentiation of this effect by cycloheximide. FEBS Lett 1990; 259:289-92. [PMID: 2294017 DOI: 10.1016/0014-5793(90)80029-i] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The effects of interleukin (IL)-1 alpha, IL-1 beta and TNF alpha on prostaglandin-E2 synthesis in Madin-Darby canine kidney (MDCK) cells were investigated. IL-1 beta time- and dose-dependently stimulated prostaglandin-E2 synthesis. While TNF alpha produced a comparatively small but significant stimulation of PGE2 release, coincubation of IL-1 beta with TNF alpha produced a marked synergistic stimulation of PGE2 release. The effect of IL-1 beta and of IL-1 beta and TNF alpha was apparent as early as after 2 h of incubation. The enhanced PGE2 synthesis was inhibited by indomethacin as well as actinomycin D, while cycloheximide surprisingly potentiated PGE2 synthesis in response to both IL-1 beta and TNF alpha. IL-1 alpha alone was ineffective in stimulating a significant release of PGE2 at concentrations as high as 10 nM. However, it also showed a marked synergistic interaction with TNF alpha in stimulating PGE2 release.
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Affiliation(s)
- J D Leighton
- Research Department, Ciba-Geigy AG, Basel, Switzerland
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48
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Briskin M, Damore M, Law R, Lee G, Kincade PW, Sibley CH, Kuehl M, Wall R. Lipopolysaccharide-unresponsive mutant pre-B-cell lines blocked in NF-kappa B activation. Mol Cell Biol 1990; 10:422-5. [PMID: 2104663 PMCID: PMC360774 DOI: 10.1128/mcb.10.1.422-425.1990] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
NF-kappa B activation is a crucial late step in the induction of immunoglobulin kappa light-chain gene expression in pre-B cells by lipopolysaccharide (LPS). We have analyzed NF-kappa B activation in three independent mutant lines of 70Z/3 pre-B cells which are unresponsive to LPS. All three variant cell lines failed to activate NF-kappa B when induced with LPS or the phorbol ester 12-O-tetradecanoylphorbol 13-acetate. However, all three cell lines contained functional NF-kappa B, as revealed by detergent treatment of cytoplasmic extracts. Moreover, cycloheximide induced limited activation of NF-kappa B comparable to that in wild-type 70Z/3 pre-B cells in two of the three variant lines. These results indicate that the mutations blocking kappa gene induction in these variant 70Z/3 pre-B-cell lines affect NF-kappa B activation.
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Affiliation(s)
- M Briskin
- Molecular Biology Institute, University of California School of Medicine, Los Angeles 90024
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49
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Sambucetti LC, Cherrington JM, Wilkinson GW, Mocarski ES. NF-kappa B activation of the cytomegalovirus enhancer is mediated by a viral transactivator and by T cell stimulation. EMBO J 1989; 8:4251-8. [PMID: 2556267 PMCID: PMC401626 DOI: 10.1002/j.1460-2075.1989.tb08610.x] [Citation(s) in RCA: 219] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The expression of cytomegalovirus alpha (immediate early) genes is under control of an enhancer that carries signals for strong constitutive expression as well as response elements for transactivation by viral proteins. We have used synthetic oligonucleotides representing the 16, 18 and 19 bp repeat elements within the enhancer to investigate the role of virus-induced cellular transcription factors in enhancer activation. We show that the transcription factor NF-kappa B, which binds to the 18 bp repeat, plays a central role in enhancer activation in infected human fibroblasts and that activation is mediated by the product of the viral gene ie1. The simian immunodeficiency virus kappa B site can functionally substitute for the 18 bp element in transient transactivation assays and can also compete efficiently for specific binding to the 18 bp repeat element in vitro. Point mutations in the NF-kappa B site within the 18 bp element disrupt ie1-mediated transactivation and binding. We have found that the characteristics of the 18 bp binding factor from human fibroblasts are indistinguishable from NF-kappa B induced by phorbol ester plus mitogen treatment of T lymphocytes, as determined by gel mobility shift assay as well as protection of the binding site from chemical cleavage. Furthermore, T cell stimulation mediates activation of the viral enhancer via kappa B sites, an observation that may be important in the interaction of cytomegalovirus with the naturally infected human host. Thus, NF-kappa B plays a central role as a target for enhancer activation via viral and cellular factors.
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Affiliation(s)
- L C Sambucetti
- Department of Microbiology and Immunology, Stanford University School of Medicine, CA 94305
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50
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Hermanson GG, Briskin M, Sigman D, Wall R. Immunoglobulin enhancer and promoter motifs 5' of the B29 B-cell-specific gene. Proc Natl Acad Sci U S A 1989; 86:7341-5. [PMID: 2508087 PMCID: PMC298057 DOI: 10.1073/pnas.86.19.7341] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
B29 is a B-cell-specific member of the immunoglobulin gene superfamily that is expressed throughout B-cell development beginning with the earliest precursor B cells undergoing immunoglobulin heavy-chain gene segment rearrangements. We have analyzed the region upstream of the B29 gene to identify DNA sequences involved in transcriptional regulation of this gene. The B29 gene lacks a TATA box and transcription is initiated at multiple sites. The B29 gene sequence 5' of these transcription start sites contains six promoter and enhancer motifs known to control immunoglobulin gene transcription. The most notable is a perfect octamer (5'-ATTTGCAT-3'), which binds the Oct-2 B-cell-specific transcription factor and thereby can account for the tissue-specific expression of this gene.
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Affiliation(s)
- G G Hermanson
- Molecular Biology Institute, University of California, Los Angeles 90024
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