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Sailer A, Nagata K, Näf D, Aebi M, Weissmann C. Interferon regulatory factor-1 (IRF-1) activates the synthetic IRF-1-responsive sequence (GAAAGT)4 in Saccharomyces cerevisiae. Gene Expr 2018; 2:329-37. [PMID: 1472868 PMCID: PMC6057371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In appropriate mammalian cells, interferon regulatory factor-1 (IRF-1) can activate the virus-responsive element of the IFN-beta promoter (VRE beta") or the synthetic oligonucleotide (GAAAGT)4. The latter contains two copies of the functional equivalent of PRDI, one of the regulatory domains of VRE beta". We prepared yeast strains containing an IRF-1 expression plasmid under the control of the galactose-inducible Gal1 promoter and a reporter plasmid with either (GAAAGT)4, VRE beta", or other test sequences placed upstream of a minimal promoter linked to the beta-galactosidase coding sequence. Upon induction of IRF-1 expression, the (GAAAGT)4-containing promoter was activated, but VRE beta" and all other sequences tested were inactive. Our results showed that IRF-1 belongs to a class of higher eukaryotic transcription factors that can interact with the yeast transcriptional machinery. Our findings also raised the question why the duplicate PRDI-like sequences in (GAAAGT)4 can be activated by IRF-1 synthesized in yeast, but not VRE beta", which also contains at least two PRDI-like sequences.
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Affiliation(s)
- A Sailer
- Institut für Molekularbiologie I, Universität Zürich, Switzerland
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2
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Luo S, Wang Y, Zhao M, Lu Q. The important roles of type I interferon and interferon-inducible genes in systemic lupus erythematosus. Int Immunopharmacol 2016; 40:542-549. [PMID: 27769023 DOI: 10.1016/j.intimp.2016.10.012] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 09/30/2016] [Accepted: 10/14/2016] [Indexed: 12/23/2022]
Abstract
Systemic lupus erythematosus (SLE) is a severe autoimmune disease that causes multiple-organ dysfunction mainly affecting women in their childbearing years. Type I IFN synthesis is usually triggered by viruses, and its production is tightly regulated and limited in time in health individuals. However, many patients with systemic autoimmune diseases including SLE have signs of aberrant production of type I interferon (IFN) and display an increased expression of IFN-inducible genes. Continuous type I IFNs derived from activated plasmacytoid dendritic cells (pDCs) by interferogenic immune complexes (ICs) and migration of these cells to tissues both break immune tolerance and promote an on-going autoimmune reaction in human body. By the means of detecting type I IFNs and IFN-inducible genes, it can help with diagnosis and evaluation of SLE in early stage and more efficiently. Anti-IFN-α monoclonal antibodies in SLE patients were recently reported and is now being investigated in phase II clinical trails. In this review, we focus on recent research progress in type I IFN and IFN-inducible genes. Possible mechanisms behind the dysregulated type I IFN system in SLE and how they contribute to the development of an autoimmune process, and act as a biomarker and therapeutic target will be reviewed.
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Affiliation(s)
- Shuaihantian Luo
- Department of Dermatology, Second Xiangya Hospital of Central South University, Hunan Key Laboratory of Medical Epigenetics, Changsha, Hunan, China
| | - Yunuo Wang
- Department of Endocrinology, Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Ming Zhao
- Department of Dermatology, Second Xiangya Hospital of Central South University, Hunan Key Laboratory of Medical Epigenetics, Changsha, Hunan, China
| | - Qianjin Lu
- Department of Dermatology, Second Xiangya Hospital of Central South University, Hunan Key Laboratory of Medical Epigenetics, Changsha, Hunan, China.
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3
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Tsugawa Y, Kato H, Fujita T, Shimotohno K, Hijikata M. Critical role of interferon-α constitutively produced in human hepatocytes in response to RNA virus infection. PLoS One 2014; 9:e89869. [PMID: 24587086 PMCID: PMC3935935 DOI: 10.1371/journal.pone.0089869] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 01/24/2014] [Indexed: 12/24/2022] Open
Abstract
Several viruses are known to infect human liver and cause the hepatitis, but the interferon (IFN) response, a first-line defense against viral infection, of virus-infected hepatocytes is not clearly defined yet. We investigated innate immune system against RNA viral infection in immortalized human hepatocytes (HuS-E/2 cells), as the cells showed similar early innate immune responses to primary human hepatocytes (PHH). The low-level constitutive expression of IFN-α1 gene, but not IFN-β and IFN-λ, was observed in both PHH and HuS-E/2 cells in the absence of viral infection, suggesting a particular subtype(s) of IFN-α is constitutively produced in human hepatocytes. To examine the functional role of such IFN-α in the antiviral response, the expression profiles of innate immune-related genes were studied in the cells with the treatment of neutralization against type I IFN receptor 2 (IFNAR2) or IFN-α itself to inhibit the constitutive IFN-α signaling before and after virus infection. As the results, a clear reduction of basal level expression of IFN-inducible genes was observed in uninfected cells. When the effect of the inhibition on the cells infected with hepatitis C virus (HCV) was examined, the significant decrease of IFN stimulated gene expression and the enhancement of initial HCV replication were observed, suggesting that the steady-state production of IFN-α plays a role in amplification of antiviral responses to control the spread of RNA viral infection in human hepatocytes.
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Affiliation(s)
- Yoji Tsugawa
- Laboratory of Human Tumor Viruses, Institute for Virus Research, Kyoto University, Kyoto, Japan
- Laboratory of Viral Oncology, Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Hiroki Kato
- Laboratory of Molecular Genetics, Institute for Virus Research, Kyoto University, Kyoto, Japan
| | - Takashi Fujita
- Laboratory of Molecular Genetics, Institute for Virus Research, Kyoto University, Kyoto, Japan
| | - Kunitada Shimotohno
- The Research Center for Hepatitis and Immunology, National Center for Global Health and Medicine, Ichikawa, Japan
| | - Makoto Hijikata
- Laboratory of Human Tumor Viruses, Institute for Virus Research, Kyoto University, Kyoto, Japan
- Laboratory of Viral Oncology, Graduate School of Biostudies, Kyoto University, Kyoto, Japan
- * E-mail:
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4
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Roan F, Inoue N, Offermann MK. Activation of cellular and heterologous promoters by the human herpesvirus 8 replication and transcription activator. Virology 2002; 301:293-304. [PMID: 12359431 DOI: 10.1006/viro.2002.1582] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The key regulator of the switch from latent to lytic replication of the human herpesvirus 8 (HHV-8; KSHV) is the replication and transcription activator (Rta). The ability of Rta to regulate cellular gene expression was examined by transient transfection into cells that were not infected with HHV-8. Rta induced some, but not all, NF-kappa B-responsive reporters through mechanisms that did not involve activation of classic forms of NF-kappa B. Furthermore, transfection of the NF-kappa B subunit Rel A inhibited the ability of Rta to transactivate some but not all reporters. For example, Rel A inhibited the ability of Rta to transactivate the IL-6 promoter, but only when sequences upstream of the NF-kappa B site were present. The ability of Rel A to inhibit Rta-mediated transactivation was not dependent on a functional NF-kappa B site within the promoter, suggesting an indirect mechanism for inhibition. These studies suggest that Rta expression during lytic reactivation of HHV-8 would lead to expression of some cellular genes, including IL-6, whereas activation of NF-kappa B could inhibit some responses to Rta.
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Affiliation(s)
- Florence Roan
- Winship Cancer Institute, Emory University, Atlanta, Georgia 30322, USA
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5
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Audet JF, Masson JY, Rosen GD, Salesse C, Guérin SL. Multiple regulatory elements control the basal promoter activity of the human alpha 4 integrin gene. DNA Cell Biol 1994; 13:1071-85. [PMID: 7702751 DOI: 10.1089/dna.1994.13.1071] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
It has been suggested that expression of the genes encoding the alpha 4/beta 1 integrin increases during wound healing of the cornea. As a first step in understanding the mechanisms required to stimulate alpha 4 gene expression during this process, we defined the minimal upstream sequence required to direct basal promoter activity for this gene. Using deletion analyses of the alpha 4 gene upstream sequence, we identified two functionally important negative regulatory elements. Dimethylsulfate (DMS) methylation interference assays provided evidence for the binding of a single nuclear protein to tandemly repeated homologous cis-acting elements (designated alpha 4.1 and alpha 4.2) from the alpha 4 basal promoter that share the core sequence 5'-GTGGGT-3'. The formation of a protection only at alpha 4.1 in DNase I footprinting suggested that it is the primary target element for the binding of nuclear proteins. Three distinct nuclear proteins bound a double-stranded oligonucleotide bearing the DNA sequence of alpha 4.1 to produce specific DNA-protein complexes (R1 to R3) in gel-shift assays, from which that producing R3 was identified as the protein yielding DNase I protection at alpha 4.1. Detailed mutational analysis of alpha 4.1 and alpha 4.2 indicated that both elements positively regulate gene expression in primary cultures of corneal epithelial cells and Jurkat tissue culture cells, which is consistent with the deletion analysis. However, when transiently transfected into pituitary GH4C1, the alpha 4.2 mutants yielded increased chloramphenicol acetyl transferase activity therefore demonstrating that these elements have the ability to function either as positive or negative regulators of gene transcription in a manner that is dependent on the type of cell transfected.
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Affiliation(s)
- J F Audet
- Unit of Ophthalmology, CHUL Research Center, Ste-Foy, Québec, Canada
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6
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Song Z, Krishna S, Thanos D, Strominger JL, Ono SJ. A novel cysteine-rich sequence-specific DNA-binding protein interacts with the conserved X-box motif of the human major histocompatibility complex class II genes via a repeated Cys-His domain and functions as a transcriptional repressor. J Exp Med 1994; 180:1763-74. [PMID: 7964459 PMCID: PMC2191754 DOI: 10.1084/jem.180.5.1763] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The class II major histocompatibility complex (MHC) molecules function in the presentation of processed peptides to helper T cells. As most mammalian cells can endocytose and process foreign antigen, the critical determinant of an antigen-presenting cell is its ability to express class II MHC molecules. Expression of these molecules is usually restricted to cells of the immune system and dysregulated expression is hypothesized to contribute to the pathogenesis of a severe combined immunodeficiency syndrome and certain autoimmune diseases. Human complementary DNA clones encoding a newly identified, cysteine-rich transcription factor, NF-X1, which binds to the conserved X-box motif of class II MHC genes, were obtained, and the primary amino acid sequence deduced. The major open reading frame encodes a polypeptide of 1,104 amino acids with a symmetrical organization. A central cysteine-rich portion encodes the DNA-binding domain, and is subdivided into seven repeated motifs. This motif is similar to but distinct from the LIM domain and the RING finger family, and is reminiscent of known metal-binding regions. The unique arrangement of cysteines indicates that the consensus sequence CX3CXL-XCGX1-5HXCX3CHXGXC represents a novel cysteine-rich motif. Two lines of evidence indicate that the polypeptide encodes a potent and biologically relevant repressor of HLA-DRA transcription: (a) overexpression of NF-X1 from a retroviral construct strongly decreases transcription from the HLA-DRA promoter; and (b) the NF-X1 transcript is markedly induced late after induction with interferon gamma (IFN-gamma), coinciding with postinduction attenuation of HLA-DRA transcription. The NF-X1 protein may therefore play an important role in regulating the duration of an inflammatory response by limiting the period in which class II MHC molecules are induced by IFN-gamma.
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Affiliation(s)
- Z Song
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
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7
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Whiteside ST, King P, Goodbourn S. A truncated form of the IRF-2 transcription factor has the properties of a postinduction repressor of interferon-beta gene expression. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(18)47125-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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8
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Garoufalis E, Kwan I, Lin R, Mustafa A, Pepin N, Roulston A, Lacoste J, Hiscott J. Viral induction of the human beta interferon promoter: modulation of transcription by NF-kappa B/rel proteins and interferon regulatory factors. J Virol 1994; 68:4707-15. [PMID: 8035474 PMCID: PMC236410 DOI: 10.1128/jvi.68.8.4707-4715.1994] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Multiple regulatory domains within the -100 region of the beta interferon (IFN-beta) promoter control the inducible response of the IFN gene to virus infection. In this study, we demonstrate that the formation of NF-kappa B-specific complexes on the positive regulatory domain II (PRDII) precedes the onset of detectable IFN-beta transcription in Sendai virus-infected cells. By using NF-kappa B subunit-specific antibodies, a temporal shift in the composition of NF-kappa B subunits in association with the PRDII domain is detected as a function of time after virus infection. Furthermore, a virus-induced degradation of I kappa B alpha (MAD3) protein is observed between 2 and 8 h after infection; at later times, de novo synthesis of I kappa B alpha restores I kappa B alpha to levels found in uninduced cells and correlates with the down regulation of IFN-beta transcription. In cotransfection experiments using various NF-kappa B subunit expression plasmids and two copies of PRDII/NF-kappa B linked to a chloramphenicol acetyltransferase reporter gene, we demonstrate that expression of p65, c-Rel, or p50 or combinations of p50-p65 and p65-c-Rel differentially stimulated PRDII-dependent transcription. Coexpression of I kappa B alpha completely abrogated p65-, c-Rel-, or p65-p50-induced gene activity. When the entire IFN-beta promoter (-281 to +19) was used in coexpression studies, synergistic stimulation of IFN-beta promoter activity was obtained when NF-kappa B subunits were coexpressed together with the IFN regulatory factor 1 (IRF-1) transcription factor. Overexpression of either I kappa B or the IRF-2 repressor was able to abrogate inducibility of the IFN-beta promoter. Thus, multiple regulatory events--including differential activation of DNA-binding NF-kappa B heterodimers, degradation of I kappa B alpha, synergistic interaction between IRF-1 and NF-kappa B, and decreased repression by I kappa B and IRF-2--are all required for the transcriptional activation of the IFN-beta promoter.
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Affiliation(s)
- E Garoufalis
- Terry Fox Molecular Oncology Group, Lady Davis Institute for Medical Research, Sir Mortimer B. Davis Jewish General Hospital, Montreal, Quebec, Canada
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9
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Lin R, Mustafa A, Nguyen H, Gewert D, Hiscott J. Mutational analysis of interferon (IFN) regulatory factors 1 and 2. Effects on the induction of IFN-beta gene expression. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)32475-4] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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10
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McKendry R, Pellegrini S, Kerr IM, Stark GR. Constitutive production of alpha and beta interferons in mutant human cell lines. J Virol 1994; 68:4057-62. [PMID: 8189543 PMCID: PMC236917 DOI: 10.1128/jvi.68.6.4057-4062.1994] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Alpha and beta interferons control expression of a selectable marker in the human hypoxanthine phosphoribosyltransferase-negative cell line 2fTGH, in which transcription of gpt is regulated by the upstream region of an interferon-responsive human gene. Selection of mutagenized 2fTGH cells in hypoxanthine-aminopterin-thymidine medium yielded mutants in one recessive (C1) and two dominant (C2 and C3) complementation groups. The mutants constitutively expressed low levels of beta interferon (C1), alpha interferon (C2), or both (C3).
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Affiliation(s)
- R McKendry
- Imperial Cancer Research Fund, London, United Kingdom
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11
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Affiliation(s)
- A R Clark
- Department of Medicine, University of Birmingham, Queen Elizabeth Hospital, U.K
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12
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Ruffner H, Reis LF, Näf D, Weissmann C. Induction of type I interferon genes and interferon-inducible genes in embryonal stem cells devoid of interferon regulatory factor 1. Proc Natl Acad Sci U S A 1993; 90:11503-7. [PMID: 8265581 PMCID: PMC48012 DOI: 10.1073/pnas.90.24.11503] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Overexpression of interferon regulatory factor 1 (IRF-1) can induce expression of the interferon (IFN) beta gene, at least in certain cells. A role of IRF-1 in the activation of IFN-alpha genes has also been claimed. We have generated embryonal stem cells in which both IRF-1 alleles were disrupted. In undifferentiated embryonal stem cells, virus-induced levels of IFN-alpha RNA were similar for wild-type and IRF-1%, and there was little induction of IFN-beta RNA in either cell type. In 8-day differentiated cells, the levels of virus-induced IFN-beta RNA, but not of IFN-alpha RNA, were about 10-fold higher than in undifferentiated cells and only slightly higher in wild-type than in IRF-1% cells. Thus, although IRF-1 at high levels may elicit or augment induction of IFN genes under certain circumstances, it is not essential for IFN gene induction by virus. Lack of IRF-1 had no effect on the IFN-induced expression levels of the IFN-inducible genes tested; however, there was little or no constitutive expression of (2'-5')oligoadenylate synthetase in IRF-1% embryonal stem cells, in contrast to wild-type cells.
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Affiliation(s)
- H Ruffner
- Institut für Molekularbiologie I, University of Zürich, Switzerland
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13
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Au W, Su Y, Raj N, Pitha P. Virus-mediated induction of interferon A gene requires cooperation between multiple binding factors in the interferon alpha promoter region. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(20)80488-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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14
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Charlier M, L'Haridon R, Boisnard M, Martal J, Gaye P. Cloning and structural analysis of four genes encoding interferon-omega in rabbit. JOURNAL OF INTERFERON RESEARCH 1993; 13:313-22. [PMID: 8301151 DOI: 10.1089/jir.1993.13.313] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
By using an ovine interferon-tau (IFN-tau) cDNA probe, four recombinant phages were isolated from a rabbit genomic library and sequenced from nucleotides -450 to 1,300 relative to the CAP site. Each of the four rabbit genes contains an open reading frame of 595 nucleotides and code for proteins that exhibit structural characteristics of the interferon-omega (IFN-omega) family. They display more than 98% identity in their coding regions. The deduced amino acid sequences share > 96% sequence similarity. In contrast, the 5' and 3' noncoding regions have diverged considerably (approximately 50% identity). Amino acid comparisons of rabbit IFN-omega with IFN-omega of other species reveal the highest degree of identity with human (72%), followed by porcine (68%) IFN-omega. Rabbit IFN-omega displays only 57% sequence similarity with ovine IFN-tau. The coding regions of the four genes subcloned in a cytomegalovirus eukaryotic expression vector and transfected in monkey COS-7 cells direct the production of proteins that protect bovine and rabbit cells against vesicular stomatitis virus infection, thus demonstrating that these genes encode fully active IFN proteins. The expression of these genes was studied in Sendai-induced rabbit leukocytes. A single band of poly(A)+RNA hybridized with a rabbit IFN-omega probe under stringent conditions, whereas no IFN-omega transcript was detected with RNA isolated from uninduced leukocytes. Southern blot analysis suggest the existence of at least eight IFN-omega genes or pseudogenes in the rabbit genome.
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Affiliation(s)
- M Charlier
- Unité d'Endocrinologie de l'Embryon, I.N.R.A., Jouy-en-Josas, France
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15
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Bazhan SI, Likhoshvai VA, Belova OE. Theoretical analysis of the possible mechanisms of interferon induction for priming and blocking. Bull Exp Biol Med 1993. [DOI: 10.1007/bf00820234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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16
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The genomic structure of the murine ICSBP gene reveals the presence of the gamma interferon-responsive element, to which an ISGF3 alpha subunit (or similar) molecule binds. Mol Cell Biol 1993. [PMID: 8321202 DOI: 10.1128/mcb.13.7.3951] [Citation(s) in RCA: 104] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
ICSBP, a member of the interferon regulatory factor family, is expressed predominantly in lymphoid tissues and is induced by gamma interferon (IFN-gamma). We have studied the genomic organization of the murine ICSBP gene and its 5' upstream region. The murine ICSBP gene (Icsbp) is present as a single copy on chromosome 8 and consists of nine exons. Transcription initiates at two juxtaposed sites downstream from the TATA and CAAT boxes and produces two species of ICSBP mRNA (3.0 and 1.7 kb), presumably by differential usage of poly(A)+ signals. A sequence from -175 to -155 was identified to be an IFN response region that conferred IFN-gamma induction upon a heterologous promoter in lymphoid cell line EL4. This region includes a motif, TTCNNGGAA, designated the palindromic IFN response element (pIRE), to which an IFN-gamma-inducible, cycloheximide-sensitive factor(s) binds. A similar palindromic motif was found in the upstream region of the murine IRF-1 gene, the IFN-gamma activation site of the guanylate-binding protein gene and the IFN-gamma-responsive region of the Fc receptor type I gene, all of which competed with the pIRE for factor binding in gel mobility shift assays. We show that the pIRE binding factor reacts with the antibody against the 91-kDa subunit of ISGF3 alpha recently shown to bind to the IFN-gamma activation site. These results suggest that this factor is related to the IFN-gamma activation factor and contains the 91-kDa subunit of ISGF3 alpha. Taken together, pIRE represents an IRE that is distinct from the classical IFN-stimulated response element and that is capable of conferring IFN-gamma induction through the binding of the 91-kDa ISGF3 alpha subunit (or an antigenically similar molecule).
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17
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Kanno Y, Kozak CA, Schindler C, Driggers PH, Ennist DL, Gleason SL, Darnell JE, Ozato K. The genomic structure of the murine ICSBP gene reveals the presence of the gamma interferon-responsive element, to which an ISGF3 alpha subunit (or similar) molecule binds. Mol Cell Biol 1993; 13:3951-63. [PMID: 8321202 PMCID: PMC359937 DOI: 10.1128/mcb.13.7.3951-3963.1993] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
ICSBP, a member of the interferon regulatory factor family, is expressed predominantly in lymphoid tissues and is induced by gamma interferon (IFN-gamma). We have studied the genomic organization of the murine ICSBP gene and its 5' upstream region. The murine ICSBP gene (Icsbp) is present as a single copy on chromosome 8 and consists of nine exons. Transcription initiates at two juxtaposed sites downstream from the TATA and CAAT boxes and produces two species of ICSBP mRNA (3.0 and 1.7 kb), presumably by differential usage of poly(A)+ signals. A sequence from -175 to -155 was identified to be an IFN response region that conferred IFN-gamma induction upon a heterologous promoter in lymphoid cell line EL4. This region includes a motif, TTCNNGGAA, designated the palindromic IFN response element (pIRE), to which an IFN-gamma-inducible, cycloheximide-sensitive factor(s) binds. A similar palindromic motif was found in the upstream region of the murine IRF-1 gene, the IFN-gamma activation site of the guanylate-binding protein gene and the IFN-gamma-responsive region of the Fc receptor type I gene, all of which competed with the pIRE for factor binding in gel mobility shift assays. We show that the pIRE binding factor reacts with the antibody against the 91-kDa subunit of ISGF3 alpha recently shown to bind to the IFN-gamma activation site. These results suggest that this factor is related to the IFN-gamma activation factor and contains the 91-kDa subunit of ISGF3 alpha. Taken together, pIRE represents an IRE that is distinct from the classical IFN-stimulated response element and that is capable of conferring IFN-gamma induction through the binding of the 91-kDa ISGF3 alpha subunit (or an antigenically similar molecule).
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Affiliation(s)
- Y Kanno
- Laboratory of Molecular Growth Regulation, National Institute of Child Health and Human Development, Bethesda, Maryland 20892
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18
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Action of spontaneously produced beta interferon in differentiation of embryonal carcinoma cells through an autoinduction mechanism. Mol Cell Biol 1993. [PMID: 8474445 DOI: 10.1128/mcb.13.5.2846] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In the current study, we have addressed the role of interferons (IFNs) in controlling the differentiation of pluripotent P19 embryonal carcinoma (EC) cells. Blocking IFN activity in the culture medium of differentiating cells with antibodies leads to a strong decrease in the degree of differentiation. The antibodies are active for a relatively short time. During this time, IFN-beta mRNA can be detected in the differentiating cells, as can increases of IFN stimulation response element-binding activity and NF-KB. The timing of IFN action also coincides with the accumulation of cytoplasmic double-stranded RNA (dsRNA) and with a drop in dsRNA unwindase-modificase activity. A model for the involvement of autoinduction of IFN by intracellular dsRNA in the control of differentiation in this system is presented.
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19
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Belhumeur P, Lanoix J, Blais Y, Forget D, Steyaert A, Skup D. Action of spontaneously produced beta interferon in differentiation of embryonal carcinoma cells through an autoinduction mechanism. Mol Cell Biol 1993; 13:2846-57. [PMID: 8474445 PMCID: PMC359673 DOI: 10.1128/mcb.13.5.2846-2857.1993] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
In the current study, we have addressed the role of interferons (IFNs) in controlling the differentiation of pluripotent P19 embryonal carcinoma (EC) cells. Blocking IFN activity in the culture medium of differentiating cells with antibodies leads to a strong decrease in the degree of differentiation. The antibodies are active for a relatively short time. During this time, IFN-beta mRNA can be detected in the differentiating cells, as can increases of IFN stimulation response element-binding activity and NF-KB. The timing of IFN action also coincides with the accumulation of cytoplasmic double-stranded RNA (dsRNA) and with a drop in dsRNA unwindase-modificase activity. A model for the involvement of autoinduction of IFN by intracellular dsRNA in the control of differentiation in this system is presented.
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Affiliation(s)
- P Belhumeur
- Institut du Cancer de Montréal, Québec, Canada
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20
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Interferon consensus sequence-binding protein, a member of the interferon regulatory factor family, suppresses interferon-induced gene transcription. Mol Cell Biol 1993. [PMID: 7678054 DOI: 10.1128/mcb.13.1.588] [Citation(s) in RCA: 109] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We previously isolated a cDNA clone encoding interferon consensus sequence-binding protein (ICSBP), a member of the interferon regulatory factor (IRF) family, that binds to the interferon (IFN)-stimulated response element (ISRE) of many IFN-regulated genes. In this investigation, we studied the functional role of ICSBP by transient cotransfection of ICSBP cDNA with IFN-responsive reporter genes into the human embryonal carcinoma cell line N-Tera2. These cells were shown not to express ICSBP or IRF-2, thus allowing functional analysis of transfected cDNAs. Cotransfection of ICSBP into cells treated with retinoic acid or any of the IFNs (alpha, beta, or gamma) repressed expression of a chloramphenicol acetyltransferase reporter driven by the major histocompatibility complex class I gene promoter. Similarly, ICSBP repressed expression of chloramphenicol acetyltransferase reporters driven by the ISREs of the 2'-5' oligoadenylate synthetase, guanylate-binding protein, and ISG-15 genes in IFN-treated cells. The repression was dependent on the presence of the ISRE in the reporter. Deletion analysis showed that the putative N-terminal DNA binding domain of ICSBP by itself is capable of mediating the repression. Using the same cotransfection conditions as for ICSBP, a similar repression of these reporters was observed with IRF-2. Finally, ICSBP repressed the IRF-1-mediated induction of major histocompatibility complex class I and IFN-beta reporters in the absence of IFN or retinoic acid. Taken together, these results suggest that ICSBP is a negative regulatory factor capable of repressing transcription of target genes induced by IFN, retinoic acid, or IRF-1.
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21
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Nelson N, Marks MS, Driggers PH, Ozato K. Interferon consensus sequence-binding protein, a member of the interferon regulatory factor family, suppresses interferon-induced gene transcription. Mol Cell Biol 1993; 13:588-99. [PMID: 7678054 PMCID: PMC358938 DOI: 10.1128/mcb.13.1.588-599.1993] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
We previously isolated a cDNA clone encoding interferon consensus sequence-binding protein (ICSBP), a member of the interferon regulatory factor (IRF) family, that binds to the interferon (IFN)-stimulated response element (ISRE) of many IFN-regulated genes. In this investigation, we studied the functional role of ICSBP by transient cotransfection of ICSBP cDNA with IFN-responsive reporter genes into the human embryonal carcinoma cell line N-Tera2. These cells were shown not to express ICSBP or IRF-2, thus allowing functional analysis of transfected cDNAs. Cotransfection of ICSBP into cells treated with retinoic acid or any of the IFNs (alpha, beta, or gamma) repressed expression of a chloramphenicol acetyltransferase reporter driven by the major histocompatibility complex class I gene promoter. Similarly, ICSBP repressed expression of chloramphenicol acetyltransferase reporters driven by the ISREs of the 2'-5' oligoadenylate synthetase, guanylate-binding protein, and ISG-15 genes in IFN-treated cells. The repression was dependent on the presence of the ISRE in the reporter. Deletion analysis showed that the putative N-terminal DNA binding domain of ICSBP by itself is capable of mediating the repression. Using the same cotransfection conditions as for ICSBP, a similar repression of these reporters was observed with IRF-2. Finally, ICSBP repressed the IRF-1-mediated induction of major histocompatibility complex class I and IFN-beta reporters in the absence of IFN or retinoic acid. Taken together, these results suggest that ICSBP is a negative regulatory factor capable of repressing transcription of target genes induced by IFN, retinoic acid, or IRF-1.
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Affiliation(s)
- N Nelson
- Laboratory of Molecular Growth Regulation, National Institute of Child Health and Human Development, Bethesda, Maryland 20892
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22
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Weisz A, Marx P, Sharf R, Appella E, Driggers P, Ozato K, Levi B. Human interferon consensus sequence binding protein is a negative regulator of enhancer elements common to interferon-inducible genes. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(19)74081-2] [Citation(s) in RCA: 106] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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23
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Dron M, Rebouillat D, Tovey MG. Tandem repeat polymers of a critical region of the human interferon-beta promoter exhibit a marked constitutive activity and enhanced responsiveness to transcriptional regulators in transfected HeLa cells. JOURNAL OF INTERFERON RESEARCH 1992; 12:377-87. [PMID: 1431317 DOI: 10.1089/jir.1992.12.377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Multiple copy tandem repeats polymers of an authentic 30-bp region of the human interferon-beta (IFN-beta) promoter between positions-91 to -62 relative to the cap site or the hexanucleotide GAAAGT derived from this region, both acted as strong constitutive regulatory elements in transfected HeLa cells. Such polymers were unresponsive to treatment with IFN-alpha despite their considerable homology with the IFN-responsive elements of other genes but were highly responsive to treatment of HeLa cells with IFN-gamma. Virus induction of HeLa cells transfected with polymers of the 30-bp region linked to a CAT gene increased the activity of the reporter gene 500- to 2,000-fold over baseline levels. Treatment with IFN-alpha prior to virus induction did not increase further CAT activity. Cotransfection of HeLa cells with the CAT gene under the control of a 12-element tandem repeat polymer of the human IFN-beta promoter and an expression vector for the IRF-1 transcriptional activator markedly increased CAT activity while cotransfection of HeLa cells with the IFN-beta construct together with an expression vector for the transcriptional regulator IRF-2 markedly decreased CAT activity relative to cells transfected with the IFN-beta polymer alone.
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Affiliation(s)
- M Dron
- Laboratory of Viral Oncology, Centre National de la Recherche Scientifique, Villejuif, France
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24
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Abstract
PRDI-BFc and PRDI-BFi are proteins that bind specifically to a regulatory element required for virus induction of the human beta interferon (IFN-beta). PRDI-BFc is a constitutive binding activity, while the PRDI-BFi binding activity is observed only after cells are treated with inducers such as virus or poly(I).poly(C) plus cycloheximide or in some cells by cycloheximide alone. In this paper we report that PRDI-BFc is interferon regulatory factor-2 (IRF-2), a known transcriptional repressor. In addition, we find that PRDI-BFi is a truncated form of IRF-2, lacking approximately 185 C-terminal amino acids. Thus, PRDI-BFi appears to be generated by inducible proteolysis. Although the affinity of PRDI-BFc/IRF-2 for the IFN-beta promoter does not appear to be affected by the removal of C-terminal amino acids, the ability of PRDI-BFi to function as a repressor in cotransfection experiments is significantly less than that of intact IRF-2. Studies have shown that IRF-2 can block the activity of the transcriptional activator IRF-1, which also binds specifically to the IFN-beta gene promoter. Thus, the inducible proteolysis of IRF-2 may be involved in the regulation of the IFN-beta gene or of other genes in which the ratio of IRF-1 to IRF-2 can affect the level of transcription.
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25
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Francis MK, Lehman JM. Altered DNA/protein complexes specific for the beta-interferon regulatory region observed in murine embryonal carcinoma F9 cells. J Cell Biochem 1992; 49:366-77. [PMID: 1429865 DOI: 10.1002/jcb.240490407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Murine embryonal carcinoma (EC) F9 cells do not produce interferon (IFN) at the protein or RNA level in response to inducing agents, while retinoic acid differentiated F9 cells do produce IFN. A probe was constructed spanning positions -104 to -39 of the human beta-IFN upstream regulatory region to examine this developmental control at the level of a transcriptional regulatory mechanism. Gel mobility shift analyses were used to examine this molecular mechanism to determine whether the differential expression of positive or negative trans-acting factors may act to control beta-IFN expression in undifferentiated EC cells. These analyses showed that while nuclear extracts from poly-I,C induced L929 cells, in the IFN producing cell line, showed two shifted bands, nuclear extracts from both induced and uninduced F9 cells showed only one shifted band using the -104/-39 probe. While this single shifted band co-migrated with the faster migrating species of L929 cell extracts, competition analysis revealed differences between the two complexes. An oligonucleotide representing the positive regulatory domain PRDII competed efficiently for the probe when induced F9 cell extracts were examined, but failed to compete when induced L929 cell extracts were examined. In contrast, an oligonucleotide representing the positive regulatory domain PRDI competed very well when induced L929 cell extracts were examined but had only a minimal effect when induced F9 cell extracts were examined. These data suggest the involvement of developmentally regulated transcriptional factor(s) which have yet to be characterized.
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Affiliation(s)
- M K Francis
- Department of Microbiology, Immunology, and Molecular Genetics, Albany Medical College, New York 12208
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26
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Abstract
PRDI-BFc and PRDI-BFi are proteins that bind specifically to a regulatory element required for virus induction of the human beta interferon (IFN-beta). PRDI-BFc is a constitutive binding activity, while the PRDI-BFi binding activity is observed only after cells are treated with inducers such as virus or poly(I).poly(C) plus cycloheximide or in some cells by cycloheximide alone. In this paper we report that PRDI-BFc is interferon regulatory factor-2 (IRF-2), a known transcriptional repressor. In addition, we find that PRDI-BFi is a truncated form of IRF-2, lacking approximately 185 C-terminal amino acids. Thus, PRDI-BFi appears to be generated by inducible proteolysis. Although the affinity of PRDI-BFc/IRF-2 for the IFN-beta promoter does not appear to be affected by the removal of C-terminal amino acids, the ability of PRDI-BFi to function as a repressor in cotransfection experiments is significantly less than that of intact IRF-2. Studies have shown that IRF-2 can block the activity of the transcriptional activator IRF-1, which also binds specifically to the IFN-beta gene promoter. Thus, the inducible proteolysis of IRF-2 may be involved in the regulation of the IFN-beta gene or of other genes in which the ratio of IRF-1 to IRF-2 can affect the level of transcription.
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Affiliation(s)
- V J Palombella
- Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, Massachusetts 02138
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27
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Purification of BBF, a DNA-binding protein recognizing a positive cis-acting element in the mouse alpha 1(III) collagen promoter. J Biol Chem 1992. [DOI: 10.1016/s0021-9258(19)49725-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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28
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Daigneault L, Haggarty A, Meng QH, Skup D. Two distinct pathways of interferon induction as revealed by 2-aminopurine. Nucleic Acids Res 1992; 20:2749-54. [PMID: 1614862 PMCID: PMC336917 DOI: 10.1093/nar/20.11.2749] [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: 12/27/2022] Open
Abstract
Activation and repression of IFN gene expression are controlled primarily at the transcriptional level. In order to elucidate some aspects of the induction mechanism of the IFN genes, we examined the effects of different treatments on IFN production in L929 cells, a well-characterized system, and in primary spleen cells. Our results indicate that 2-Aminopurine (2-AP) inhibits type I IFN (IFN-alpha and IFN-beta) induction in L929 cells but not in spleen cells. In L929 cells, 2-AP inhibited the induction of the MuIFN-beta promoter and of promoters containing tetrahexamer and PRDII sequences linked to a reporter gene. Inhibition of activation of the inducible factors binding to the MuIFN-beta promoter and sub-elements was also observed. In contrast, factors binding to the MuIFN-beta promoter are present constitutively in spleen cell nuclei and their activity is not inhibited by 2-AP. These results suggest that 2-AP inhibits IFN-beta gene induction in L929 cells through blocking of activation of the inducible DNA-binding factors which interact with the IFN-beta promoter.
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29
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Au WC, Raj NB, Pine R, Pitha PM. Distinct activation of murine interferon-alpha promoter region by IRF-1/ISFG-2 and virus infection. Nucleic Acids Res 1992; 20:2877-84. [PMID: 1614874 PMCID: PMC336936 DOI: 10.1093/nar/20.11.2877] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Virus infection in mouse L929 cells activates expression of interferon-alpha 4 (IFN-alpha 4), but not IFN-alpha 6. The integrity of a symmetrical sequence, GTAAAGAAAGT (alpha F1 site); (-103 to -93), present in the 35 nucleotide (nt) long inducible element (IE) (-109 to -75) of the alpha 4 promoter region is essential for the virus-induced expression. In the present study, we have shown that the interferon regulatory factor 1 (IRF-1) can induce expression of both IFN-alpha 4 and -alpha 6 in a transient expression assay. Virus infection cooperates with IRF-1 and further enhances transcription from the alpha 4 promoter, but inhibits the IRF-1-mediated expression from the alpha 6 promoter. The virus-mediated induction is determined by both IRF-1 and alpha F1 sites, while activation by IRF-1 in a cotransfection assay is not greatly influenced by the alpha F1 sequence. The activation of IFN-alpha gene promoters by IRF-1 was limited to the transient expression assay. The integrated alpha 4 promoter or the endogenous IFN-alpha genes could not be induced by transfection with IRF-1 expressing plasmid and IRF-1 did not up-regulate expression of the endogenous IRF-1 gene. However, expression of IRF-1 alone was sufficient to up-regulate the expression of two IFN stimulated genes, 2',5' oligoadenylate synthetase (OAS) and interferon stimulated (ISG)-15 gene. These results suggest that induction of IFN-alpha gene expression by virus infection requires cooperation between IRF-1 and another factor(s) that binds to the alpha F1 sequence.
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Affiliation(s)
- W C Au
- Oncology Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
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30
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Whiteside ST, Visvanathan KV, Goodbourn S. Identification of novel factors that bind to the PRD I region of the human beta-interferon promoter. Nucleic Acids Res 1992; 20:1531-8. [PMID: 1579446 PMCID: PMC312234 DOI: 10.1093/nar/20.7.1531] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Treatment of cells with virus or synthetic double-stranded RNA (dsRNA) leads to the transient transcriptional activation of the beta-interferon gene. Genetic analysis has revealed that the 5' regulatory sequence responsible for this induction contains multiple positive and negative elements. One of these, Positive Regulatory Domain I (PRD I), has been shown to bind the positively-acting transcription factor IRF-1. In this study we show that this element is inducible under conditions where IRF-1 cannot be detected, suggesting that additional cellular factors are involved in the induction process. To investigate the existence of such factors we have analysed the range and properties of PRD I-binding activities present in HeLa cells. In addition to the repressor protein IRF-2, several novel factors can bind to PRD I in uninduced cells: two of these have properties consistent with a role in negative regulation; levels of two others increase upon priming, and may be alternative candidates for activators. Upon induction we also observe a novel factor whose appearance does not depend upon de novo protein synthesis, and which appears to be a truncated form of IRF-2. The potential involvement of these factors in regulating the beta-interferon gene is discussed.
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Affiliation(s)
- S T Whiteside
- Gene Expression Laboratory, Imperial Cancer Research Fund, London, UK
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31
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Du W, Maniatis T. An ATF/CREB binding site is required for virus induction of the human interferon beta gene [corrected]. Proc Natl Acad Sci U S A 1992; 89:2150-4. [PMID: 1532252 PMCID: PMC48614 DOI: 10.1073/pnas.89.6.2150] [Citation(s) in RCA: 92] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
We report the characterization of a distinct regulatory element of the human interferon beta (HuIFN-beta) gene promoter, which we designate PRDIV (positive regulatory domain IV). In previous studies, sequences between -104 and -91 base pairs upstream from the start site of transcription were shown to be required for maximal levels of virus induction in mouse L929 cells. We have localized the essential sequence in this region extending from -99 to at least -91, and we show that this sequence is a binding site for a protein of the activating transcription factor/cAMP response element binding protein (ATF/CREB) family of transcription factors. Mutations in PRDIV that decrease the affinity of one member of this family (ATF-2/CRE-BP1) decrease the level of virus induction in vivo. Moreover, multiple copies of PRDIV can confer both virus and cAMP inducibility upon a minimal promoter in L929 cells, while it is constitutively active in HeLa cells. We conclude that PRDIV is a distinct regulatory element of the HuIFN-beta promoter and that the signal transduction pathways involved in virus and cAMP induction may partially overlap.
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Affiliation(s)
- W Du
- Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, MA 02138
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32
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Reis LF, Harada H, Wolchok JD, Taniguchi T, Vilcek J. Critical role of a common transcription factor, IRF-1, in the regulation of IFN-beta and IFN-inducible genes. EMBO J 1992; 11:185-93. [PMID: 1371248 PMCID: PMC556439 DOI: 10.1002/j.1460-2075.1992.tb05041.x] [Citation(s) in RCA: 187] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Interferon regulatory factor 1 (IRF-1) is a protein that binds to cis-elements within the promoter of interferon (IFN)-beta and some IFN-inducible genes. We used a human fibroblast line, GM-637, to generate stable transfectants constitutively expressing IRF-1 mRNA in either the sense or antisense orientation. Upon induction with poly-(I).poly(C) or Newcastle disease virus, cells expressing sense IRF-1 mRNA produced significantly higher levels of IFN-beta mRNA and protein than control cells, whereas cells expressing antisense IRF-1 mRNA produced little or no IFN-beta mRNA and protein. Furthermore, clear differences were seen among the transfectants in the level of expression of two IFN-induced genes (2'-5'-oligoadenylate synthetase and class I HLA). Our data show that IRF-1 is essential for the induced expression of the IFN-beta gene. The results also indicate an important role of IRF-1 in the expression of IFN-inducible genes and suggest a role for IRF-1 in many other cytokine actions.
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Affiliation(s)
- L F Reis
- Department of Microbiology, New York University Medical Center, NY 10016
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33
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Tanaka N, Taniguchi T. Cytokine gene regulation: regulatory cis-elements and DNA binding factors involved in the interferon system. Adv Immunol 1992; 52:263-81. [PMID: 1442307 DOI: 10.1016/s0065-2776(08)60877-9] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- N Tanaka
- Institute for Molecular and Cellular Biology, Osaka University, Japan
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34
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Pugh CW, Tan CC, Jones RW, Ratcliffe PJ. Functional analysis of an oxygen-regulated transcriptional enhancer lying 3' to the mouse erythropoietin gene. Proc Natl Acad Sci U S A 1991; 88:10553-7. [PMID: 1961720 PMCID: PMC52967 DOI: 10.1073/pnas.88.23.10553] [Citation(s) in RCA: 199] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Erythropoietin, the major hormone controlling red-cell production, is regulated in part through oxygen-dependent changes in the rate of transcription of its gene. Using transient transfection in HepG2 cells, we have defined a DNA sequence, located 120 base pairs 3' to the poly(A)-addition site of the mouse erythropoietin gene, that confers oxygen-regulated expression on a variety of heterologous promoters. The sequence has the typical features of a eukaryotic enhancer. Approximately 70 base pairs are necessary for full activity, but reiteration restores activity to shorter inactive sequences. This enhancer operates in HepG2 and Hep3B cells, but not in Chinese hamster ovary cells or mouse erythroleukemia cells, and responds to cobalt but not to cyanide or 2-deoxyglucose, thus reflecting the physiological control of erythropoietin production accurately.
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Affiliation(s)
- C W Pugh
- Institute of Molecular Medicine, John Radcliffe Hospital, Headington, Oxford, United Kingdom
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35
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Keller AD, Maniatis T. Selection of sequences recognized by a DNA binding protein using a preparative southwestern blot. Nucleic Acids Res 1991; 19:4675-80. [PMID: 1891359 PMCID: PMC328708 DOI: 10.1093/nar/19.17.4675] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We have tested the feasibility of using a preparative scale Southwestern blot to select DNA sequences specifically recognized by a DNA binding protein. We constructed a library of random 15-mer oligonucleotides and screened it using a preparative Southwestern blot with the transcriptional repressor, PRDI-BF1. Several sequences specifically recognized by PRDI-BF1 were isolated. All of these sequences are similar to PRDI, a regulatory element previously demonstrated to bind PRDI-BF1.
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Affiliation(s)
- A D Keller
- Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, MA 02138
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36
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Marziali G, Fiorucci G, Coccia EM, Percario Z, Raber J, Battistini A, Rossi GB, Affabris E, Romeo G. Posttranscriptional regulation of beta interferon expression in erythroid Friend cells treated with gamma interferon. J Virol 1991; 65:4130-6. [PMID: 1649320 PMCID: PMC248846 DOI: 10.1128/jvi.65.8.4130-4136.1991] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Treatment of Friend erythroleukemia cells (FLC) with gamma interferon (IFN-gamma) in the presence of anti-IFN-beta antibodies reduces the effectiveness of the antiviral state and the induction of 2'-5'-oligoadenylate synthetase activity, indicating that the antiviral activity of IFN-gamma in FLC is in part mediated by the production of IFN-beta. Accordingly, IFN-gamma induces a less pronounced antiviral state in FLC resistant to IFN-alpha/beta than in wild-type cells. Moreover, while results of run-on assays indicate that both IFN-alpha and -beta genes are constitutively transcribed in these cells, FLC treatment with IFN-gamma induces only IFN-beta mRNA accumulation. These results indicate that posttranscriptional mechanisms are involved in the regulation of IFN-beta and -alpha expression by IFN-gamma. The low amounts of the induced IFN-beta synergize with IFN-gamma in mounting the potent antiviral effect.
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Affiliation(s)
- G Marziali
- Laboratorio di Virologia, Istituto Superiore di Sanità, Rome, Italy
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37
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Identification of a novel virus-responsive sequence in the promoter of murine interferon-alpha genes. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)99171-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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38
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Mémet S, Besançon F, Bourgeade MF, Thang MN. Direct induction of interferon-gamma- and interferon-alpha/beta-inducible genes by double-stranded RNA. JOURNAL OF INTERFERON RESEARCH 1991; 11:131-41. [PMID: 1919073 DOI: 10.1089/jir.1991.11.131] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Using Northern analysis, we here show that the inducibility by double-stranded (ds) RNA of interferon-alpha/beta-inducible genes is not restricted to a few genes but extends to all the genes known to be stimulated by IFN type I in fibroblasts. Moreover, we show that some genes, preferentially regulated by IFN-gamma, are also activated by dsRNA. We present a series of arguments demonstrating that the induction by dsRNA is not mediated by IFN. In addition to the fact that this induction occurs in the presence of cycloheximide and/or anti-IFN-alpha/beta antibodies in fibroblasts, we observed that, in IFN-resistant Daudi cells, ISG15 and IP-10 genes which are not induced by IFN-beta, are still inducible by dsRNA. dsRNA is also still active on 2-5 AS and ISG15 genes in cells carrying homozygous deletions of IFN alpha/beta genes. Actinomycin D experiments and nuclear in vitro elongation assays reveal that the induction by dsRNA involves, as its early step, a transcriptional event. This induction was found not to require protein synthesis, suggesting that activation of preexisting cellular factors is involved. The opposite inducibility by dsRNA of IFN-beta and 2',5'-oligoadenylate (2-5A) synthetase genes in serum-deprived fibroblasts indicates that pathways of induction by dsRNA of these two genes are not identical. Inhibition by 2-aminopurine of the induction of IFN-inducible mRNAs by IFN-beta or dsRNA suggests the participation of a protein kinase in their mechanism of action.
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Affiliation(s)
- S Mémet
- Unité 245 INSERM, Centre INSERM, Hôpital St.-Antoine, Paris, France
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39
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Abstract
The study of double-stranded RNA (dsRNA) encompasses a variety of fields. Basic research in this area has contributed to a greater mechanistic understanding of gene induction, tumor cell growth arrest, the establishment of antiviral states, and immunomodulation. Because of the possible clinical value of these molecules, physicians are now exploring the use of synthetic dsRNA to treat patients with cancer, HIV-1 disease, and immune dysfunction. Continued studies of the mechanisms of action of dsRNA are likely to suggest an even wider scope of clinical applications.
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Affiliation(s)
- D S Haines
- Department of Neoplastic Diseases, Hahnemann University, Philadelphia, Pennsylvania 19102
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40
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Keller AD, Maniatis T. Identification and characterization of a novel repressor of beta-interferon gene expression. Genes Dev 1991; 5:868-79. [PMID: 1851123 DOI: 10.1101/gad.5.5.868] [Citation(s) in RCA: 283] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We have identified and characterized a novel repressor of human beta-interferon (beta-IFN) gene expression. This protein, designated PRDI-BF1, binds specifically to the PRDI element of the beta-IFN gene promoter and is distinct from previously reported proteins that bind to this sequence. PRDI-BF1 is an 88-kD protein containing five zinc-finger motifs. Cotransfection experiments in cultured mammalian cells revealed that PRDI-BF1 is a potent repressor of PRDI-dependent transcription. PRDI-BF1 blocks virus induction of the intact beta-IFN gene promoter and of synthetic promoters containing multiple PRDI sites. PRDI-BF1 can also block the SV40 enhancer when PRDI sites are located between the enhancer and the promoter. This repression is highly dependent on the location of the PRDI sites, however, indicating that PRDI-BF1 cannot act at a distance. On the basis of the properties of PRDI-BF1 and the observation that PRDI-BF1 mRNA accumulation is virus inducible, we propose that PRDI-BF1 may act as a postinduction repressor of the beta-IFN gene by displacing positive regulatory proteins from the PRDI site of the promoter.
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Affiliation(s)
- A D Keller
- Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, Massachusetts 02138
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41
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Coccia EM, Vaiman D, Raber J, Marziali G, Fiorucci G, Orsatti R, Cohen B, Nissim N, Romeo G, Affabris E. Protein binding to the interferon response enhancer correlates with interferon induction of 2'-5'-oligoadenylate synthetase in normal and interferon-resistant Friend cells. J Virol 1991; 65:2081-7. [PMID: 1705997 PMCID: PMC240065 DOI: 10.1128/jvi.65.4.2081-2087.1991] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The induction of transcription of the 2'-5'-oligoadenylate (2-5A) synthetase gene by type I (alpha/beta) and type II (gamma) interferons (IFNs) has been studied in wild-type (w.t.) and IFN-resistant Friend leukemia cells (FLC). Following IFN treatment, new complexes are formed in vitro between the IFN-responsive sequence (IRS) of the 2-5A synthetase gene and cellular proteins. Within minutes after IFN-alpha/beta addition to w.t. FLC, an IRS-protein complex, designated F1, is detected, as already observed in several human cell lines. In response to IFN-gamma, a novel complex, designated Fg, is observed in w.t. FLC. The Fg complex appears within 3 h, while an F1-like complex is faintly visible 10 to 24 h later. In the IFN-alpha/beta-resistant FLC, IFN-gamma induces only the Fg complex and fails to induce F1. Fg formation is correlated with the IFN-gamma-induced transcription of the 2-5A synthetase gene and the appearance of the corresponding enzymatic activity in both w.t. and IFN-alpha/beta-resistant FLC. These findings suggest that F1 and Fg represent two distinct effector complexes by which type I and type II IFNs, respectively, induce 2-5A synthetase.
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Affiliation(s)
- E M Coccia
- Laboratorio di Virologia, Istituto Superiore di Sanità, Rome, Italy
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42
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Näf D, Hardin SE, Weissmann C. Multimerization of AAGTGA and GAAAGT generates sequences that mediate virus inducibility by mimicking an interferon promoter element. Proc Natl Acad Sci U S A 1991; 88:1369-73. [PMID: 1705037 PMCID: PMC51019 DOI: 10.1073/pnas.88.4.1369] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Multimeric AAGTGA and GAAAGT, when inserted before a minimal promoter, mediate virus-inducible transcription. We have determined that the active sequence within these multimers is TGAAAGTGAAAGT, which is structurally similar to GAGAAGTGAAAGT, a positive response element delineated in the beta-interferon gene promoter. Both sequences behave like protoenhancers and are similar as regards induction by virus or interferon regulatory factor 1 when supported by a simian virus 40 enhancer.
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Affiliation(s)
- D Näf
- Institut für Molekularbiologie I. Universität Zürich, Switzerland
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43
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44
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The genes for the trophoblast interferons and the related interferon-alpha II possess distinct 5‘-promoter and 3‘-flanking sequences. J Biol Chem 1991. [DOI: 10.1016/s0021-9258(18)49954-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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45
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Blanchet O, Bourge JF, Zinszner H, Tatari Z, Degos L, Paul P. DNA binding of regulatory factors interacting with MHC-class-I gene enhancer correlates with MHC-class-I transcriptional level in class-I-defective cell lines. INTERNATIONAL JOURNAL OF CANCER. SUPPLEMENT = JOURNAL INTERNATIONAL DU CANCER. SUPPLEMENT 1991; 6:138-45. [PMID: 1906051 DOI: 10.1002/ijc.2910470725] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Tumor cells frequently show a lack of surface class-I major histocompatibility complex (MHC) antigen expression. These molecules are key recognition structures for immune rejection of tumor cells and their absence at the surface of tumor cells could favor the progression of tumors. We have analyzed the transcriptional mechanisms that could lead to suppression of MHC-class-I expression in human tumor cell K562. The expression of MHC-class-I genes is highly controlled by regulatory factors interacting with an enhancer sequence upstream of MHC-class-I genes. In this report we show that DNA binding activity of 2 regulatory factors, KBFI and NF-kappa B, known to be essential for constitutive expression of MHC-class-I genes, is deficient in nuclear extracts from K562 cells. Induction of class-I gene expression at the surface of tumor cells by interferon-gamma (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha) shows that TNF-alpha can act in synergy with IFN-gamma to induce DNA binding of both factors NF-kappa B and KBFI to the class-I gene enhancer and that this induction of transcriptional factors is correlated with enhancement of MHC-class-I mRNA transcription and cell-surface antigen expression.
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MESH Headings
- Antibodies, Monoclonal
- Base Sequence
- Blotting, Northern
- Cell Line
- Cell Nucleus/drug effects
- Cell Nucleus/physiology
- DNA Probes
- DNA-Binding Proteins/metabolism
- Enhancer Elements, Genetic
- Gene Expression/drug effects
- Gene Expression Regulation, Neoplastic
- Genes, MHC Class I
- HeLa Cells/immunology
- Humans
- Interferon-gamma/pharmacology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/immunology
- Molecular Sequence Data
- Oligonucleotide Probes
- Polymerase Chain Reaction/methods
- RNA, Neoplasm/genetics
- RNA, Neoplasm/isolation & purification
- Recombinant Proteins
- Transcription, Genetic/drug effects
- Tumor Necrosis Factor-alpha/pharmacology
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Affiliation(s)
- O Blanchet
- INSERM U93, Centre Hayem, Hôpital Saint-Louis, Paris, France
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46
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Whittemore LA, Maniatis T. Postinduction repression of the beta-interferon gene is mediated through two positive regulatory domains. Proc Natl Acad Sci U S A 1990; 87:7799-803. [PMID: 2172963 PMCID: PMC54837 DOI: 10.1073/pnas.87.20.7799] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Virus induction of the human beta-interferon (beta-IFN) gene results in an increase in the rate of beta-IFN mRNA synthesis, followed by a rapid postinduction decrease. In this paper, we show that two beta-IFN promoter elements, positive regulatory domains I and II (PRDI and PRDII), which are required for virus induction of the beta-IFN gene are also required for the postinduction turnoff. Although protein synthesis is not necessary for activation, it is necessary for repression of these promoter elements. Examination of nuclear extracts from cells infected with virus reveals the presence of virus-inducible, cycloheximide-sensitive, DNA-binding activities that interact specifically with PRDI or PRDII. We propose that the postinduction repression of beta-IFN gene transcription involves virus-inducible repressors that either bind directly to the positive regulatory elements of the beta-IFN promoter or inactivate the positive regulatory factors bound to PRDI and PRDII.
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Affiliation(s)
- L A Whittemore
- Department of Biochemistry and Molecular Biology, Harvard University, Cambridge, MA 02138
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47
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The permissive role of glucocorticoids on interleukin-1 stimulation of angiotensinogen gene transcription is mediated by an interaction between inducible enhancers. Mol Cell Biol 1990. [PMID: 2370871 DOI: 10.1128/mcb.10.8.4389] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The acute-phase activation of the rat angiotensinogen (rAT) gene in liver cells is a transcriptional event mediated through an interleukin-1-inducible, NF kappa B-binding, cis-acting element (the acute-phase response element [APRE]). Using a cell culture model for the acute-phase response, we showed that the increase in angiotensionogen mRNA in H35 rat hepatoma cells requires costimulation with glucocorticoids and cytokines. Stably transfected rAT promoter-luciferase reporter genes were also activated by cytokines only in the presence of glucocorticoids. This permissive role of glucocorticoids is dependent on the expression of functional glucocorticoid receptors, because in HepG2 cells naturally deficient in such receptors, rAT gene-luciferase reporter constructs responded to interleukin-1 only when cotransfected with an expression vector for the glucocorticoid receptor. Point mutations in the two rAT gene glucocorticoid response elements located adjacent to the APRE led to loss of interleukin-1 inducibility. Induction of luciferase activity in transfected cells occurred even in the presence of cycloheximide, demonstrating that this synergistic response did not depend on new protein synthesis. Thus, a direct interaction between the interleukin-1-inducible NF kappa B-binding APRE and glucocorticoid response elements, located in cis, underlies the acute-phase activation of the rAT gene.
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48
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Synergism between distinct enhanson domains in viral induction of the human beta interferon gene. Mol Cell Biol 1990. [PMID: 2370859 DOI: 10.1128/mcb.10.8.3987] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This study demonstrates distinct virus-inducible enhanson properties for three regions of the human beta interferon (IFN-beta) promoter; maximum virus inducibility required syngerism among all three enhansons. Expression of the IRF-1 transcription factor differentially increased the expression of plasmids containing (AAGTGA)4 or PRDIII (-94 to -78) motifs but was inefficient in the induction of the intact IFN-beta promoter. The human T-cell lymphotropic virus type I Tax protein was a strong positive activator of PRDII (-64 to -55)-containing plasmids but was also unable to stimulate the IFN-beta promoter. Induction of the intact IFN-beta promoter linked to a reporter plasmid was achieved in lymphoid and epithelioid cellular backgrounds by a triple transfection with IRF-1 and Tax expression plasmids or a combination of IRF-1 and phorbol ester, indicating that at least two trans-activating events and the association of two proteins on the promoter template are required for IFN-beta activation.
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49
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Leblanc JF, Cohen L, Rodrigues M, Hiscott J. Synergism between distinct enhanson domains in viral induction of the human beta interferon gene. Mol Cell Biol 1990; 10:3987-93. [PMID: 2370859 PMCID: PMC360909 DOI: 10.1128/mcb.10.8.3987-3993.1990] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
This study demonstrates distinct virus-inducible enhanson properties for three regions of the human beta interferon (IFN-beta) promoter; maximum virus inducibility required syngerism among all three enhansons. Expression of the IRF-1 transcription factor differentially increased the expression of plasmids containing (AAGTGA)4 or PRDIII (-94 to -78) motifs but was inefficient in the induction of the intact IFN-beta promoter. The human T-cell lymphotropic virus type I Tax protein was a strong positive activator of PRDII (-64 to -55)-containing plasmids but was also unable to stimulate the IFN-beta promoter. Induction of the intact IFN-beta promoter linked to a reporter plasmid was achieved in lymphoid and epithelioid cellular backgrounds by a triple transfection with IRF-1 and Tax expression plasmids or a combination of IRF-1 and phorbol ester, indicating that at least two trans-activating events and the association of two proteins on the promoter template are required for IFN-beta activation.
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Affiliation(s)
- J F Leblanc
- Lady Davis Institute for Medical Research, Sir Mortimer B. Davis-Jewish General Hospital, Montreal, Quebec, Canada
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50
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Ron D, Brasier AR, Wright KA, Habener JF. The permissive role of glucocorticoids on interleukin-1 stimulation of angiotensinogen gene transcription is mediated by an interaction between inducible enhancers. Mol Cell Biol 1990; 10:4389-95. [PMID: 2370871 PMCID: PMC360996 DOI: 10.1128/mcb.10.8.4389-4395.1990] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The acute-phase activation of the rat angiotensinogen (rAT) gene in liver cells is a transcriptional event mediated through an interleukin-1-inducible, NF kappa B-binding, cis-acting element (the acute-phase response element [APRE]). Using a cell culture model for the acute-phase response, we showed that the increase in angiotensionogen mRNA in H35 rat hepatoma cells requires costimulation with glucocorticoids and cytokines. Stably transfected rAT promoter-luciferase reporter genes were also activated by cytokines only in the presence of glucocorticoids. This permissive role of glucocorticoids is dependent on the expression of functional glucocorticoid receptors, because in HepG2 cells naturally deficient in such receptors, rAT gene-luciferase reporter constructs responded to interleukin-1 only when cotransfected with an expression vector for the glucocorticoid receptor. Point mutations in the two rAT gene glucocorticoid response elements located adjacent to the APRE led to loss of interleukin-1 inducibility. Induction of luciferase activity in transfected cells occurred even in the presence of cycloheximide, demonstrating that this synergistic response did not depend on new protein synthesis. Thus, a direct interaction between the interleukin-1-inducible NF kappa B-binding APRE and glucocorticoid response elements, located in cis, underlies the acute-phase activation of the rAT gene.
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Affiliation(s)
- D Ron
- Laboratory of Molecular Endocrinology, Massachusetts General Hospital, Boston
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