1
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Boija A, Klein IA, Sabari BR, Dall'Agnese A, Coffey EL, Zamudio AV, Li CH, Shrinivas K, Manteiga JC, Hannett NM, Abraham BJ, Afeyan LK, Guo YE, Rimel JK, Fant CB, Schuijers J, Lee TI, Taatjes DJ, Young RA. Transcription Factors Activate Genes through the Phase-Separation Capacity of Their Activation Domains. Cell 2018; 175:1842-1855.e16. [PMID: 30449618 PMCID: PMC6295254 DOI: 10.1016/j.cell.2018.10.042] [Citation(s) in RCA: 984] [Impact Index Per Article: 164.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 08/20/2018] [Accepted: 10/16/2018] [Indexed: 01/19/2023]
Abstract
Gene expression is controlled by transcription factors (TFs) that consist of DNA-binding domains (DBDs) and activation domains (ADs). The DBDs have been well characterized, but little is known about the mechanisms by which ADs effect gene activation. Here, we report that diverse ADs form phase-separated condensates with the Mediator coactivator. For the OCT4 and GCN4 TFs, we show that the ability to form phase-separated droplets with Mediator in vitro and the ability to activate genes in vivo are dependent on the same amino acid residues. For the estrogen receptor (ER), a ligand-dependent activator, we show that estrogen enhances phase separation with Mediator, again linking phase separation with gene activation. These results suggest that diverse TFs can interact with Mediator through the phase-separating capacity of their ADs and that formation of condensates with Mediator is involved in gene activation.
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Affiliation(s)
- Ann Boija
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Isaac A Klein
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Benjamin R Sabari
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | | | - Eliot L Coffey
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Alicia V Zamudio
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Charles H Li
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Krishna Shrinivas
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Institute of Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - John C Manteiga
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Nancy M Hannett
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Brian J Abraham
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Lena K Afeyan
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Yang E Guo
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Jenna K Rimel
- Department of Biochemistry, University of Colorado, Boulder, CO 80303, USA
| | - Charli B Fant
- Department of Biochemistry, University of Colorado, Boulder, CO 80303, USA
| | - Jurian Schuijers
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Tong Ihn Lee
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA
| | - Dylan J Taatjes
- Department of Biochemistry, University of Colorado, Boulder, CO 80303, USA
| | - Richard A Young
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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2
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Inamoto I, Chen G, Shin JA. The DNA target determines the dimerization partner selected by bHLHZ-like hybrid proteins AhRJun and ArntFos. MOLECULAR BIOSYSTEMS 2017; 13:476-488. [DOI: 10.1039/c6mb00795c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The molecular basis of protein–partner selection and DNA binding of the basic helix–loop–helix (bHLH) and basic region-leucine zipper (bZIP) superfamilies of dimeric transcription factors is fundamental toward understanding gene regulation.
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Affiliation(s)
- Ichiro Inamoto
- Department of Chemistry
- University of Toronto
- Mississauga
- Canada L5L 1C6
| | - Gang Chen
- Department of Chemistry
- University of Toronto
- Mississauga
- Canada L5L 1C6
| | - Jumi A. Shin
- Department of Chemistry
- University of Toronto
- Mississauga
- Canada L5L 1C6
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3
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Both homo and heterodimers of Marek's disease virus encoded Meq protein contribute to transformation of lymphocytes in chickens. Virology 2010; 399:312-21. [PMID: 20137800 DOI: 10.1016/j.virol.2010.01.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Revised: 11/27/2009] [Accepted: 01/05/2010] [Indexed: 01/21/2023]
Abstract
Marek' disease virus serotype-1, also know as Gallid herpesvirus 2 (GaHV-2), elicits T-cell lymphomas in chickens. The GaHV-2 genome encodes an oncoprotein, Meq, with similarity to the Jun/Fos family of proteins. We have previously shown that Meq homodimers are not sufficient to induce lymphomas in chickens. In this study, we investigated the role of Meq heterodimers in the pathogenicity of GaHV-2 by generating a chimeric meq gene, which contains the leucine zipper region of Fos (meqFos). A recombinant virus containing the meqFos gene in place of parental meq, rMd5-MeqFos, was not capable of transforming chicken lymphocytes, indicating that heterodimerization of Meq alone is not sufficient for transformation. In addition, the recovery of the oncogenic phenotype by a recombinant virus encoding one copy each of MeqGCN (homodimer) and MeqFos (heterodimer) conclusively demonstrates that both homo and heterodimerization of Meq are required for oncogenesis.
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4
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Qiang M, Ticku MK. Role of AP-1 in ethanol-induced N-methyl-d-aspartate receptor 2B subunit gene up-regulation in mouse cortical neurons. J Neurochem 2005; 95:1332-41. [PMID: 16313514 DOI: 10.1111/j.1471-4159.2005.03464.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Activator protein 1 (AP-1) has been reported to regulate the gene expression in a wide variety of cellular processes in response to stimuli. In this study, we investigated the DNA-protein binding activities and promoter activity in the N-methyl-D-aspartate R2B (NR2B) gene AP-1 site in normal and ethanol-treated cultured neurons. The identity of the AP-1 site as the functional binding factor is suggested by the specific binding of nuclear extract derived from cultured cortical neurons to the labeled probes and the specific antibody-induced supershift. Mutations in the core sequence resulted in a significantly reduced promoter activity and the ability to compete for the binding. Moreover, treatment of the cultured neuron with 75 mm ethanol for 5 days caused a significant increase in the AP-1 binding activity and promoter activity. The AP-1 DNA-binding complex in control and ethanol-treated nuclear extract was composed of c-Fos, FosB, c-Jun, JunD, and phosphorylated CREB (p-CREB). Western blot analysis showed that p-CREB and FosB significantly increased, whereas c-Jun decreased. The DNA affinity precipitation assay indicated that FosB, p-CREB, and c-Jun increased in the AP-1 complex following ethanol treatment. These results suggest that AP-1 is an active regulator of the NR2B transcription and ethanol-induced changes may result at multiple levels in the regulation including AP-1 proteins expression, CREB phosphorylation and perhaps reorganization of dimmers.
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Affiliation(s)
- Mei Qiang
- Department of Pharmacology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229-3900, USA.
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5
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Basbous J, Arpin C, Gaudray G, Piechaczyk M, Devaux C, Mesnard JM. The HBZ factor of human T-cell leukemia virus type I dimerizes with transcription factors JunB and c-Jun and modulates their transcriptional activity. J Biol Chem 2003; 278:43620-7. [PMID: 12937177 DOI: 10.1074/jbc.m307275200] [Citation(s) in RCA: 165] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The human T-cell leukemia virus type I (HTLV-I)-encoded Tax protein activates transcription from the viral promoter via association with the cellular basic leucine zipper factor cAMP-response element-binding protein-2. Tax is also able to induce cellular transformation of T lymphocytes probably by modulating transcriptional activity of cellular factors, including nuclear factor-kappaB, E2F, activator protein-1 (AP-1), and p53. Recently, we characterized in HTLV-I-infected cells the presence of a novel viral protein, HBZ, encoded by the complementary strand of the HTLV-I RNA genome (Gaudray, G., Gachon, F., Basbous, J., Biard-Piechaczyk, M., Devaux, C., and Mesnard, J.-M. (2002) J. Virol. 76, 12813-12822). HBZ is a nuclear basic leucine zipper protein that down-regulates Tax-dependent viral transcription by inhibiting the binding of cAMP-response element-binding protein-2 to the HTLV-I promoter. In searching for other cellular targets of HBZ, we identified two members of the Jun family, JunB and c-Jun. Co-immunoprecipitation and cellular colocalization confirmed that HBZ interacts in vivo with JunB and c-Jun. When transiently introduced into CEM cells with a reporter gene containing the AP-1 site from the collagenase promoter, HBZ suppressed transactivation by c-Jun. On the other hand, the combination of HBZ with Jun-B had higher transcriptional activity than JunB alone. Consistent with the structure of its basic domain, we demonstrate that HBZ decreases the DNA-binding activity of c-Jun and JunB. Last, we show that c-Jun is no longer capable of activating the basal expression of the HTLV-I promoter in the presence of HBZ in vivo. Our results support the hypothesis that HBZ could be a negative modulator of the Tax effect by controlling Tax expression at the transcriptional level and by attenuating activation of AP-1 by Tax.
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Affiliation(s)
- Jihane Basbous
- Laboratoire Infections Rétrovirales et Signalisation Cellulaire, CNRS/Université Montpellier I, Unité Mixte de Recherche 5121/Institut Fédératif de Recherche 122, Institut de Biologie, 4 Boulevard Henri IV, 34960 Montpellier Cedex 2, France
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6
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Abstract
Cellular Jun (c-Jun) and viral Jun (v-Jun) can induce oncogenic transformation. For this activity, c-Jun requires an upstream signal, delivered by the Jun N-terminal kinase (JNK). v-Jun does not interact with JNK; it is autonomous and constitutively active. v-Jun and c-Jun address overlapping but not identical sets of genes. Whether all genes essential for transformation reside within the overlap of the v-Jun and c-Jun target spectra remains to be determined. The search for transformation-relevant targets of Jun is moving into a new stage with the application of DNA microarrays technology. Genetic screens and functional tests remain a necessity for the identification of genes that control the oncogenic phenotype.
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Affiliation(s)
- P K Vogt
- Department of Molecular and Experimental Medicine, The Scripps Reasearch Institute, 10550 North Torrey Pines Drive, La Jolla, California, CA 9203, USA
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7
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Tosteson MT, Kim JB, Goldstein DJ, Tosteson DC. Ion channels formed by transcription factors recognize consensus DNA sequences. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1510:209-18. [PMID: 11342159 DOI: 10.1016/s0005-2736(00)00351-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Transcription factors (TFs) are proteins which bind to specific DNA sequences and thus participate in the regulation of the initiation of transcription. We report in this communication our observations that several of these proteins interact with lipid membranes and form ion-permeable channels. For each of the TFs that we studied, the single channel conductance was distinctively different, i.e. each TF had its own electrical signature. More importantly, we show for the first time that addition of cognate double-stranded DNA sequences leads to a specific response: an increase in the conductance of the TF-containing membrane. Strikingly, the effect of cognate DNA was observed when it was added to the trans-side of the membrane (opposite to where the TF was added), strongly suggesting that the TFs span the membrane and that the DNA-binding domain is trans-accessible. Alterations in the primary structure of the TF factors in their basic and DNA-binding regions change the characteristics of the conductance of the protein-containing membranes as well as the response to DNA addition, reinforcing the notion that the changes we measure are due to specific interactions.
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Affiliation(s)
- M T Tosteson
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
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8
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Rinehart-Kim J, Johnston M, Birrer M, Bos T. Alterations in the gene expression profile of MCF-7 breast tumor cells in response to c-Jun. Int J Cancer 2000; 88:180-90. [PMID: 11004666 DOI: 10.1002/1097-0215(20001015)88:2<180::aid-ijc6>3.0.co;2-h] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
MCF7 breast tumor cells overexpressing human c-Jun exhibit a transformed phenotype characterized not only by increased tumorigenicity but also by enhanced motility and invasion. The cellular phenotypic response to c-Jun overexpression is likely due, at least in part, to altered patterns of gene expression. In order to begin to understand the complexities by which elevated production of c-Jun alters the state of the cell, we have profiled the expression of 588 different genes by comparative hybridization. By using this approach, we have identified a total of 21 upregulated or downregulated gene targets responsive to c-Jun overexpression. Interestingly, 8 of these genes have been previously found associated with c-Jun or AP-1 activity and therefore provide internal validation for this approach to target gene discovery. The remaining 13 genes represent potential new c-Jun regulated target genes. Genomic sequence information was available for 15 of the 21 genes identified in this screen. Analysis of these genomic sequences revealed the presence of AP-1 or AP-1-like sequences in 12 of the 15 genes examined. Consistent with a direct mechanism of target regulation by c-Jun, gel shift analysis of selected AP-1-containing promoter regions revealed elevated and specific binding by proteins present in nuclear extracts of c-Jun expressing MCF7 cells.
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Affiliation(s)
- J Rinehart-Kim
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia, USA
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9
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Haines BP, Voyle RB, Rathjen PD. Intracellular and extracellular leukemia inhibitory factor proteins have different cellular activities that are mediated by distinct protein motifs. Mol Biol Cell 2000; 11:1369-83. [PMID: 10749936 PMCID: PMC14853 DOI: 10.1091/mbc.11.4.1369] [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: 12/29/2022] Open
Abstract
Although many growth factors and cytokines have been shown to be localized within the cell and nucleus, the mechanism by which these molecules elicit a biological response is not well understood. The cytokine leukemia inhibitory factor (LIF) provides a tractable experimental system to investigate this problem, because translation of alternatively spliced transcripts results in the production of differentially localized LIF proteins, one secreted from the cell and acting via cell surface receptors and the other localized within the cell. We have used overexpression analysis to demonstrate that extracellular and intracellular LIF proteins can have distinct cellular activities. Intracellular LIF protein is localized to both nucleus and cytoplasm and when overexpressed induces apoptosis that is inhibited by CrmA but not Bcl-2 expression. Mutational analysis revealed that the intracellular activity was independent of receptor interaction and activation and reliant on a conserved leucine-rich motif that was not required for activation of cell surface receptors by extracellular protein. This provides the first report of alternate intracellular and extracellular cytokine activities that result from differential cellular localization of the protein and are mediated by spatially distinct motifs.
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Affiliation(s)
- B P Haines
- Department of Biochemistry, University of Adelaide, Adelaide, South Australia 5005, Australia
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10
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Bos TJ, Margiotta P, Bush L, Wasilenko W. Enhanced cell motility and invasion of chicken embryo fibroblasts in response to Jun over-expression. Int J Cancer 1999; 81:404-10. [PMID: 10209955 DOI: 10.1002/(sici)1097-0215(19990505)81:3<404::aid-ijc14>3.0.co;2-i] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Malignant tumor cells exhibit a number of distinct properties involved not only with deregulated cell proliferation but also enhanced migration and invasion. The Jun oncogene has been well studied in regard to its role in cell proliferation. Many of the target genes deregulated by Jun encode matrix metalloproteases (MMPs) such as MMP1, MMP3 and MMP9. These targets implicate a prominent role for Jun in tumor cell invasion, in addition to its role in growth transformation. To investigate this possibility, we have examined the effect of over-expression of transforming and non-transforming versions of Jun on motility and invasion of chicken embryo fibroblasts (CEFs). We found that over-expression of either form of Jun results in elevated intrinsic cellular motility as well as increased motility in response to several different chemo-attractants, including 3T3-conditioned media, basic fibroblast growth factor, hepatocyte growth factor and Matrigel. The capacity of these cells to invade through Matrigel is also elevated as a result of Jun over-expression. In addition to these effects, CEFs expressing Jun secrete factors that stimulate the motility of a human tongue carcinoma cell line. Our results suggest that Jun plays an important role in the potentiation of cell motility and invasion through multiple mechanisms.
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Affiliation(s)
- T J Bos
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, USA.
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11
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Herdegen T, Leah JD. Inducible and constitutive transcription factors in the mammalian nervous system: control of gene expression by Jun, Fos and Krox, and CREB/ATF proteins. BRAIN RESEARCH. BRAIN RESEARCH REVIEWS 1998; 28:370-490. [PMID: 9858769 DOI: 10.1016/s0165-0173(98)00018-6] [Citation(s) in RCA: 1054] [Impact Index Per Article: 40.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This article reviews findings up to the end of 1997 about the inducible transcription factors (ITFs) c-Jun, JunB, JunD, c-Fos, FosB, Fra-1, Fra-2, Krox-20 (Egr-2) and Krox-24 (NGFI-A, Egr-1, Zif268); and the constitutive transcription factors (CTFs) CREB, CREM, ATF-2 and SRF as they pertain to gene expression in the mammalian nervous system. In the first part we consider basic facts about the expression and activity of these transcription factors: the organization of the encoding genes and their promoters, the second messenger cascades converging on their regulatory promoter sites, the control of their transcription, the binding to dimeric partners and to specific DNA sequences, their trans-activation potential, and their posttranslational modifications. In the second part we describe the expression and possible roles of these transcription factors in neural tissue: in the quiescent brain, during pre- and postnatal development, following sensory stimulation, nerve transection (axotomy), neurodegeneration and apoptosis, hypoxia-ischemia, generalized and limbic seizures, long-term potentiation and learning, drug dependence and withdrawal, and following stimulation by neurotransmitters, hormones and neurotrophins. We also describe their expression and possible roles in glial cells. Finally, we discuss the relevance of their expression for nervous system functioning under normal and patho-physiological conditions.
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Affiliation(s)
- T Herdegen
- Institute of Pharmacology, University of Kiel, Hospitalstrasse 4, 24105, Kiel,
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12
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Grandien K, Berkenstam A, Gustafsson JA. The estrogen receptor gene: promoter organization and expression. Int J Biochem Cell Biol 1997; 29:1343-69. [PMID: 9570132 DOI: 10.1016/s1357-2725(97)89967-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The estrogen receptor (ER) is a ligand-activated transcription factor and a member of a large family of nuclear hormone receptors. As a mediator of estrogen hormone action, the ER is involved in many important physiological processes. ER gene expression has been demonstrated to be restricted to certain tissues and under complex hormonal control. However, the molecular mechanisms involved have remained largely unknown. Due to this lack of knowledge an investigation was undertaken to characterize the promoter organization of ER gene and investigate its expression. Approximately 3 kb of the 5' flanking region of the human ER (hER) gene was isolated and sequenced. By performing RT-PCR and RACE experiments it was shown that the hER gene is transcribed from three different promoters. Transcription of the hER gene from these promoters yields three different mRNA isoforms with unique 5' untranslated regions (5'UTRs), but identical coding regions. The expression pattern of the hER mRNA isoforms was investigated by RT-PCR. Both the A- and B-mRNA isoforms were found to be expressed in breast and uterus, whereas expression of the C-transcript was predominantly detected in liver. In bone cells only expression of the B-mRNA could be detected. The steady-state levels of the A- and B-transcripts in normal breast and uterus were quantified and compared with the hER mRNA levels in established cancer cell lines derived from the same tissues. This demonstrated approximately equal levels of the two transcripts in normal tissues whereas the A-mRNA was the most abundant isoform in the cancer cell lines investigated. Approximately 4.5 kb of the 5' flanking region of the rat ER (rER) gene were sequenced. Sequence analysis and PCR experiments suggested that the promoter organization of the rat and human ER genes is only partially conserved which might indicate species-specific differences in the regulation of ER expression. In conclusion, this work suggests tissue-specific alternative promoter usage as a mechanism in the regulation of human and rat ER gene expression.
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Affiliation(s)
- K Grandien
- Department of Medical Nutrition, Karolinska Institute, NOVUM, Huddinge, Sweden
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13
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Bassuk AG, Leiden JM. A direct physical association between ETS and AP-1 transcription factors in normal human T cells. Immunity 1995; 3:223-37. [PMID: 7648395 DOI: 10.1016/1074-7613(95)90092-6] [Citation(s) in RCA: 153] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The Ets and AP-1 families of transcription factors bind distinct DNA elements and subserve diverse functions in multiple lymphoid and nonlymphoid cell types. Functionally important Ets and AP-1 binding sites have been identified in a large number of enhancer elements, suggesting important cooperative interactions between these two families of transcription factors. In this report, we have demonstrated a direct physical interaction between Ets and AP-1 proteins both in vitro and in activated human T cells. This interaction is mediated by the binding of the basic domain of Jun to the Ets domain of Ets proteins. Jun, in association with Ets, is capable of interacting with Fos family members to form a trimolecular protein complex. The physical association between Ets-1 and AP-1 proteins is required for the transcriptional activity of enhancer elements containing adjacent Ets and AP-1 binding sites. We conclude that direct physical interactions between Ets and AP-1 transcription factors play an important role in regulating mammalian gene expression.
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Affiliation(s)
- A G Bassuk
- Department of Medicine, University of Chicago, Illinois 60637, USA
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14
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Ribeiro A, Brown A, Lee KA. An in vivo assay for members of the cAMP response element-binding protein family of transcription factors. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(18)47398-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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15
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Wollberg P, Söderqvist H, Nelson B. Mitogen activation of human peripheral T lymphocytes induces the formation of new cyclic AMP response element-binding protein nuclear complexes. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)32080-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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16
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Lee KA, Masson N. Transcriptional regulation by CREB and its relatives. BIOCHIMICA ET BIOPHYSICA ACTA 1993; 1174:221-33. [PMID: 8373801 DOI: 10.1016/0167-4781(93)90191-f] [Citation(s) in RCA: 149] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- K A Lee
- Imperial Cancer Research Fund, Clare Hall Laboratories, Potters Bar, UK
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17
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Affiliation(s)
- T Ny
- Department of Cell and Molecular Biology, University of Umeå, Sweden
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18
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Ransone LJ, Kerr LD, Schmitt MJ, Wamsley P, Verma IM. The bZIP domains of Fos and Jun mediate a physical association with the TATA box-binding protein. Gene Expr 1993; 3:37-48. [PMID: 7685215 PMCID: PMC6081620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/1992] [Accepted: 01/22/1993] [Indexed: 01/26/2023]
Abstract
Fos and Jun oncoproteins form a complex that regulates transcription from promoters containing AP-1 binding sites. These two proteins, like other transcriptional activators, are likely to stimulate transcription through direct and/or indirect interactions with members of the basal transcriptional machinery. The ability of c-Fos and c-Jun proteins to interact directly with the TATA box-binding protein (TBP), the general transcription factor required for initiating the assembly of transcription complexes, was investigated. Using co-immunoprecipitation and protein-protein association assays, we show that both c-Fos and c-Jun bind specifically and stably to TBP. Mutational analysis demonstrates that both the basic region and leucine zipper domains of c-Fos and c-Jun are necessary and sufficient for stable association with TBP. A 51-residue region from the conserved C-terminal region of TBP, previously shown to be the binding site for the viral activator protein E1A, interacts with c-Fos and c-Jun proteins. We propose that c-Fos and c-Jun proteins function as transcriptional activators, in part by recruiting TBP to form complexes to initiate RNA synthesis.
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Affiliation(s)
- L J Ransone
- Molecular Biology and Virology Laboratory, Salk Institute, San Diego, CA 85800
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19
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Schindler U, Terzaghi W, Beckmann H, Kadesch T, Cashmore AR. DNA binding site preferences and transcriptional activation properties of the Arabidopsis transcription factor GBF1. EMBO J 1992; 11:1275-89. [PMID: 1563344 PMCID: PMC556575 DOI: 10.1002/j.1460-2075.1992.tb05171.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
The G-box is a cis-acting element found within the promoters of many plant genes where it mediates expression in response to a variety of different stimuli. This palindromic DNA motif (CCACGTGG) is composed of two identical half sites, the base pairs of which we have numbered -4 to +4 (numbering from 5' to 3'). Both half sites are involved in the binding of the bZIP protein GBF1, a member of the GBF family of Arabidopsis thaliana. Here we demonstrate using the random binding site selection method that GBF1 interacts with, in addition to the palindromic G-box, other DNA motifs that fall into seven distinct groups. All groups share the ACGT core sequence, common to most DNA motifs bound by plant bZIP proteins so far characterized. Our studies demonstrate that a high affinity GBF1 binding site is further defined by the following two parameters: first, all sites contain a G residue at position +3 (as in ACGTG) and secondly, only certain base pair combinations are allowed at positions -4, -3 and +4. Two of the identified groups (TGACGTGG and TGACGTGT) contain the base pairs TG at positions -4 and -3 and hence resemble the binding sites of another class of plant bZIP proteins (TGACGT/C binding proteins). However, GBF1 only interacts with the TGACGT sequence if the two 3' distal nucleotides (positions +3 and +4) are occupied by GG or GT. These data define the differences between a G-box binding protein and TGACGT/C binding proteins. The N-terminal domain of GBF1 is defined by a high proline content. Such regions were also identified in proteins related to GBF1. We demonstrate that this N-terminal proline-rich domain of GBF1, when fused to a heterologous DNA binding domain, stimulates transcription in both plant protoplasts and mammalian cells. These extensive DNA binding studies and the characterization of the GBF1 activation domain will facilitate both the identification of regulatory elements and the in vivo function of GBF1.
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Affiliation(s)
- U Schindler
- Plant Science Institute, University of Pennsylvania, Philadelphia 19104
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Bengal E, Ransone L, Scharfmann R, Dwarki VJ, Tapscott SJ, Weintraub H, Verma IM. Functional antagonism between c-Jun and MyoD proteins: a direct physical association. Cell 1992; 68:507-19. [PMID: 1310896 DOI: 10.1016/0092-8674(92)90187-h] [Citation(s) in RCA: 343] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The product of the proto-oncogene Jun inhibits myogenesis. Constitutive expression of Jun in myoblasts interferes with the expression and the function of MyoD protein. In transient transfection assays Jun inhibits transactivation of the MyoD promoter, the muscle creatine kinase enhancer, and a reporter gene linked to MyoD DNA-binding sites. Conversely, MyoD suppresses the transactivation by Jun of genes linked to an AP-1 site. We demonstrate that both in vivo and in vitro MyoD and Jun proteins physically interact. Mutational analysis suggests that this interaction occurs via the leucine zipper domain of Jun and the helix-loop-helix region of MyoD.
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Affiliation(s)
- E Bengal
- Molecular Biology and Virology Laboratory, Salk Institute, San Diego, California 92186-5800
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Kooistra T, Bosma PJ, Toet K, Cohen LH, Griffioen M, van den Berg E, le Clercq L, van Hinsbergh VW. Role of protein kinase C and cyclic adenosine monophosphate in the regulation of tissue-type plasminogen activator, plasminogen activator inhibitor-1, and platelet-derived growth factor mRNA levels in human endothelial cells. Possible involvement of proto-oncogenes c-jun and c-fos. ARTERIOSCLEROSIS AND THROMBOSIS : A JOURNAL OF VASCULAR BIOLOGY 1991; 11:1042-52. [PMID: 1648385 DOI: 10.1161/01.atv.11.4.1042] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Activation of protein kinase C leads to a strong induction of tissue-type plasminogen activator (t-PA) expression in endothelial cells. Using endothelial cells from human umbilical vein (HUVECs) and human aorta (HAECs), we have studied this regulation of t-PA and its inhibitor, plasminogen activator inhibitor-1 (PAI-1), at the mRNA level and have compared their induction with the expression of platelet-derived growth factors A and B (PDGF-A and PDGF-B) and the proto-oncogenes c-jun and c-fos. Treatment of HUVECs with exogenous bacterial phospholipase C or the synthetic diacylglycerol 1-oleoyl-2-acetylglycerol led to a threefold and a twofold increase, respectively, in t-PA concentrations in 24-hour-conditioned medium. Similarly, the more stable protein kinase C activator 4 beta-phorbol-12-myristate-13-acetate (PMA) caused about a 10-fold increase in t-PA antigen levels. This effect of PMA is maximal between 8 and 16 hours at a concentration of 10 nM and is fully accounted for by parallel increases in t-PA mRNA levels. An increase in intracellular cyclic adenosine monophosphate levels by forskolin (10 microM) slightly diminished t-PA expression but further enhanced the PMA-induced increases in t-PA synthesis and mRNA levels by at least twofold. PMA also enhanced the mRNA levels of two other important endothelium-expressed genes, PDGF-A and PDGF-B, with a time profile similar to that of t-PA, with peak values about fivefold higher than control values. Forskolin did not further stimulate this PMA-induced PDGF expression in HUVECs, which suggests a regulatory mechanism different from that of t-PA. Qualitatively very similar induction patterns of t-PA, PDGF-A, and PDGF-B were seen with HAECs. In contrast to t-PA and PDGF, PAI-1 mRNA and antigen levels increased only slightly after PMA treatment of HUVECs or HAECs; forskolin alone or in combination with PMA diminished the expression of PAI-1. The induction of t-PA mRNA by PMA was dependent on protein synthesis and was preceded by a strong transient increase in c-jun and c-fos mRNA levels; the induction of c-fos but not of c-jun was potentiated by forskolin. Because the products of these two proto-oncogenes form dimeric complexes for which specific binding sites are present in the t-PA promoter region, they may mediate the protein kinase C-dependent increase in t-PA gene expression, including the stimulating action of cyclic adenosine monophosphate.
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Affiliation(s)
- T Kooistra
- Gaubius Laboratory IVVO-TNO, Leiden, The Netherlands
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