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Prins JB, Langerak AW, Dirks RP, Van der Linden-Van Beurden CA, De Laat PA, Bloemers HP, Versnel MA. Identification of regulatory sequences in the promoter of the PDGF B-chain gene in malignant mesothelioma cell lines. BIOCHIMICA ET BIOPHYSICA ACTA 1996; 1317:223-32. [PMID: 8988239 DOI: 10.1016/s0925-4439(96)00060-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Platelet-derived growth factor (PDGF) B-chain mRNA is readily detectable in malignant mesothelioma (MM) cell lines, but not in normal mesothelial (NM) cell lines. The high affinity receptor for PDGF B-chain dimers, the PDGF beta-receptor, is expressed in MM cell lines. NM cell lines predominantly express the PDGF alpha-receptor. Coexpression of the PDGF beta-receptor and its ligand may lead to an autocrine growth stimulating loop in the malignant cell type. In nuclear run off experiments, PDGF B-chain mRNA was detectable in MM cells only, indicating an increased level of transcription in this cell type. The proximal promoter of the PDGF B-chain gene contains DNaseI hypersensitive (DH) sites and mediates reporter gene activation in both normal and malignant cells. Nuclear proteins, extracted from both cell types, interact with DNA sequences within the proximal promoter around bp-64 to -61 relative to the transcription start site. Electrophoretic mobility shift assays (EMSAs) indicate that these factors are more abundantly present in the malignant than in the normal cell type. A DH site around -9.9 kb was found in both cell types. When tested in CAT assays, this region exerted a stimulatory effect on transcription in malignant cells. The elevated level of transcription of the PDGF B-chain gene in malignant cells may well be the result of interaction of regulatory sites in the proximal promoter and an enhancing element located at -9.9 kb from the transcription start site.
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Affiliation(s)
- J B Prins
- Department of Immunology, Erasmus University Rotterdam, The Netherlands
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2
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Scarpati EM, DiCorleto PE. Identification of a thrombin response element in the human platelet-derived growth factor B-chain (c-sis) promoter. J Biol Chem 1996; 271:3025-32. [PMID: 8621696 DOI: 10.1074/jbc.271.6.3025] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Thrombin is a coagulation system protease that also serves as a potent stimulator of gene expression in several cell types, including endothelial cells (EC). We and others have previously demonstrated that the transcription of platelet-derived growth factor (PDGF) B-chain (c-sis) by EC is stimulated severalfold by thrombin. Here we examine the molecular mechanism of this regulatory process using bovine aortic EC transiently transfected with a vector containing the chloramphenicol acetyltransferase (CAT) gene under the control of a 400-base pair fragment of the human PDGF B-chain promoter. Thrombin treatment of these cells caused a severalfold increase in CAT expression. Deletion analysis and site-directed mutagenesis revealed that the region spanning nucleotides -61 to -53 from the transcription initiation site (referred to as the thrombin response, or ThR, region) was critical for the transcriptional response to thrombin. Electrophoretic mobility shift assays with an oligonucleotide corresponding to the region -64 to -44, which contained the ThR region, led to the identification of a thrombin-inducible nuclear factor (TINF) in extracts from thrombin-treated, but not control, EC. TINF was formed as early as 40 min post-thrombin treatment, persisted for at least 7 h, but was no longer present after 24 h. TINF appeared in the absence of de novo protein synthesis. The ThR region consists of a repeat of a CCACCC element in an ABBA configuration, which, based on mutation analysis and transfection assays, appears to be critical in mediating thrombin stimulation of the PDGF B-chain gene. The conservation of the ThR region in the promoter of the PDGF B-chain among three species (human, feline, and murine) further supports the importance of this region as a cis-acting regulatory element.
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Affiliation(s)
- E M Scarpati
- Department of Cell Biology, Research Institute of The Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA
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3
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Abstract
PDGF is an important polypeptide growth factor that plays an essential role during early vertebrate development and is associated with tissue repair and wound healing in the adult vertebrate. Moreover, PDGF is thought to play a role in a variety of pathological phenomena, such as cancer, fibrosis and atherosclerosis. PDGF is expressed as a dimer of A and/or B chains, the precursors of which are encoded by two single copy genes. Although the PDGF genes are expressed coordinately in a number of cell types, they are independently expressed in a majority of cell types. The expression of either PDGF gene can be affected by very diverse extracellular stimuli and the type of response is dependent on the cell type that is exposed to the stimulus. Expression of the PDGF chains can be modulated at every imaginable level: by regulating accessibility of the transcription start site, by varying the transcription initiation rate, by using alternative transcription start sites, by alternative splicing, by using alternative polyadenylation signals, by varying mRNA decay rates, by regulating efficiency of translation, by protein modification, and by regulating secretion. Even upon secretion, the activity of PDGF can be modulated by non-specific or specific PDGF-binding proteins. This review provides an overview of the cell types in which the PDGF genes are expressed, of the factors that are known to affect the expression of PDGF, and of the various levels at which the expression of PDGF genes can be regulated.
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Affiliation(s)
- R P Dirks
- Department of Molecular Biology, University of Nijmegen, The Netherlands
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4
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Dirks RP, Onnekink C, Jansen HJ, de Jong A, Bloemers HP. A novel human c-sis mRNA species is transcribed from a promoter in c-sis intron 1 and contains the code for an alternative PDGF B-like protein. Nucleic Acids Res 1995; 23:2815-22. [PMID: 7659502 PMCID: PMC307116 DOI: 10.1093/nar/23.15.2815] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The human platelet-derived growth factor (PDGF) B chain precursor is usually translated from a 3.5 kb c-sis/PDGF B gene transcript. The first exon of the c-sis/gene contains the code for the signal peptide of the PDGF B chain precursor, preceded by a 1 kb long untranslated sequence with potent translation inhibitory activity. In this paper we show that a novel 2.6 kb c-sis mRNA present in the human choriocarcinoma cell line JEG-3 initiates at an alternative exon 1, which we refer to as exon 1a. The 90 bp long exon 1a is located in the center of the first intron of the gene. It coincides with a very pronounced DNase-I-hypersensitive site and is preceded by a functional promoter. Of the three ATG codons present in exon 1a, the third one perfectly matches the criteria of a consensus start codon. It initiates an open reading frame that is continuous with the code for the PDGF B chain precursor but lacks the code for a signal peptide. We conclude that this novel 2.6 kb c-sis mRNA species lacks the strong translation inhibitory potential of the regular exon 1 and contains the code for a PDGF B-like protein that may be targeted to the cell nucleus.
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Affiliation(s)
- R P Dirks
- Department of Biochemistry, University of Nijmegen, The Netherlands
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5
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Bernstein J, Shefler I, Elroy-Stein O. The translational repression mediated by the platelet-derived growth factor 2/c-sis mRNA leader is relieved during megakaryocytic differentiation. J Biol Chem 1995; 270:10559-65. [PMID: 7737991 DOI: 10.1074/jbc.270.18.10559] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Expression of the platelet-derived growth factor 2/c-sis gene is highly restricted and controlled at multiple levels. Its structured mRNA leader, which is unusually long (1022 nucleotides), serves as a potent translational inhibitor. One of the sites of PDGF2 synthesis is megakaryocytes, implying that PDGF2 translation efficiency is modulated during megakaryocytic differentiation. To study the role of the mRNA leader as a translational cis-modulator, the hybrid T7/vaccinia cytoplasmic expression system was used to disconnect between determinants controlling transcription, alternative splicing, and mRNA stability from those controlling translation. Chimeric transcripts in which the human PDGF2/c-sis mRNA leader positioned in frame upstream of a reporter gene were used to determine whether the mRNA leader can confer variable translational efficiencies during differentiation. It is demonstrated that there is a time window during megakaryocytic differentiation of K562 cells in which the strong translational inhibition by PDGF2/c-sis mRNA leader is relieved. The time course of the translational repression relief is similar to that of PDGF2/c-sis transcriptional induction during the differentiation process. A 179-nucleotides CG-rich fragment immediately upstream of the initiator AUG codon is necessary for coffering stringent modulation of the translational efficiency. In NIH3T3 overexpressing translation initiation factor eIF4E, the inhibitory effect of the mRNA leader of c-sis is not relieved, suggesting that the changes in the translational machinery during megakaryocytic differentiation are beyond eIF4E activity. The possible involvement of a 5'-end-independent translational mechanism is discussed.
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Affiliation(s)
- J Bernstein
- Department of Cell Research and Immunology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Israel
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6
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Dirks RP, Jansen HJ, van Gerven B, Onnekink C, Bloemers HP. In vivo footprinting and functional analysis of the human c-sis/PDGF B gene promoter provides evidence for two binding sites for transcriptional activators. Nucleic Acids Res 1995; 23:1119-26. [PMID: 7739890 PMCID: PMC306819 DOI: 10.1093/nar/23.7.1119] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
By in vivo DMS footprint and reporter gene analyses we identified two transcription factor binding sites in the human c-sis/PDGF B gene promoter. The low basal activity of the PDGF B promoter in HeLa and undifferentiated K562 cells, which express low PDGF B mRNA levels, and in PC3 cells, which express a high PDGF B mRNA level, results from binding of a weak transcriptional activator between positions -64 and -61 relative to the transcription start site. Cytotrophoblast-like JEG-3 cells, which do not express the 3.5 kb PDGF B mRNA, contain a transcriptional activator directed at the -64/-61 sequence, but DNA methylation may render the endogenous promoter inaccessible to this activator. A CCACCCAC element at position -61/-54 was identified as the in vivo binding site for a strong transcriptional activator in phorbol ester-treated megakaryocytic K562 cells, which express a high PDGF B mRNA level. Primary human fibroblasts, which do not transcribe the PDGF B gene, contain a transcriptional activator that recognizes an element between positions -60 and -45 but does not bind to the endogenous unmethylated promoter. Our results show that the complex expression pattern of the human PDGF B gene involves the cell type-specific expression of weak and strong transcriptional activators and regulation of promoter accessibility to these factors.
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Affiliation(s)
- R P Dirks
- Department of Biochemistry, University of Nijmegen, The Netherlands
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7
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SIS/PDGF-B promoter isolation and characterization of regulatory elements necessary for basal expression of the SIS/PDGF-B gene in U2-OS osteosarcoma cells. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(19)61954-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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8
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Dirks RP, Jansen HJ, Gerritsma J, Onnekink C, Bloemers HP. Localization and functional analysis of DNase-I-hypersensitive sites in the human c-sis/PDGF-B gene transcription unit and its flanking regions. EUROPEAN JOURNAL OF BIOCHEMISTRY 1993; 211:509-19. [PMID: 8436112 DOI: 10.1111/j.1432-1033.1993.tb17577.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
We studied the regulation of the expression of the human c-sis/PDGF-B gene in the following panel of cell lines: K562 cells, in which expression is inducible by phorbol esters; cytotrophoblast-derived cell lines JEG-3 and JAR; carcinoma-derived cell lines PC3, T24 and HeLa, which show extensive differences in c-sis mRNA content; dermal fibroblasts, which do not express the gene. We demonstrate that the wide variety of levels of c-sis mRNA in these cells is mainly determined at the transcription level. Extensive gene rearrangements or amplifications, or significant differences in the stability of the c-sis transcript could not be found. In fibroblasts and placenta cell lines, inaccessibility of the c-sis promoter, rather than the absence of transcription factors that activate it, inhibits expression of the endogenous gene. Examination of the chromatin structure of the transcription unit and immediate flanking regions revealed several cell-type-specific DNase-I-hypersensitivity (DH) sites. Functional analysis of genomic fragments harbouring one or more DH sites showed the presence of negative regulatory elements within intron 1, and of an activating element downstream of the gene. A DH site, located immediately downstream of the promoter in dermal fibroblasts, may regulate accessibility of the promoter by means of specific nucleosome phasing.
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Affiliation(s)
- R P Dirks
- Department of Biochemistry, University of Nijmegen, The Netherlands
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9
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Abstract
The carboxyl terminus of the protein encoded by the c-MYC protooncogene has similarity to the helix-loop-helix family of DNA-binding proteins and recognizes a six-nucleotide-long DNA sequence. We have used in vitro-translated c-MYC protein to further define its DNA-binding specificity. The hexanucleotide originally identified is necessary for DNA binding by c-MYC, but not sufficient; the c-MYC target site is a 12-nucleotide-long palindrome. This site is present within regulatory regions of genes that are expressed during cell growth. Point mutations within the helix-loop-helix motif of c-MYC abolish DNA-binding and transforming activities, indicating that c-MYC acts as a DNA-binding protein to transform cells. c-MYC may transform cells by activating transcription of genes required for cell division.
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Affiliation(s)
- T D Halazonetis
- Department of Cancer Research, Merck Sharp & Dohme Research Laboratories, West Point, PA 19486
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10
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Takimoto Y, Wang ZY, Kobler K, Deuel TF. Promoter region of the human platelet-derived growth factor A-chain gene. Proc Natl Acad Sci U S A 1991; 88:1686-90. [PMID: 1848007 PMCID: PMC51089 DOI: 10.1073/pnas.88.5.1686] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The platelet-derived growth factor (PDGF) A- and B-chain genes are widely expressed in mammalian tissues and their homodimeric gene products appear to regulate the autocrine growth of both normal and transformed cells. In this study, we analyzed the 5' flanking sequences of the human PDGF A-chain gene to seek elements important to regulating its transcription. The promoter region was exceptionally G + C-rich and contained a "TATA box" but no "CAAT box." The transcription start site was identified 845 base pairs 5' to the translation initiation site by S1 nuclease mapping and by primer extension. Both in vitro transcription and transient expression of the chloramphenicol acetyltransferase gene linked to the PDGF A-chain 5' flanking sequences established that the putative promoter region was active, and RNase H mapping established that the three characteristic mRNAs (1.9, 2.3, and 2.8 kilobases) used the same transcription start site, which was used in normal endothelial cells and in two human tumor cell lines that express high levels of A-chain transcripts. The results established an exceptionally G + C-rich promoter region and a single transcription start site active for each of the three mRNAs of the PDGF A-chain gene. DNA sites of potential importance in mediating the activation of the PDGF A-chain gene in normal cells and in transformed cell lines expressing high levels of PDGF A chain were identified.
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Affiliation(s)
- Y Takimoto
- Department of Medicine, Jewish Hospital, Washington University Medical Center, St. Louis, MO 63110
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11
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Doucet JP, Squinto SP, Bazan NG. Fos-jun and the primary genomic response in the nervous system. Possible physiological role and pathophysiological significance. Mol Neurobiol 1990; 4:27-55. [PMID: 2127531 DOI: 10.1007/bf02935584] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- J P Doucet
- Department of Biochemistry and Molecular Biology, Louisiana State University Medical Center, New Orleans 70112
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12
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Functional identification of regulatory elements within the promoter region of platelet-derived growth factor 2. Mol Cell Biol 1989. [PMID: 2651898 DOI: 10.1128/mcb.9.2.396] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human platelet-derived growth factor (PDGF) is composed of two polypeptide chains, PDGF-1 and PDGF-2, the human homolog of the v-sis oncogene. Deregulation of PDGF-2 expression can confer a growth advantage to cells possessing the cognate receptor and, thus, may contribute to the malignant phenotype. We investigated the regulation of PDGF-2 mRNA expression during megakaryocytic differentiation of K562 cells. Induction by 12-O-tetradecanoylphorbol-13-acetate (TPA) led to a greater than 200-fold increase in PDGF-2 transcript levels in these cells. Induction was dependent on protein synthesis and was not enhanced by cycloheximide exposure. In our initial investigation of the PDGF-2 promoter, a minimal promoter region, which included sequences extending only 42 base pairs upstream of the TATA signal, was found to be as efficient as 4 kilobase pairs upstream of the TATA signal in driving expression of a reporter gene in uninduced K562 cells. We also functionally identified different regulatory sequence elements of the PDGF-2 promoter in TPA-induced K562 cells. One region acted as a transcriptional silencer, while another region was necessary for maximal activity of the promoter in megakaryoblasts. This region was shown to bind nuclear factors and was the target for trans-activation in normal and tumor cells. In one tumor cell line, which expressed high PDGF-2 mRNA levels, the presence of the positive regulatory region resulted in a 30-fold increase in promoter activity. However, the ability of the minimal PDGF-2 promoter to drive reporter gene expression in uninduced K562 cells and normal fibroblasts, which contained no detectable PDGF-2 transcripts, implies the existence of other negative control mechanisms beyond the regulation of promoter activity.
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13
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Pech M, Rao CD, Robbins KC, Aaronson SA. Functional identification of regulatory elements within the promoter region of platelet-derived growth factor 2. Mol Cell Biol 1989; 9:396-405. [PMID: 2651898 PMCID: PMC362614 DOI: 10.1128/mcb.9.2.396-405.1989] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Human platelet-derived growth factor (PDGF) is composed of two polypeptide chains, PDGF-1 and PDGF-2, the human homolog of the v-sis oncogene. Deregulation of PDGF-2 expression can confer a growth advantage to cells possessing the cognate receptor and, thus, may contribute to the malignant phenotype. We investigated the regulation of PDGF-2 mRNA expression during megakaryocytic differentiation of K562 cells. Induction by 12-O-tetradecanoylphorbol-13-acetate (TPA) led to a greater than 200-fold increase in PDGF-2 transcript levels in these cells. Induction was dependent on protein synthesis and was not enhanced by cycloheximide exposure. In our initial investigation of the PDGF-2 promoter, a minimal promoter region, which included sequences extending only 42 base pairs upstream of the TATA signal, was found to be as efficient as 4 kilobase pairs upstream of the TATA signal in driving expression of a reporter gene in uninduced K562 cells. We also functionally identified different regulatory sequence elements of the PDGF-2 promoter in TPA-induced K562 cells. One region acted as a transcriptional silencer, while another region was necessary for maximal activity of the promoter in megakaryoblasts. This region was shown to bind nuclear factors and was the target for trans-activation in normal and tumor cells. In one tumor cell line, which expressed high PDGF-2 mRNA levels, the presence of the positive regulatory region resulted in a 30-fold increase in promoter activity. However, the ability of the minimal PDGF-2 promoter to drive reporter gene expression in uninduced K562 cells and normal fibroblasts, which contained no detectable PDGF-2 transcripts, implies the existence of other negative control mechanisms beyond the regulation of promoter activity.
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Affiliation(s)
- M Pech
- Laboratory of Cellular and Molecular Biology, National Cancer Institute, Bethesda, Maryland 20892
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14
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Sariban E, Sitaras NM, Antoniades HN, Kufe DW, Pantazis P. Expression of platelet-derived growth factor (PDGF)-related transcripts and synthesis of biologically active PDGF-like proteins by human malignant epithelial cell lines. J Clin Invest 1988; 82:1157-64. [PMID: 2844850 PMCID: PMC442665 DOI: 10.1172/jci113712] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Human malignant epithelial cell lines were analyzed for expression of platelet-derived growth factor (PDGF) genes. Of the 12 cell lines tested, 9, derived from breast, lung, gastric, and ovarian carcinomas, were found to express both PDGF-1 and PDGF-2 genes. The levels of both PDGF-1 and PDGF-2 transcripts were superinduced when these cells were treated with cycloheximide, an inhibitor of protein synthesis. These cells also released an activity that in studies with BALB-c/3T3 cells, inhibited binding of 125I-labeled PDGF and stimulated incorporation of [3H]thymidine. This stimulating activity was inhibited after reduction of the conditioned media by mercaptoethanol or after preincubation with antibodies to PDGF. Moreover, this activity was not affected by heat treatment. Immunoprecipitation studies revealed that breast, lung, and gastric carcinoma cells produced PDGF-like proteins that migrated as 30- and 32-kD species under nonreducing conditions and as 15- and 16-kD species under reducing conditions. In contrast, malignant cells of ovarian origin produced 14-16-kD PDGF-like proteins that were unchanged in mobility after reduction. As PDGF receptors were not detected on these malignant epithelial cells, the production of PDGF-like proteins may affect other cells in the microenvironment by paracrine mechanisms and may contribute to excessive cell proliferation, inflammatory reactions, and connective tissue remodeling seen in certain carcinomas.
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Affiliation(s)
- E Sariban
- Laboratory of Clinical Pharmacology, Dana-Farber Cancer Institute, Boston, MA 02115
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15
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Bonthron D, Orkin SH. The human von Willebrand factor gene. Structure of the 5' region. EUROPEAN JOURNAL OF BIOCHEMISTRY 1988; 171:51-7. [PMID: 2828057 DOI: 10.1111/j.1432-1033.1988.tb13757.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Von Willebrand factor (vWF) is a multimeric glycoprotein product of endothelial cells and platelets, that is important for normal hemostasis. Recently the complete primary structure of the vWF precursor was deduced from cloned complementary DNAs (cDNAs). To approach the analysis of DNA elements that mediate tissue-specific expression, we have characterized the region of the human vWF gene surrounding the transcriptional initiation site, and including the first five exons. The putative vWF promoter region includes an (A + T)-rich 'TATA'-like element approximately 30 bp upstream of the transcription start site, but no CCAAT or 'GC' box elements (typical motifs of other promoters). A (GT)n repeat element of uncertain significance is located about 650 bp farther upstream. The DNA sequence of the 5' flanking region suggests the presence of potentially novel elements involved in regulation of the restricted expression of vWF.
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Affiliation(s)
- D Bonthron
- Division of Hematology/Oncology, Children's Hospital, Dana-Farber Cancer Institute, Boston, Massachusetts
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16
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Ratner L, Thielan B, Collins T. Sequences of the 5' portion of the human c-sis gene: characterization of the transcriptional promoter and regulation of expression of the protein product by 5' untranslated mRNA sequences. Nucleic Acids Res 1987; 15:6017-36. [PMID: 3627977 PMCID: PMC306065 DOI: 10.1093/nar/15.15.6017] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The c-sis gene encodes the B polypeptide chain of platelet-derived growth factor (PDGF), and is expressed in a number of normal and pathological conditions. In order to study the control of synthesis of the human c-sis product, we have initiated a study of two regions of this genetic locus which regulate transcription and translation. A clone of the 5' portion of the gene was obtained which included 1361 nucleotides upstream of the RNA initiation site. Transcriptional promoter activity of this region was demonstrated in normal and transformed cells using a plasmid with the sequences upstream of the c-sis RNA initiation site fused to an indicator gene, chloramphenicol acetyl transferase. Experiments were also performed to identify other possible regulatory regions of the c-sis gene. These data demonstrated that a portion of the c-sis first exon encoding the 5' untranslated region of the c-sis mRNA inhibited synthesis of the PDGF B product in vitro. These results define regions of the c-sis gene whose activity may be important in the regulation of transcription and translation under normal conditions and in the pathogenesis several human diseases.
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17
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Abstract
Primer extension footprinting was used to probe late simian virus 40 regulatory elements in intact infected cell nuclei. Specific protection was observed over the viral "GC-box" transcription elements. The participation of the bound templates in gene activation is addressed by quantitation that shows that their abundance greatly exceeds that of transcription complexes but is comparable to that of open chromatin.
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18
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Ferrari S, Calabretta B, deRiel JK, Battini R, Ghezzo F, Lauret E, Griffin C, Emanuel BS, Gurrieri F, Baserga R. Structural and functional analysis of a growth-regulated gene, the human calcyclin. J Biol Chem 1987. [DOI: 10.1016/s0021-9258(18)47567-9] [Citation(s) in RCA: 99] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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19
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Van den Ouweland AM, van Groningen JJ, Hendriksen PJ, Bloemers HP, Van de Ven WJ. Nucleotide sequence of the DNA region immediately upstream of the human c-sis proto-oncogene. Nucleic Acids Res 1987; 15:4349. [PMID: 3295777 PMCID: PMC340852 DOI: 10.1093/nar/15.10.4349] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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20
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21
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Buchanan RL, Gralla JD. Factor interactions at simian virus 40 GC-box promoter elements in intact nuclei. Mol Cell Biol 1987; 7:1554-8. [PMID: 3037329 PMCID: PMC365246 DOI: 10.1128/mcb.7.4.1554-1558.1987] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Primer extension footprinting was used to probe late simian virus 40 regulatory elements in intact infected cell nuclei. Specific protection was observed over the viral "GC-box" transcription elements. The participation of the bound templates in gene activation is addressed by quantitation that shows that their abundance greatly exceeds that of transcription complexes but is comparable to that of open chromatin.
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22
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Van den Ouweland AM, Van Groningen JJ, Schalken JA, Van Neck HW, Bloemers HP, Van de Ven WJ. Genetic organization of the c-sis transcription unit. Nucleic Acids Res 1987; 15:959-70. [PMID: 3822831 PMCID: PMC340501 DOI: 10.1093/nar/15.3.959] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The structure and genetic organization of the transcription unit of the c-sis proto-oncogene was determined. Comparative nucleotide sequence analysis of the exon sequences of feline and human c-sis revealed a very high degree of homology. The cap site as well as the poly(A)-addition site of the sis transcript of each species was identified and found in similar positions. An insert of 4 amino acids was found in the deduced translational product of feline c-sis and it was located at the amino-terminus of the region that constituted the platelet-derived growth factor domain. An insert of 149 bp present at the 5' end of exon 7 of human c-sis but absent in the simian sarcoma virus v-sis oncogene was also present in the feline c-sis proto-oncogene.
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