Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.30.1 (S1 nuclease)
 3,660 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Transcription of the platelet-derived growth factor (PDGF) A-chain gene is activated in cells exposed to growth factors. We now have identified a homopurine/homopyrimidine domain in the promoter region of the PDGF A-chain gene that exhibits S1 nuclease sensitivity in vitro and that contains a novel binding site (5'-TCCTCCTCCTCCTC-3') for the growth factor inducible transcription factor EGR-1 as demonstrated in gel mobility shift assays. Sequences similar to this novel EGR-1 binding site were observed also in five growth-related genes and shown to bind to EGR-1 in competition assays, suggesting that EGR-1 may influence the transcriptional regulation of these growth-related genes.
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PMID:An S1 nuclease-sensitive homopurine/homopyrimidine domain in the PDGF A-chain promoter contains a novel binding site for the growth factor-inducible protein EGR-1. 141 65

Homodimers of the platelet-derived growth factor (PDGF) A-chain are strong mitogens for cells of mesenchymal origin. Differences in the levels of expression of the PDGF A-chain gene have been reported in both normal and transformed cell lines, suggesting that transcription of the PDGF A-chain gene is highly regulated. We have now identified two S1-hypersensitive sites which flank a 13-base pair oligo(dG).oligo(dC) sequence located 70-82 base pairs upstream of the transcription initiation site. Three lines of evidence suggest that these S1-sensitive sites contribute to optimum promoter activity. Nuclear protein(s) binding to these sites were detected in gel mobility shift assays. Deletion of the S1-sensitive sites results in a 2-3-fold decrease in the transcriptional activity and eliminated sensitivity to S1 nuclease. Deletions in the oligo(dG).oligo(dC) motif also eliminated sensitivity to S1 and resulted in a 2.5-fold decrease of the promoter activity in the stable transfection assays. The results suggest that the highly G+C-rich region in the PDGF A-chain gene promoter locally induces the formation of non-B-form DNA under torsional stress which appears to be important in the transcriptional regulation of the PDGF A-chain gene in vivo.
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PMID:Modulation of transcription of the platelet-derived growth factor A-chain gene by a promoter region sensitive to S1 nuclease. 151 41

Levels of expression of the platelet-derived growth factor (PDGF) A-chain gene differ significantly in normal and transformed cells. We have identified an S1 nuclease-sensitive site in a GC box located at -55 to -72 in the PDGF A-chain promoter region. We now demonstrate that a 24-base, G-rich complementary oligonucleotide anneals specifically to the C-rich strand of the GC box and protects the GC box from nicking by S1 nuclease whereas the C-rich complementary oligonucleotide and its double-stranded counterpart do not. In transient transfection assays, expression of the PDGF A-chain gene is sharply reduced by deletions within the GC box or if the 24-base G-rich complementary oligonucleotide is preincubated with the promoter construct prior to transfection. The data suggest that the GC box of the PDGF A-chain gene may promote a non-B-form DNA structure, which is recognized by S1 nuclease and which anneals to a short complementary G-rich oligonucleotide. The data also suggest that this non-B-form DNA is important for efficient transcription of PDGF A-chain gene.
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PMID:Binding of single-stranded oligonucleotides to a non-B-form DNA structure results in loss of promoter activity of the platelet-derived growth factor A-chain gene. 161 66

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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PMID:Promoter region of the human platelet-derived growth factor A-chain gene. 184 7

cyr61 is an immediate early gene that is transcriptionally activated in 3T3 fibroblasts by serum, platelet-derived growth factor, fibroblast growth factor, and the tumor promoter TPA with kinetics similar to the induction of c-fos. cyr61 encodes a secreted protein that is associated with the cell surface and the extracellular matrix, and may play a role in cell-cell communication. We report here the complete nucleotide sequence of the mouse cyr61 gene, which contains four short introns. The transcription start site was mapped by S1 nuclease and primer extension analyses. A 2 kb 5' flanking DNA fragment functions as a serum-inducible promoter. This DNA fragment contains a poly(CA) sequence that can adopt the Z DNA form. In addition, it contains a sequence that resembles the serum response element (SRE) originally identified in the c-fos promoter. We show that deletion of the cry61 SRE-like sequence abrogates serum inducibility. Furthermore, this SRE-like sequence is sufficient to confer serum and growth factor inducibility when linked to a basal promoter, and binds the 67 kD serum response factor in vitro. We conclude that the cyr61 SRE functions as a serum response element and may account for the coordinate activation of cyr61 and c-fos.
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PMID:Promoter function and structure of the growth factor-inducible immediate early gene cyr61. 206 42

Two platelet-derived growth factor A-chain proteins, termed short and long A chains, are generated as a result of alternative mRNA splicing of exon 6 of the A-chain gene. S1 nuclease mapping and polymerase chain reaction analyses demonstrate that both short and long A-chain transcripts are expressed in a variety of normal tissues. In addition, immunohistochemical localization of long A-chain protein reveals a cellular distribution identical to that observed with platelet-derived growth factor heteroserum.
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PMID:Alternatively spliced platelet-derived growth factor A-chain transcripts are not tumor specific but encode normal cellular proteins. 223 32

The c-myc gene is rapidly induced in quiescent Balb/c-3T3 cells in response to the platelet-derived growth factor (PDGF). In order to study the mechanisms by which growth factors regulate induction of c-myc, we have attempted to identify growth factor-responsive elements in the murine c-myc locus. Various fragments of the c-myc gene linked to a bacterial CAT reporter gene were stably transfected into Balb/c-3T3 cells. A construct which includes the P1 promoter and 424 bp of upstream sequences shows a 3-5 fold induction of CAT RNA expression in response to sis/PDGF. S1 nuclease mapping experiments demonstrate that this mRNA initiates from the myc P1 promoter. Nuclear runoff transcription experiments performed with this myc/CAT construct show that this induction occurs at the transcriptional level. Deletion analysis led to the identification of an 81 bp segment in the first exon between the c-myc P1 and P2 promoters which is necessary to confer growth factor responsiveness in this construct.
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PMID:Identification of a PDGF-responsive element in the murine c-myc gene. 225 Sep 9

Thrombospondin (TSP) is an extracellular matrix glycoprotein whose synthesis and secretion by mesenchymal cells is regulated at the level of gene transcription by platelet-derived growth factor. To examine the transcriptional regulation of the TSP gene at the molecular level, a genomic clone containing the human TSP promoter and flanking sequence was isolated and characterized. A 3.8-kilobase pair (kb) DNA fragment containing the first three exons, the first two introns, and 2.2 kb of 5'-flanking region was sequenced, and the site of transcription initiation was determined by both primer extension and S1 nuclease mapping. Consensus sequences for several potential regulatory elements were found in the 5'-flanking sequence, including a TATA box consensus sequence, TTTAAAA, located 24 base pairs upstream from the transcription start site. A chimeric gene was constructed containing the first intron, the first exon, and 2.0 kb of 5'-flanking sequence of the TSP gene fused to the promoterless gene for chloramphenicol acetyltransferase. When transfected into COS-1 or NIH3T3 cells this gene construct was transcribed, indicating the presence of a functional promoter in the TSP sequence. Transient transfection studies using deletion mutants of this TSP-chloramphenicol acetyltransferase construct were performed to locate cis-acting regulatory sequences. The deletion of flanking sequence 5' to position -234 had little or no effect on transcriptional activity, whereas deletion of 5'-flanking sequence extending further in the 3' direction resulted in the gradual loss of transcriptional activity. The removal of the first intron resulted in a 4-fold decrease in transcript levels, indicating the presence of a cis-acting positive element(s) in the first intron of the human TSP gene. This element(s) was further localized to the region between position +576 and position +727.
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PMID:Characterization of the promoter region of the human thrombospondin gene. DNA sequences within the first intron increase transcription. 254 87

Vimentin is a growth-regulated gene whose mRNA levels increase severalfold after stimulation of quiescent cells. We have isolated and sequenced a genomic fragment of human DNA containing the vimentin 5'-flanking sequence and untranslated region. S1 nuclease analysis was used to determine the transcription initiation site. Deletion mutants of the promoter region were constructed, linked to a chloramphenicol acetyltransferase gene, and analyzed for transient expression by transfection into BALB/c 3T3 cells. These experiments revealed the presence in the human vimentin promoter region of a negative-regulatory element, flanked by positive elements. The most 5' of the positive elements is able to overcome the effects of the negative element. Analysis of these deletion constructs in stable cell lines confirmed the results of the transient assays. Using these stable cell lines, we can also demonstrate that the vimentin promoter region can confer platelet-derived growth factor inducibility to a linked chloramphenicol acetyltransferase gene and that the sequences required for this inducibility reside between positions -241 and +73.
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PMID:Functional analysis and growth factor regulation of the human vimentin promoter. 343 46

The structure of the normal human c-sis/platelet-derived growth factor 2 (SIS/PDGF2) transcript was determined by a combination of cDNA cloning, nuclease S1 mapping, and primer extension. Nucleotide sequence analysis revealed that the 3373-nucleotide SIS/PDGF2 mRNA contained only a 723-base-pair (bp) coding sequence for the PDGF2 precursor polypeptide. The coding sequence was flanked by long 5' (1022 bp) and 3' (1625 bp) untranslated regions. The 5' noncoding region, as well as upstream flanking genomic sequences, contained clusters of specific short repeat sequences. A consensus transcriptional promoter sequence, TATAAA, was identified 24 bp upstream of the mRNA start site and an enhancer-like "TG element" was detected about 180 bp downstream from the site of polyadenylylation. These findings identify putative regulatory elements of the SIS/PDGF2 gene.
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PMID:Structure and sequence of the human c-sis/platelet-derived growth factor 2 (SIS/PDGF2) transcriptional unit. 351 69


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