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)

The DnaA protein is the key DNA initiation protein in Escherichia coli. Using transcriptional and translational fusions, comparative S1 nuclease mapping and immunoblot analysis, the regulation of dnaA in relation to inducible responses to DNA damage was studied. We found that DNA damage caused by mitomycin C (MC) and methyl methanesulfonate (MMS) led to a significant induction of the dnaA gene. These results strongly suggest that in response to DNA damage which inhibits DNA replication, an increased initiation capacity is induced at oriC and that, in addition to the known auto-repression, a new regulatory mechanism may be involved in the control of dnaA gene expression. Furthermore, this mechanism might be indirectly related to the SOS regulon, because lexA and recA mutants, which block the induction of the SOS response, prevent dnaA induction by MMS and MC.
Mol Gen Genet 1991 May
PMID:Expression of the dnaA gene of Escherichia coli is inducible by DNA damage. 190 39

S1 nuclease analysis and sub-family-specific oligonucleotide probes were used to characterize the expression during embryogenesis of the napin storage protein gene family of Brassica napus (oilseed rape). The expression of one sub-class represented by the napin gene gNa peaks and declines earlier than the other members of the family. This sub-class was highly expressed representing ca. 20% of napin mRNA at 26 days after anthesis.
Plant Mol Biol 1991 Nov
PMID:Differential expression of members of the napin storage protein gene family during embryogenesis in Brassica napus. 193 83

Repair under non-growth conditions of DNA double-stranded breaks (DSBs) and S1 nuclease-sensitive sites (SSSs; e.g. DNA damage which is processed by in vitro treatment with S1 nuclease to DSBs) induced by [60Co]-gamma-rays (200 Gy; anoxic conditions) was monitored in a diploid repair-competent strain of Saccharomyces cerevisiae. We used pulsed-field gel electrophoresis (PFGE), which allows the separation of chromosome-sized yeast DNA molecules, to determine the number of DSBs and SSSs in individual chromosome species of yeast. Our results indicate that SSSs which have been regarded as clusters of base damage in opposite DNA strands are repaired efficiently in a repair-proficient diploid strain of yeast. The time course of SSS repair is comparable to the one of DSB repair, indicating similarities in the molecular mechanism. Both types of repair kinetics are different for different chromosome species.
Mol Microbiol 1991 Jul
PMID:The repair of double-strand breaks and S1 nuclease-sensitive sites can be monitored chromosome-specifically in Saccharomyces cerevisiae using pulse-field gel electrophoresis. 194 98

To study the regulation of the human glucocorticoid receptor (hGR), we characterized the promoter region by primer extension, S1 nuclease mapping and by DNA sequencing. We found that the promoter is extremely G + C rich (72% GC content) and contains a "TAATA" and a "CAT" box, eight "GGGCGG", three "CCGCCC" and two "CACCC" motifs and a motif similar to the glucocorticoid responsive element (GRE) which included two interchanged nucleotides "TCTTGT". In contrast to other steroid receptor genes, exon I or GHGR contains the major part of the 5' non-coding sequences of hGR mRNA while exon II contains coding sequences for the first 394 amino acid residues of the A/B region of hGR. The major transcriptional start site was found to be 134 bp upstream of the ATG initiation codon. Transfection of HeLa cells with plasmids containing various deletions of GHGR promoter fused to a promoterless CAT vector suggested the region between -470 and -1030, at the 5' end of the mRNA start site, to contain sequences required for down regulation by hormone.
J Steroid Biochem Mol Biol 1991
PMID:Human glucocorticoid receptor gene promotor-homologous down regulation. 195 37

The purpose of this study was to characterize the complete cDNA sequence encoding the rabbit smooth muscle myosin heavy chain (MHC) and determine the exon/intron organization at the 5' end of the corresponding gene. The full-length cDNA sequence of 6644 base pairs encoding a protein of 1972 amino acids was generated from two cDNA clones: PBRUC1 (approximately 6.3 kilobases), isolated from a rabbit uterus cDNA library, and PBRU-PCR33 (420 base pairs), produced by primer extension and PCR amplification. Compared with the chicken smooth muscle MHC sequence [Yanagisawa, M., Hamada, Y., Katsuragawa, Y., Imamura, M., Mikawa, T. & Masaki, T. (1987) J. Mol. Biol. 198, 143-157] the rabbit MHC shares about 90% amino acid identity in the S1 globular head region but shows a striking sequence divergence at the junction between the 25-kDa and 50-kDa proteolytic fragments of the functionally important S1 head domain. Genomic cloning shows that the rabbit smooth muscle MHC gene is large and has an unusual exon/intron organization at the 5' end. The first eight contiguous exons are located within a region of at least 70 kilobases of genomic DNA. Some introns span several kilobases of DNA and others at the 5' end show a high degree of intron conservation in the Mg(2+)-ATPase domain when compared with more distantly related sarcomeric MHC genes. Primer extension and S1 nuclease mapping analysis demonstrate that transcription initiates from a single site in the rabbit smooth muscle MHC gene.
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PMID:Characterization of a mammalian smooth muscle myosin heavy-chain gene: complete nucleotide and protein coding sequence and analysis of the 5' end of the gene. 196 35

In vitro studies have demonstrated that the estrogen receptor (ER) can bind to the rat PRL estrogen response element (ERE) located 1700 basepairs upstream of the transcriptional start site. However, the mechanism by which the receptor-DNA complex influences the activity of RNA polymerase located in the promoter region is not understood. To begin investigating this process, we developed cell lines derived from GH3 cells that contain steroid-responsive bovine papillomavirus minichromosomes. Within these minichromosomes is a hybrid gene composed of the 5' flanking region of the PRL gene, driving the expression of the Tn5 gene. The episomal PRL DNA sequences responded to 17 beta-estradiol (E2) by increasing the rate of Tn5 gene transcription. Nucleosome mapping experiments using micrococcal nuclease demonstrated that nucleosome-like structures were assembled on the minichromosome in an ordered array separated by 150-200 basepairs of DNA. Novel S1 nuclease as well as DNase-I-hypersensitive sites in the chromatin of the promoter and distal regulatory regions of the episomal PRL gene were detected by indirect end-labeling studies. The nuclease hypersensitive sites in the distal region containing the ERE were modified after treatment of the cells with either E2 or the antiestrogen 4-hydroxytamoxifen. However, only E2 treatment of cells resulted in an increase in the nuclease hypersensitivity of the promoter region and induced gene expression, while antiestrogen treatment had no effect on either parameter. This suggests that complex interactions between factors located at the distal and proximal regulatory regions ultimately determine the transcriptional response of the PRL gene to E2.
Mol Endocrinol 1990 Aug
PMID:An interaction between the 5' flanking distal and proximal regulatory domains of the rat prolactin gene is required for transcriptional activation by estrogens. 196 74

Using a solution hybridization-S1 nuclease protection assay, we quantitatively studied tyrosine hydroxylase mRNA (mRNATH) in catecholaminergic cells of the substantia nigra, hypothalamus, superior cervical ganglion, and adrenal of male rats from early neonatal life to old age. Throughout this time, the lowest level of mRNATH in any tissue was found in the youngest animals, and their development was associated with an increase in the quantity of mRNATH. However, the extent of the increase as well as the pattern of change was dependent on the tissue. The amount of mRNATH in the substantia nigra of 1-day-old pups was 162 +/- 7 attomoles (mean and S.E.M.), increasing to 877 +/- 39 amol at 14 days of age. Then, the amount fell to 480 +/- 25 amol at 6 weeks of age, but changed little between 6 weeks and 23 months of age. In the hypothalamus of 1-day-old pups, the quantity of mRNATH was 24 +/- 3 amol, increasing to 60 +/- 6 amol at 2 weeks and changed little thereafter. mRNATH in the superior cervical ganglion increased gradually until 10 months of age; at which time the amount was 3 times that of neonatal animals. In the adrenal, mRNATH increased continuously throughout the period of observation. The amount of mRNATH in the adrenal of 23-month-old animals was 25 times that in the adrenal of 4-day-old pups. These data suggest that tyrosine hydroxylase gene expression does not diminish in aged rats.
Brain Res Mol Brain Res 1990 Jan
PMID:Quantitative study of tyrosine hydroxylase mRNA in catecholaminergic neurons and adrenals during development and aging. 196 14

Chloroplast DNA (cpDNA) from 36 wild species of the genus Helianthus has been analysed with three restriction endonucleases (Bam HI, Hind III and Sst I). Out of the 71 restriction sites described on the reference cpDNA (sunflower cpDNA), three insertions/deletions and seven site modifications were detected during the survey of the other cpDNAs. Since restriction mapping showed only a very limited fraction of the DNA variability, we chose to adapt the S1 nuclease mapping technique to detect fine variations between chloroplast genomes. For this purpose, DNA-DNA heteroduplexes obtained between sunflower and wild-species DNAs were digested by S1 nuclease and the resulting mismatches were detected by classical endonuclease restriction and hybridization methods. The S1 nuclease mapping results were confirmed by sequencing one S1 nuclease-sensitive region detected between cultivated sunflower and two perennial wild-type species. As a result of these analyses, it appeared that the combination of restriction mapping and S1 nuclease mapping might be helpful to differentiate taxonomically close cytoplasms.
Plant Mol Biol 1990 Aug
PMID:Chloroplast DNA variability in the genus Helianthus: restriction analysis and S1 nuclease mapping of DNA-DNA heteroduplexes. 198 99

We have cloned and sequenced a mouse genomic transforming growth factor beta 1 (TGF-beta 1) DNA fragment that includes the 5' untranslated and regulatory regions of the gene. High-sequence homology with the human TGF-beta 1 gene (66% nucleotide identity in 2.7 kb of DNA upstream of the translational start site) suggested evolutionary conservation of transcriptional regulation for TGF-beta 1. The absence of TATA or CAAT box sequences but the presence of several Sp1-binding and AP-2-like sequences in the promoter region was noted, as previously reported for the human gene. Two transcriptional initiation sites separated by 290 bp were identified by S1 nuclease analysis; these corresponded to transcripts with 866 and 576 nucleotides of 5' untranslated leader sequence. S1 analysis of different mouse tissues indicated that the two transcripts were present in the same ratio even though the total level of TGF-beta 1 mRNA transcripts varied between tissues. Promoter activity adjacent to both transcriptional start sites was demonstrated by using chloramphenicol acetyltransferase fusion genes assayed in mouse AKR-2B fibroblast cells. Transcriptional activation of the promoter by the Ha-ras oncogene was also demonstrated. The minimal promoter constructs (113 and 104 bp 5' of the first and second transcriptional start sites, respectively) were sufficient for induction by Ha-ras. These studies characterize the 5' structure and basal promoter activity of the mouse TGF-beta 1 gene as well as the transcriptional activation of TGF-beta 1 by the Ha-ras oncogene.
Mol Cell Biol 1991 Jan
PMID:Characterization of the mouse transforming growth factor-beta 1 promoter and activation by the Ha-ras oncogene. 198 55

In retroviral proviruses, the poly(A) site is present in both long terminal repeats (LTRs) but used only in the 3' position. One mechanism to account for this selective poly(A) site usage is that LTR U3 sequences, transcribed only from the 3' poly(A) site, are required in the RNA for efficient processing. To test this possibility, mutations were made in the human immunodeficiency virus type 1 (HIV-1) U3 region and the mutated LTRs were inserted into simple and complex transcription units. HIV-1 poly(A) site usage was then quantitated by S1 nuclease analysis following transfection of each construct into human 293 cells. The results showed that U3 sequences confined to the transcription control region were required for efficient usage of the HIV-1 poly(A) site, even when it was placed 1.5 kb from the promoter. Although the roles of U3 in processing and transcription activation were separable, optimal 3' end formation was partly dependent on HIV-1 enhancer and SP1 binding site sequences.
Mol Cell Biol 1991 Mar
PMID:Involvement of long terminal repeat U3 sequences overlapping the transcription control region in human immunodeficiency virus type 1 mRNA 3' end formation. 199 11


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