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)

Antiviral activity has been found in conceptus and placental tissues in numerous species, including mice, pigs, sheep, cattle and humans. In sheep and cattle, the antiviral activity is due to an interferon alpha (IFN-alpha), but in other species the nature of the protein(s) responsible for placental activity is unknown. The objectives of this study were to determine if the constitutive antiviral activity associated with the mouse conceptus is produced as early as the peri-implantation period, and to determine if the activity is due to an IFN-alpha or -beta. Conceptus and placental tissue explants released antiviral activity from Day 4 through at least Day 16 of gestation as measured in an agar overlay bioassay employing CHO cells challenged with vesicular stomatitis virus. This activity was neutralized by antiserum against MuIFN-alpha/beta. The same antiserum failed, however, to immunoprecipitate radiolabeled proteins from medium collected from Day 4 blastocysts cultured in the presence of L-[35S]-methionine. S1 nuclease analysis of placental RNA and screening of ectoplacental cone and extraembryonic ectoderm cDNA libraries with MuIFN-alpha and -beta probes failed to detect IFN related mRNAs, even under relatively non-stringent conditions of hybridization. Thus, while antiviral activity is produced by peri-implantation conceptuses in several diverse mammalian species, it does not appear to be due to a conserved type of IFN in all these species.
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PMID:Characterization of the antiviral activity constitutively produced by murine conceptuses: absence of placental mRNAs for interferon alpha and beta. 237 95

Androgens mediate their effects through an intracellular receptor that is a member of the steroid/thyroid hormone family of receptors. The expression of this protein is tightly regulated in different tissues and among cell types within a single tissue. To define the mechanisms controlling the expression of the androgen receptor, we have isolated and characterized the promoter of the androgen receptor gene in the human prostate cell line LNCaP. The major site of transcription initiation is approximately 1.1 kilobases upstream of the initiator methionine of the androgen receptor protein. The promoter region lacks typical "TATA" and "CAAT" sequence motifs but lies in a GC-rich region and contains a putative Sp1 binding site characteristic of a "housekeeping" promoter and a 44-base segment composed of alternating adenosine and guanosine residues. S1 nuclease protection analyses indicate that the same promoter is employed both in human tissues (prostate, testes), in genital skin fibroblasts, in T47D and MCF-7 breast cancer cells, and in LNCaP prostate cancer cells.
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PMID:Expression of the human androgen receptor gene utilizes a common promoter in diverse human tissues and cell lines. 238 Jan 87

DNA complementary to the bovine retinal mRNA coding for the beta-subunit of transducin has been cloned by screening a cDNA library with oligodeoxyribonucleotide probes. Nucleotide sequence analysis of the cloned cDNA has revealed that this polypeptide consists of 340 amino acid residues (including the initiating methionine). Furthermore, cDNA hybridizable with a transducin beta-subunit cDNA probe has been cloned from a library derived from bovine brain poly(A)+ RNA. Comparison of the cloned cDNAs, in conjunction with blot hybridization analysis and S1 nuclease mapping of poly(A)+ RNA from bovine retina, brain and liver, suggests that the mRNAs coding for the beta-subunits of transducin and other guanine nucleotide binding proteins have the same protein-coding sequence but partly different 5'-noncoding sequences.
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PMID:Primary structure of the beta-subunit of bovine transducin deduced from the cDNA sequence. 241 28

The nucleotide sequence of afsB from Streptomyces coelicolor A3(2), a pleiotropic gene which positively controls the biosynthesis of A-factor and the pigmented antibiotics actinorhodin and undecylprodigiosin in S. coelicolor A3(2) and "Streptomyces lividans," was determined. The determinant of the afsB gene, which includes the putative AfsB protein consisting of 243 amino acids, was mapped functionally by tests for A-factor and pigment production in "S. lividans" and S. coelicolor A3(2) after introduction of recombinant plasmids containing various restriction endonuclease fragments on the vector plasmids pIJ41 and pIJ702. The putative AfsB protein contains two regions separated by 167 residues which resemble conserved domains of known DNA-binding proteins. High-resolution nuclease S1 protection mapping revealed that the afsB mRNA, approximately 1,300 base pairs (bp) long, which was determined by Northern blot hybridization, had its start point 340 bp upstream of the putative methionine start codon. The Northern hybridization experiment also suggested that the afsB gene was constitutively transcribed throughout growth. Also shown by the Northern hybridization was the presence of an unidentified gene with an extraordinary amount of 880-bp mRNA located downstream from afsB. Dot hybridization with the brown pigment production genes, possibly involved in polyketide biosynthesis, as the probe suggested that the afsB gene did not stimulate transcription of the pigment production genes. In Southern blot DNA-DNA hybridization analysis with the afsB sequence as the probe, sequences exhibiting various degrees of homology were found in several Streptomyces spp. A DNA sequence showing strong homology to the afsB in Streptomyces griseus FT-1, a high streptomycin producer, behaved like an extrachromosomal element, homologous to the afsA gene, a structural gene for A-factor biosynthesis.
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PMID:Nucleotide sequence of afsB, a pleiotropic gene involved in secondary metabolism in Streptomyces coelicolor A3(2) and "Streptomyces lividans". 242 9

The complete nucleotide sequences of the 1.2-kilobase HindIII fragments which contain the pilin genes of two independently isolated strains of Pseudomonas aeruginosa (PAK and PA103) have been determined and compared to that of strain PA01 (Sastry, P. A., Finlay, B. B., Pasloske, B. L., Paranchych, W., Pearlstone, J. R., and Smollier, L. B. (1985) J. Bacteriol. 164, 571-577). The fragments share extensive regions of homology, including the 5'- and 3'-flanking sequences as well as the 5' end of the pilin gene. The most highly diverged segments of the pilin genes are those which encode the variable carboxyl-terminal region of the pilin polypeptides. The pilin polypeptides each contain a 6-amino acid amino-terminal leader peptide (Met-Lys-Ala-Gln-Lys-Gly) and are nearly identical in the following 60 amino acids. The carboxyl-terminal portion of the pilin polypeptides contain extensive regions of divergence in their amino acid sequences, although hydropathicity analysis of the pilin polypeptides indicated that they are structurally similar. The transcriptional initiation site of the PAK pilin gene has been determined by S1 nuclease mapping. The promoter region at -10 and -35 base pairs from the transcriptional initiation site shows no significant homology to the consensus Escherichia coli promoter, but the -12 and -24 regions show a high degree of homology to promoters which require the ntrA gene product for transcription. Several other Pseudomonas promoters and the promoters of the homologous pilin genes from other bacterial species also share homology to this sequence.
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PMID:Nucleotide sequence and transcriptional initiation site of two Pseudomonas aeruginosa pilin genes. 243 Sep 61

We have examined transcriptional start sites responsible for expression of the transposase and transposition inhibitor proteins encoded by IS50R, and determined the likely translational start site of transposase. Amino-terminal analysis of a transposase-beta-galactosidase fusion protein gave the sequence Met-Ile-Thr-Ser-Ala, which corresponds to the predicted amino acid sequence starting at position 93 of IS50. S1 nuclease mapping of IS50 RNA produced in vivo indicated that three transcripts, T1, T2 and T3, start near this position. Only T1 starts upstream from the transposase amino terminus. T2 corresponds to an in-vitro transcript described previously. Analysis of the transcripts and proteins produced from deletion derivatives of an IS50-lacZ construct suggested that the three transcripts initiate at independent but overlapping promoters clustered near the end of IS50. This analysis confirmed that only T1 can encode transposase, and that T2 is largely responsible for expression of the inhibitor protein. The coding capacity of T3 was not determined. Finally, transcripts that originate outside of IS50 are prevented from expressing transposase because of a secondary structure that is present in these transcripts only.
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PMID:Transcriptional and translational initiation sites of IS50. Control of transposase and inhibitor expression. 243 19

The gene for the mouse myelin proteolipid protein has been isolated and the seven exons have been sequenced. Since the sequence of a rat proteolipid protein cDNA and partial sequence of the human proteolipid protein gene have been determined, it was possible to demonstrate a very high degree of conservation for the proteolipid protein gene exons among species. While there are some nucleotide changes, the protein coding region of the mouse gene encodes protein that is totally conserved relative to both rat and human proteolipid proteins. The regulatory and noncoding regions of the proteolipid protein gene are also highly conserved. The upstream regulatory and 5'-noncoding region of the gene is 92% homologous to the comparable region of the human proteolipid protein gene, and the 3'-noncoding region of the mouse gene is approximately 90% homologous to a rat proteolipid protein cDNA through 2,200 nucleotides of 3'-noncoding DNA. S1 nuclease protection experiments indicated that the major 5'-end for proteolipid protein mRNAs from mouse, rat, human, or baboon is approximately 147-160 nucleotides upstream from the initial methionine codon of the protein coding region. Other S1 nuclease protection experiments indicated the possible existence of an alternative splice site within exon 3, which may produce mRNA for DM20. This mRNA is approximately 100 nucleotides shorter than that for the proteolipid protein, and it is missing the latter half of exon 3, that is, amino acids 116-150 of the proteolipid protein sequence.
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PMID:Structure and expression of the mouse myelin proteolipid protein gene. 244 35

In heterocysts of the filamentous cyanobacterium Anabaena 7120 a specific [2Fe-2S] ferredoxin is synthesized, serving as immediate electron donor to nitrogenase. The structural gene for this heterocyst ferredoxin, fdxH, was isolated from a recombinant lambda library, using an oligonucleotide probe derived from a unique segment of the N-terminal amino acid sequence of the purified protein. The sequence of the entire fdxH coding region was determined including 3' and 5' flanking sequences. Assuming proteolytic cleavage of the first methionine residue, the molecular weight of Anabaena 7120 heterocyst ferredoxin is 10,806. Compared with the ferredoxin from vegetative cells, 47 out of 98 amino acid residues are different, including conversions within a highly conserved region responsible for binding of the iron-sulfur cluster. Northern hybridization with a 0.64 kb EcoRI DNA fragment containing the entire fdxH gene indicated two major transcripts of 0.59 and 1.85 kb, which are expressed at a late stage of heterocyst differentiation. By S1 nuclease digestion and primer extension a possible start site of transcription was mapped, 132 bp upstream of fdxH; however, neither a typical Escherichia coli nor nif-type promoter sequence was apparent. Southern hybridization detected only one copy of the fdxH gene in the Anabaena 7120 genome. FdxH is located approximately 7 kb downstream from the nifHDK gene cluster.
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PMID:Molecular cloning and nucleotide sequence analysis of the gene coding for heterocyst ferredoxin from the cyanobacterium Anabaena sp. strain PCC 7120. 246 84

We have measured mRNA levels for thrombomodulin, an endothelial membrane cofactor for the activation of protein C by thrombin, in a mouse hemangioma cell line. Cycloheximide, an inhibitor of protein synthesis, increased levels of thrombomodulin mRNA, as measured in an S1 nuclease protection assay, to 2.5-4.0 times control levels. Thrombomodulin transcription in response to cycloheximide treatment, as determined by nuclear run-on analysis, was 3.9 +/- 1.3 (mean +/- SD) times that found in untreated cells. Thrombin also increased thrombomodulin mRNA levels to 151 +/- 21% (mean +/- SD) of control levels after 2 hr. Transcription increased in response to thrombin by 2.1- to 7.3-fold. The combination of thrombin and cycloheximide had no additive effect on thrombomodulin mRNA levels. Thrombin treatment of hemangioma cells also caused an increase in thrombomodulin protein synthesis to 142 +/- 17% (mean +/- SD) of control levels as determined by immunoprecipitation of [32S]methionine-labeled thrombomodulin. We conclude that thrombomodulin expression is determined in part by the rate of transcription and that thrombomodulin mRNA levels in hemangioma cells are increased by treatment with cycloheximide or thrombin. The increased transcription in response to cycloheximide suggests the existence of a labile protein repressor of thrombomodulin transcription.
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PMID:Transcription of thrombomodulin mRNA in mouse hemangioma cells is increased by cycloheximide and thrombin. 255 Sep 31

Haploid cells of mating type A of the basidiomycetous yeast Rhodosporidium toruloides secrete a mating pheromone, rhodotorucine A, which is an undecapeptide containing S-farnesyl cysteine at its carboxy terminus. To analyze the processing and secretion pathway of rhodotorucine A, we isolated both genomic and complementary DNAs encoding the peptide moiety. We identified three distinct genes, RHA1, RHA2, and RHA3, encoding four, five, and three copies of the pheromone peptide, respectively. Complementary DNA clones were classified into two types. One type was homologous to RHA1, and the other type was homologous to RHA2. Transcription start sites were identified by primer extension and S1 nuclease protection, from which the site of the initiator methionine was verified. A primary precursor of rhodotorucine A was detected as a 7-kilodalton protein by immunoprecipitation of in vitro translation products. On the basis of these results, we propose similar three-precursor structures of rhodotorucine A, each containing the amino-terminal peptide sequence Met-Val-Ala. The precursors contain three, four, or five tandem repeats of the pheromone peptide, each separated by a spacer peptide, Thr-Val-Ser(Ala)-Lys, and each precursor has the carboxy-terminal sequence Thr-Val-Ala. This structure suggests that primary precursors of rhodotorucine A do not contain canonical signal sequences.
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PMID:Multiple genes coding for precursors of rhodotorucine A, a farnesyl peptide mating pheromone of the basidiomycetous yeast Rhodosporidium toruloides. 257 24


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