Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: DrugBank:BIOD00001 (DNase I)
 8,324 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The endonuclease DNase II preferentially attacks a limited and tissue-specific portion of chromosomal DNA. This material may be separated from the bulk of chromatin DNA by virtue of its solubility in 2 mM MgCl2. The Mg2+ soluble fraction forms a specific subset of DNA sequences and is enriched four to sevenfold in sequences coding for cytoplasmic poly(A)-containing RNA and globin messenger RNA (in globin-producing cells). The bulk (70--90%) of rapidly labelled RNA is found associated with the Mg2+-soluble fraction. Transcriptionally active, Mc2+-soluble chromatin is organized into repeating subunits of DNA (200 +/- 5 base pairs) and histone. Mc2+-soluble active subunits differ from the subunits or nucleosomes of non-transcribed regions in many respects: namely, chemical composition (non-histone protein and RNA), sedimentation properties, differential sensitivity to DNase I and the single-strand-specific nuclease S1, and optical melting behaviour. These results suggest that chromatin subunits adopt a new configuration during the process of transcription.
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PMID:Organization of transcribed regions of chromatin. 2 80

Viable mutants of simian virus 40 (SV40), with deletions ranging in size from 15 to 200 base pairs, have been obtained by infecting CV-1P cells with circularly permuted linear SV40 DNA. The linear DNA was produced by cleavage of closed circular DNA with DNase I in the presence of Mn2+, followed, in some cases, by mild digestion with lambda 5'-exonuclease. The SV40 map location and the size of each deletion were determined by using the S1 nuclease mapping procedure (Shenk et al., 1975) and the change in size of fragments produced by Hind II + III endonuclease cleavage. Deletions in at least three regions of the SV40 chromosome have slight or no effect on the rate or yield of viral multiplication and on vira-induced cellular transformation. These regions are located at the following coordinates on the SV40 physical map: 0.17 to 0.18; 0.54 to 0.59; and 0.68 to 0.74.
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PMID:Construction and analysis of viable deletion mutants of simian virus 40. 17 2

The attachment of replicating DNA to a rapidly sedimenting nuclear structure was investigated by digestion with various nucleases. When DNA was gradually removed by DNase I, pulse label incorporated during either 1 min or during 1 hour in the presence of arabinosylcytosine, remained preferentially attached to the nuclear structure. Single strand specific digestion by nuclease S1 or staphylococcal nuclease at low concentrations caused a release of about 30% of the pulse label, without significantly affecting the attachment of randomly labelled DNA. The released material had a low sedimentation coefficient and contained most of the Okasaki fragments. The remaining pulse label was less accessible to further digestion by double strand specific nuclease activity than the bulk DNA. The results suggest that an attachment of the replication fork to the nuclear structure occurs at sites behind but close to the branch point.
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PMID:Analysis of the attachment of replicating DNA to a nuclear matrix in mammalian interphase nuclei. 42 90

A deoxyribonuclease inhibitor has been purified from KB cells by chromatography on single-stranded DNA-cellulose. Polyacrylamide gel electrophoresis showed the purified preparation to contain two major polypeptides in sodium dodecyl sulfate, with molecular weights of 72,000 and 65,000, but only one major band (with a molecular weight of approximately 140,000) after electrophoresis under nondenaturing conditions. The protein inhibits the hydrolysis of single-stranded DNA by KB DNase, DNase I, DNase II, and nuclease S1, but has no effect on the hydrolysis of double-stranded DNA by these enzymes. The inhibitor causes a reduction in the rate of hydrolysis of DNA by the deoxyribonuclease, probably by reducing the effective concentration of substrate.
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PMID:A deoxyribonucleic acid binding protein from KB cells which inhibits deoxyribonuclease activity on single-stranded DNA. 42 57

Non-membranous HeLa cell nuclear ghosts, representing non-membranous nuclear envelope or 'skeletal' components, have been examined in whole-mount fashion by transmission electron microscopy. Major components of the ghosts include annuli with inner and outer diameters of 43 and 90 nm, respectively, which are consistent in dimensions with nuclear pore complexes. Also present are rod-like images (260 nm in length and 50 nm in width or diameter) representing either previously unobserved nuclear structures, or condensations of repeating functional units not otherwise observable. The annular and rod-like images were also observed when various steps in the ghost isolation procedure, such as the use of detergents, 0.5 M MgCl2 and polylysine attachment of the ghosts to electron-microscope grids, were circumvented. The annular and rod-like images are connected into linear and polygonal arrays by strands (15-30 nm in width) that are sensitive to DNase I and DNase II but resistant to nuclease S1. Thus, although the non-membranous ghosts from HeLa cells are composed primarily of protein, enzymic dissection indicates that their gross integrity is markedly dependent on double-stranded DNA. Nuclear ghosts prepared from a wide range of species including mammals, birds and plants, exhibited essentially the same components and organization.
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PMID:The ultrastructure of non-membranous nuclear ghosts. 70 96

Digestion of fixed metaphase chromosomes by endonucleases (micrococcal nuclease and DNase II) under optimal digestion conditions followed by Giemsa staining produces sharp banding patterns identical to G-bands. In 3H-thymidine labeled, synchronized metaphase cells of the chinese hamster (CHO line), the band induction is accompanied by the removal of DNA. The single strand specific nuclease S1 and DNase I do not produce such banding patterns.
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PMID:Responses of mammalian metaphase chromosomes to endonuclease digestion. 74 3

The transcriptional start sites of the endogenous human thrombomodulin (TM) gene and transiently expressed TM promoter/CAT gene constructs were defined by nuclease S1 mapping which showed two closely spaced sites at +1 and +6, respectively. Transient expression and in vitro transcription assays of 5' and internal deletion mutants of the TM promoter/CAT gene constructs reveal that the region from -72 to -29 exhibits a positive acting domain which is essential for transcriptional activity, whereas the region from -373 to -225 possesses two positive acting subdomains, -343 to -277 and -245 to -225, which together augment transcriptional activity by about 40%. Electrophoretic mobility shift assays with a duplex oligonucleotide corresponding to -72 to -29 and DNase I footprinting experiments show two specific interaction products which individually or cooperatively protect the DNA sequence from about -60 to -30. These components are essential for TM gene transcription since affinity fractionation of nuclear extracts with a duplex oligonucleotide corresponding to -72 to -29 depletes the above interaction products and specifically inhibits in vitro transcription activity of the promoter, whereas addition of the eluted components specifically restores in vitro transcription activity of the promoter. Electrophoretic mobility shift assays with duplex oligonucleotides corresponding to -294 to -215, as well as -373 to -295 and DNase I footprinting experiments show two specific interaction products which individually bind to the two subdomains but not -72 to -29 and protect the coding and noncoding strands from -245 to -225, and the noncoding strand from -337 to -314, respectively. Transient expression studies reveal that the TM promoter construct starting at -51 and including the TATA box is responsive to TNF only in cell lines exhibiting sensitivity of the endogenous receptor gene to cytokine, whereas other promoter constructs possessing a TATA box sequence are insensitive to TNF in all cell types. Based upon the above data, the regulatory events involved in TNF-dependent transcriptional regulation of the TM gene can be defined with the experimental tools and conceptual framework developed by the present investigation.
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PMID:Transcriptional regulation of the thrombomodulin gene. 133 Oct 78

To investigate the regulatory processes involved in the expression of the D2 dopamine receptor gene, a rat genomic clone was isolated using a 21-mer oligonucleotide probe made of exon 1 sequences. A 1.3-kb region including all of exon 1, its 5'-flanking region, and part of intron 1 was sequenced. S1 nuclease analysis indicated three consecutive nucleotides as the main transcription start sites; several weaker sites were also noted between 321 and 363 nucleotides upstream from the 3' end of exon 1. The promoter region lacks TATA and CAAT boxes and is rich in G+C content with several putative Sp1 binding sites. Transient expression assays using chimeric constructs of D2 promoter deletion mutants-chloramphenicol acetyl-transferase gene in the neuroblastoma cell line NB41A3 which expresses D2 binding sites indicated strong transcription enhancing activity between nucleotides -75 and -30 and silencing activity between nucleotides -217 and -76. DNase I footprinting studies using nuclear extract from NB41A3 suggested Sp1 binding to its consensus sequence at nucleotide -48 but inhibition of Sp1 binding at nucleotide -86 by the extract. The D2 promoter could not induce transcription of the heterologous CAT gene in C6 glioma, embryonal NIH 3T3, or hepatic Hep G2 cells. It is concluded that the rat D2 gene shares with the human D1A dopamine receptor gene several features typical of "housekeeping" genes but they are both tissue-specific, regulated genes. Unlike the D1A gene, however, the D2 gene has a strong preference for transcription initiation to three consecutive nucleotides.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Analysis of the promoter region of the rat D2 dopamine receptor gene. 139 Jun 23

The DNA sequence of the Salmonella typhimurium metA control region is presented. S1 nuclease mapping was used to determine the transcription initiation site. By measuring beta-galactosidase levels in Escherichia coli strains lysogenized with lambda phage carrying a metA-lacZ gene fusion, the MetR protein was shown to activate the metA gene. Homocysteine, an intermediate in methionine biosynthesis, plays a negative role in the MetR-mediated activation mechanism. Gel mobility shift assays and DNase I protection experiments showed that the MetR protein binds to a DNA fragment carrying the metA control region and protects a 26-bp region beginning 9 bp upstream of the -35 promoter sequence.
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PMID:Regulation of the Salmonella typhimurium metA gene by the metR protein and homocysteine. 172 33

We cloned the cryptic phn operon of a K-12 strain, phn(EcoK), and analyzed the nucleotide sequence of the phn region (11,672 bp). An mRNA start site upstream of the phnC gene was identified by S1 nuclease mapping. The pho regulon activator PhoB protects a pho box region near the mRNA start in DNase I footprinting and methylation protection experiments. The sequence of the cryptic phn(EcoK) operon was very similar to that of the functional phn operon of an Escherichia coli B strain, phn(EcoB) (C.-M. Chen, Q.-Z. Ye, Z. Zhu, B. L. Wanner, and C. T. Walsh, J. Biol. Chem. 265:4461-4471, 1990). The phnE(EcoK) gene has an 8-bp insertion, absent from the phnE(EcoB) gene, which causes a frameshift mutation. The spontaneous activation of the cryptic phn(EcoK) operon is accompanied by loss of this additional 8-bp insertion. Studies of the structure, regulation, and function of the phn region suggest that the phosphate starvation-inducible phn operon consists of 14 cistrons from phnC to phnP.
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PMID:Molecular analysis of the cryptic and functional phn operons for phosphonate use in Escherichia coli K-12. 184 May 80


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