Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.22.1 (DNase II)
 429 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The following procedures have been used to prepare fifteen modified dinucleoside monophosphates: (a) bisulfite-catalyzed transamination with aniline to give an N4-phenylcytidine (CPh), (b) bisulfite-catalyzed transamination with beta-naphthylamine to give an N4-beta-naphthylcytidine (CbetaN), (c) alkylation with 7-bromomethylbenz[a] anthracene to afford a 7(benz[a]anthryl-7-methyl)guanosine (GMBA), and (d) reaction with N-acetoxy-2-acetylaminofluorene to give an 8-(N-2-fluorenylacetamido)guanosine (GAAF). The compounds prepared were A-CPh, CPh-A, CPh-G, U-CPh, CPh-U, A-CbetaN, CbetaN-A, G-CbetaN, CbetaN-G, U-CbetaN, CbetaN-U, GMBA-U, U-GMBA, GAAF-U, and U-GAAF. All of the modified compounds were hydrolyzed to the expected monomers with venom and spleen exonucleases. Hydrolysis by micrococcal nuclease was inhibited in the following cases: A-CPh, A-CbetaN, U-GMBA, and U-GAAF. The first three reactions above were applied to denatured calf thymus DNA to prepare modified DNA samples containing from 0.3 to 2.0% bound aromatic residues. The modified nucleic acids were completely hydrolyzed to nucleosides by the combination of venom exonuclease, deoxyribonuclease I and alkaline phosphatase. The same results were obtained with a combination of spleen exonuclease, deoxyribonuclease II, and alkaline phosphatase. Hydrolysis of the modified nucleic acids by micrococcal nuclease and alkaline phosphatase afforded primarily nucleosides, with some dinucleoside monophosphates. The amount of the latter did not exceed that found in the hydrolysis of control DNA, however. Other workers have observed inhibition of enzymatic hydrolysis of nucleic acids modified by aromatic carcinogens. We postulated that their results may have been caused by cross-links, which were avoided in our studies.
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PMID:Preparation and enzymatic hydrolysis of dinucleoside monophosphates and DNA modified with aromatic residues. 55 43

Liver nuclei were prepared through the first cell cycle in partially hepatectomized young rats showing 30% parenchymal cell synchrony. To determine if nucleosome structure altered during this period, liver nuclei from sham-operated rats were compared with nuclei isolated at various times after partial hepatectomy. These nuclei were exposed to deoxyribonuclease I (EC 3.1.4.5), deoxyribonuclease II (EC 3.1.4.6) or micrococcal nuclease (EC 3.1.4.7) and the nucleosome-associated DNA length was ascertained. In no case was a difference in the DNA lengths associated with nucleosome structure observed. Differences were observed with regard to the histones and their relative association with nuclear material. When nuclei from normal rat livers were incubated in hypo-osmolar medium 9% of histone 1 and 4% of the other histones were released. These released histones, unlike those remaining bound to the nuclei, showed high [3H]adenosine and [3H]acetate uptakes in vivo. [32P]P1 uptake was also much greater into released than bound histones 1 and 3, but was not different for histone2A. At 3.5-4.5 h after partial hepatectomy, the release of histone 1 was trebled and that of histone 4 doubled. By 13.5 h, when phosphorylation of the bound forms of histones 2A and especially 1 was increased, no further changes in histone release in hypo-osmolar medium were found. The released histones from partially hepatectomized livers had indistinguishable [3H]adenosine uptakes from controls. The roles are discussed of phosphorylation and ADP-ribosylation in labilizing histone binding.
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PMID:Chromatin structure through the cell cycle. Studies with regeneration rat liver. 70

The arrangement of the protein component on the DNA of the chromatin complex was studied by comparing the rate of release of oligonucleotides and of protein after addition of deoxyribonuclease I and deoxyribonuclease II to rat thymus chromatin. Also the action of deoxyribonuclease I on normal chromatin and on chromatin depleted of non-histone protein was compared, to elucidate the role of the latter protein in chromatin structure. As a preliminary to the above, the rate of action of deoxyribonuclease I on DNA and on chromatin at the same DNA concentration, and the dependence of the action of this enzyme on the Mg(2+) concentration, were studied. It was found that: (1) little if any DNA in chromatin is present in extensive, truly ;free' zones, i.e. completely uncovered by protein; (2) at relatively low concentrations of added Mg(2+), deoxyribonuclease I degrades chromatin more rapidly than DNA; (3) the non-histone protein is not attached directly to the DNA in chromatin.
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PMID:The arrangement of proteins on the deoxyribonucleic acid in chromatin. 433 34

Differentiation of cartilage from precartilage mesenchyme in the chick embryo is accompanied by the loss of two abundant nonhistone proteins (Mr 35 500 and 125 000) termed PCP 35.5 and PCP 125. Here we examine the distribution of these and other developmentally regulated nonhistones in nuclease-sensitive regions of precartilage and cartilage chromatin. In particular, we show that PCP 35.5 is a tight DNA-binding protein that is localized near deoxyribonuclease I (DNase I) sensitive regions of precartilage chromatin. Localization of nonhistones was demonstrated by excising domains of precartilage chromatin with DNase II which are simultaneously highly enriched in PCP 35.5, in PCP 125, and DNase I sensitive DNA sequences. These domains comprise at least 25% of the cell's DNase I sensitive sequences, as well as small DNase I resistant regions with which the two nonhistones are associated. These findings suggest that PCP 35.5 (and possibly PCP 125) may play a developmentally regulated role nearby DNase I sensitive domains of the cartilage progenitor cell chromatin.
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PMID:Developmentally regulated nonhistone proteins: evidence for deoxyribonucleic acid binding role and localization near deoxyribonuclease I sensitive domains of precartilage cell chromatin. 628 99

Research into the use of new genetic markers is difficult and costly, but it is necessary for more accurate criminal individualization and paternity testing as well as for analysis of genetic diseases. Recently, we discovered that human ribonuclease (RNase), deoxyribonuclease I (DNase I) and deoxyribonuclease II (DNase II) are characteristic markers showing genetic polymorphism and useful for forensic investigation. DNase I is particularly well suited to practical use, since it shows a well-balanced gene frequency, a high concentration in several body fluids (blood, sweat, urine, breast milk and semen) and tissues (pancreas, liver and kidney), stability against severe conditions (exposure of test samples to high temperature, high humidity and long-term storage), and easy and accurate detectability.
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PMID:[Discovery of genetic polymorphism of human nucleases]. 895 29

This review describes several types of genetic polymorphism, which have recently been identified in human urine in our laboratory, and have also been found in other human body fluids such as blood, saliva and semen. These include uropepsinogen, ribonuclease, deoxyribonuclease I (DNase I), deoxyribonuclease II (DNase II), 43-kDa glycoprotein, alpha-L-fucosidase, glutamate pyruvate transaminase, alpha-2-HS-glycoprotein, transferrin and vitamin D-binding protein. Several substances can be detected more easily in urine than in plasma. The concentrations of uropepsinogen, DNase I and DNase II in blood plasma are too low for analysis, whereas those in urine are high enough for easy typing. In practice, DNase I-polymorphism is one of the most useful genetic markers for practical purposes, because of its higher content in various body fluids including urine, a well-balanced gene frequency, and its easy and accurate detectability. Furthermore, several genetic markers previously identified in blood and/or other forensic samples can be phenotyped reproducibly and easily from the corresponding urine samples. Thus, urine, in addition to the convenience and non-invasive nature of its collection, is by no means inferior to blood as a sample source for typing in the field of forensic science. Biochemical and serological typing of genetic polymorphisms present in human urine could offer useful information to practising forensic biologists for forensic individualization of urine samples.
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PMID:Genetic polymorphisms detectable in human urine: their application to forensic individualization. 954 53

Vitamin C (VC) and vitamin K(3) (VK(3)) administered in a VC:VK(3) ratio of 100:1 exhibit synergistic antitumor activity and preferentially kill tumor cells by autoschizis, a novel type of necrosis characterized by exaggerated membrane damage and progressive loss of organelle-free cytoplasm through a series of self-excisions. During this process, the nucleus becomes smaller, cell size decreases one-half to one-third of its original size, and most organelles surround an intact nucleus in a narrow rim of cytoplasm. While the mitochondria are condensed, tumor cell death does not result from ATP depletion. However, vitamin treatment induces a G(1)/S block, diminishes DNA synthesis, increases H(2)O(2) production, and decreases cellular thiol levels. These effects can be prevented by the addition of catalase to scavenge the H(2)O(2). There is a concurrent 8- to 10-fold increase in intracellular Ca(2+) levels. Electrophoretic analysis of DNA reveals degradation due to the caspase-3-independent reactivation of deoxyribonuclease I and II (DNase I, DNase II). Redox cycling of the vitamins is believed to increase oxidative stress until it surpasses the reducing ability of cellular thiols and induces Ca(2+) release, which triggers activation of Ca(2+)-dependent DNase and leads to degradation of DNA. Recent experiments indicate that oral VC:VK(3) increases the life-span of tumor-bearing nude mice and significantly reduces the growth rate of solid tumors without any significant toxicity by reactivating DNase I and II and inducing autoschizis. This report discusses the mechanisms of action employed by these vitamins to induce tumor-specific death by autoschizis.
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PMID:Autoschizis: a novel cell death. 1203 62