Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.1.25.1 (deoxyribonuclease)
1,471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Treatment of neuroblastoma cells with dibutyryl-adenosine 3':5'-monophosphate or adenine induced axon formation and a three-fold increase in the polyadenylate, poly(A), content of the polysomal mRNA. The extracted poly(A) contained 90% adenylic acid and showed a mobility of 6--7 S in dodecylsulfate-polyacrylamide gel electrophoresis. Treatment with dibutyryl-adenosine 3':5'-monophosphate or adenine, also induced a 4--6 fold increase in a nuclear enzymic activity that incorporated [3H]ATP to an acid-insoluble polymer in a cell-free system. This polymer, like poly(A) extracted from the polysomal mRNA, was bound at high salt concentration to nitrocellulose filters. [3H]ATP incorporation was Mg2+-dependent, sensitive to ribonuclease and EDTA and resistant to deoxyribonuclease and actinomycin D. There was no incorporation of [3H]UTP or [3H]dTTP and addition of TUP, CTP and GTP did not increase the incorporation of [3H]ATP. 5-Bromodeoxyuridine induced axon formation of neuroblastoma cells and poly(A) polymerase activity, without increasing the poly(A) content in the polysomal mRNA. The results indicate that induction of axon formation of neuroblastoma cells is associated with an increase in the activity of poly(A) polymerase. It is suggested that the induction of this enzyme may be generally involved in cell differentiation.
...
PMID:Induction of polyadenylate polymerase and differentiation in neuroblastoma cells. 17 99

Upon exposure to the carcinogens N-acetoxy-N-2-acetylaminofluorene and 7-bromomethyl-benz[a]anthracene, which bind covalently to DNA, ether-permeabilized (nucleotide-permeable) Escherichia coli wild-type cells responded with DNA excision repair. This repair was missing in mutants carrying defects in genes uvrA, uvrB and uvrC, whereas it was present in uvrD and several rec mutants. Enzymic activities involved were identified by measuring repair polymerization and size reduction of denatured DNA. 1. An easily measurable effect in E. coli wild-type cells was carcinogen-induced repair polymerization. When initiated by N-acetoxy-N-2-acetylaminofluorene or 7-bromomethyl-benz[a]anthracene, it depended upon an ATP-requiring step; CTP, GTP or UTP did not substitute for ATP. DNA repair synthesis was inhibited by p-chloromercuribenzoate and quinacrine. In uvrA, uvrB and uvrC mutants no carcinogen-stimulated DNA synthesis could be detected, indicating that steps involved in pyrimidine dimer excision are also involved in chemorepair. In recA, recB and recC mutant cells, repair synthesis was stimulated by the carcinogens to a normal extent. This evidence excludes the ATP-dependent recB,C deoxyribonuclease and recA gene products as playing an important role in carcinogen-induced excision repair. polA1 cells showed drastically reduced levels of rapair polymerization, indicating that DNA polymerase I is the main polymerizing enzyme. 2. As determined by DNA size reduction in alkaline sucrose gradients, the arylalkylating carcinogens caused endonucleolytic cleavage of endogenous DNA in wild-type cells. This incision step was most effectively performed in the presence of ATP; UTP, CTP and GTP were only slightly effective. Incision was inhibited by p-chloromercuribenzoate and quinacrine. When exposed to the arylalkylating carcinogens, uvrA, uvrB and uvrC mutant cells did not perform the incision step in the presence of ATP, suggesting the involvement of the respective gene products in the initiation of chemorepair.
...
PMID:Carcinogen-induced DNA repair in nucleotide-permeable Escherichia coli cells. Analysis of DNA repair induced by the carcinogens N-acetoxy-N-2-acetylaminofluorene and 7-bromomethyl-benz(a)anthracene. 76 31

Nuclei from seminal vesicle epithelium of adult guinea pigs were isolated in hypertonic sucrose solution. The incorporation of [3H]UTP by the isolated nuclei into acid-precipitable products was studied. Incorporation required ATP, GTP, CTP, UTP, and Mg+2. It was inhibited by addition of actinomycin D, deoxyribonuclease, or pyrophosphate to the reaction mixture. Thus, incorporation of [3H]UTP by isolated nuclei had the same characteristics that have been demonstrated for the reactions catalyzed by nuclear RNA polymerases. Using alpha-amanitin as a metabolic tool, we established concentrations of (NH4)2SO4. Mg+2, and nucleotides that give maximum assayable activities of nuclear RNA polymerases I and II. When the activities of polymerases I and II were measured in isolated seminal vesicle nuclei of guinea pigs that had been castrated 4 days earlier, a marked decrease in activities was found relative to control values (nuclei from intact animals). No further decrease was found 8 days after castration. Diminished accessibility to the nuclear DNA template and a decrease in the concentration of RNA polymerase molecules seemed to be responsible for the observed effects of castration on activities of RNA polymerases. An increase in ribonuclease activity did not seem to be responsible for the effects of castration. Activities of the enzymes did not change 2, 3, or 4 hours after intraperitoneal injection (2 mg/kg body weight) of each of five different androgens. Similarly, a single intraperitoneal injection of testosterone did not restore enzyme activity of polymerade I or II at any time during the first 24-hour period after hormone administration.
...
PMID:RNA polymerase activities in isolated nuclei of guinea pig seminal vesicle epithelium: influence of castration and androgen administration. 90 9

Epithelial and stromal cells were isolated from endometrium of Day 1 pseudopregnant rabbits by enzymatic digestion with trypsin or trypsin:collagenase:deoxyribonuclease. Dispersed cells were grown in RPMI 1640 supplemented with 10% whole or steroid-depleted fetal bovine serum (FBS). Epithelial and stromal cells reached confluency after 6 to 7 days in culture and showed specific characteristics. Cells could be differentiated according to morphology, growth patterns, electrophoretic patterns, and response to estrogen or progesterone. Hormonal stimulation of adenylate cyclase activity was measured in broken cell preparations by catalytic transformation of alpha-32P-adenosine triphosphate into 32P-adenosine 3'-5' cyclic monophosphate (cAMP). Adenylate cyclase activity was present in fresh endometrial tissue and in dispersed cells after 7 days in culture. The enzyme activity was significantly higher in stromal than in epithelial cells at all stimulation levels: basal (9.2 +/- 1.0 vs. 2.3 +/- 0.6, p less than 0.001) and guanosine triphosphate (GTP, 300 microM) (25.4 +/- 2.9 vs. 7.0 +/- 1.6, p less than 0.001). Net response to prostaglandin E2 (PGE2, 10 microM) was three times higher (p less than 0.001) in stromal (17 +/- 2) than in epithelial (5.0 +/- 1) cells. These results suggest that PGE2 can stimulate adenylate cyclase in rabbit endometrium and that the enzyme is preferentially localized in the stroma. Our results are in agreement with the hypothesis that cAMP formed in endometrium in response to PGE2 might be involved in the decidual reaction.
...
PMID:Cell-specific localization of prostaglandin E2-sensitive adenylate cyclase in rabbit endometrium. 347 35

A cytosolic factor that stimulates transcription in isolated nuclei was purified approximately 4000-fold to near homogeneity from rat liver. The molecular weight of the factor was determined as 47 000 by SDS-polyacrylamide gel electrophoresis. The factor had no detectable deoxyribonuclease and protease activity but showed ribonuclease inhibitor activity. The factor could stimulate transcription in isolated nuclei by 50% at about 3.0 ng and the maximal stimulation was about 100%. When [gamma-S]ATP and [gamma-S]GTP were included in the reaction, the factor stimulated the synthesis of RNA which was able to bind to a mercury-Sepharose column and about 80% of the bound RNA was sensitive to a low concentration of alpha-amanitin. When heparin was added before initiation to preincubation mixture containing RNA polymerases II and DNA, a small but definite incorporation of [14C]UTP was observed. The factor alone had no stimulatory effect on the heparin-resistant incorporation of [14C]UTP but, in the presence of two rat liver nuclear fractions, phosphocellulose 0.5 and 1 M KCl step fractions, could stimulate the incorporation above the level with the combination of the two nuclear fractions. Antibody raised against the factor inhibited accurate transcription from the adenovirus 2 major late promoter in a nuclear lysate from Ehrlich ascites tumor cells, and the inhibition was neutralized by the factor.
...
PMID:Purification of a cytosolic factor from rat liver that stimulates transcription in isolated nuclei and its action on purified RNA polymerase II-DNA system. 407 43

Rat liver mitochondria isolated in sucrose-N-tris(hydroxymethyl)methyl-2-aminoethane-sulphonic acid (TES) incorporated [(3)H]UTP into RNA for 1h. Incorporation was inhibited 50% by 1mug of actinomycin D/ml, 1mug of acriflavine/ml and 0.5mug of ethidium bromide/ml but was insensitive to rifampicin, rifamycin SV, streptovarcin and deoxyribonuclease. After the first 10min of incubation, the synthesis was insensitive to ribonuclease. RNA synthesis by mitochondria isolated in sucrose-EDTA was insensitive to actinomycin D and sensitive to ribonuclease during the first 10min of the incubation but thereafter the sensitivities were the same as for mitochondria isolated in sucrose-TES. In a hypo-osmotic medium the relative extent of incorporation of the four ribonucleoside triphosphates into RNA was CTP>UTP=ATP>>GTP. In an iso-osmotic medium the incorporation of CTP and GTP decreased. All four nucleotides were incorporated into RNA in a DNA-dependent process, as indicated by the inhibition by actinomycin D. In addition, CTP and ATP were incorporated into the CCA end of mitochondrial tRNA. ATP was also incorporated into an unidentified acid-insoluble compound, which hydrolysed in alkali to a product that was not ATP, ADP or 5'- or 2(3')-AMP. Atractyloside inhibited the incorporation of ATP into RNA with 50% inhibition at 2-3nmol/mg of protein. The [(3)H]UTP-labelled RNA had peaks of 16S and 13S characteristic of mitochondrial rRNA. In addition a peak at 20-21S was observed as well as heterogeneous RNA sedimenting throughout the gradient. The synthesis of all these species was inhibited by actinomycin D, indicating that rat liver mitochondrial DNA codes for mitochondrial rRNA as well as other as yet unidentified species.
...
PMID:Synthesis of ribonucleic acid by isolated rat liver mitochondria. 440 94

1. The 105000g supernatant fraction of rat liver catalyses the incorporation of ribonucleotides from ribonucleoside triphosphates into polyribonucleotide material. The reaction requires Mg(2+) ions and is enhanced by the addition of an ATP-generating system and RNA, ATP, UTP and CTP but not GTP are utilized in this reaction. In the case of UTP, the product is predominantly a homopolymer containing 2-3 uridine residues, and there is evidence that these may be added to the 3'-hydroxyl ends of RNA or oligoribonucleotide primers. 2. The microsome fraction of rat liver incorporates ribonucleotides from ATP, GTP, CTP and UTP into polyribonucleotide material. This reaction requires Mg(2+) ions and is enhanced slightly by the addition of an ATP-generating system, and by RNA but not DNA. Supplementation of the reaction mixture with the three complementary ribonucleoside 5'-triphosphates greatly increases the utilization of a single labelled ribonucleoside 5'-triphosphate. The optimum pH is in the range 7.0-8.5, and the reaction is strongly inhibited by inorganic pyrophosphate and to a much smaller degree by inorganic orthophosphate. It is not inhibited by actinomycin D or by deoxyribonuclease. In experiments with [(32)P]UTP in the absence of ATP, GTP and CTP, 80-90% of (32)P was recovered in UMP-2' or -3' after alkaline hydrolysis of the reaction product. When the reaction mixture was supplemented with ATP, GTP and CTP, however, about 40% of the (32)P was recovered in nucleotides other than UMP-2' or -3'. Although the reactions seem to lead predominantly to the synthesis of homopolymers, the possibility of some formation of some heteropolymer is not completely excluded.
...
PMID:Chain extension of ribonucleic acid by enzymes from rat liver cytoplasm. 568 1

Linear simian virus 40 DNA has been transcribed in vitro with wheat germ RNA polymerase II. Transcription products have been fractionated on polyacrylamide gels and several discrete sized RNA bands are seen. The RNA band pattern is affected dramatically by deoxyribonuclease treatment during RNA isolation. This is because most of the RNA synthesized is covalently linked to DNA. This linkage has been demonstrated by density analysis in formaldehyde-CsCl gradients and by incorporation of alkali-stable ribonucleotides into DNA. The linear DNA templates transcribed were generated by treatment of circular DNA with restriction enzymes which, in addition to cutting once at a single primary site, were found also to produce single strand nicks at specific secondary sites. The discrete sized RNA bands observed result from initiation at these nicks and terminated at DNA ends. There are two modes of nick-dependent initiation. In one mode the 3'-hydroxyl terminus of the DNA at a single strand nick serves as a primer for the extension of an RNA chain. In a second mode de novo initiation of an RNA chain is promoted at the nick. RNAs which are not primed initiate predominantly with GTP. The catalytic action of wheat germ RNA polymerase II is similar to that of Escherichia coli core RNA polymerase which has also been shown to synthesize primarily RNA which is covalently linked to DNA.
...
PMID:Transcription of simian virus 40 DNA by wheat germ RNA polymerase II. Priming of RNA synthesis by the 3'-hydroxyl of DNA at single strand nicks. 624 89

Isolated nuclei incubated with [14C]protein hydrolysate are shown to incorporate labelled amino acids into the acid-insoluble fraction. Purified chromatin and the complex of DNA with firmly bound proteins possess similar ability. The optimum pH of the reaction is 6.5-7.0, 2 mM MgCl2 stimulates incorporation, the temperature optimum is 37-40 degrees C. Chloramphenicol depresses incorporation by 70%, puromycin by 40%, cycloheximide does not affect the chromatin activity. Incorporation does not depend on the presence of ATP or GTP, and is substantially inhibited by deoxyribonuclease but not by ribonuclease treatment of chromatin or of the nuclei. Specific activity of firmly bound chromatin non-histone proteins is higher than that of labile bound ones; histones are not labelled. After pronase treatment of proteins radioactivity changes to an acid-soluble state. The molecular weight of isolated labelled polypeptides is about 6000 as shown by gel filtration and the analysis of NH2-terminal amino acids. Labelled polypeptides firmly bound to DNA consist of 7-10 amino acids. Specific activity of proteins firmly bound to DNA increases linearly with the time of incubation of chromatin with [14C]protein hydrolysate, the activity curve of labile bound non-histone proteins has a distinct sygmoid character. The polypeptide-synthesizing activity of rat liver chromatin increases between 9 h and 21 h after partial hepatectomy. Irradiation with 800 rads 30 min before the operation prevents activation of amino acid incorporation. From nine amino acids studied alanine, methionine, lysine, tyrosine and arginine are not incorporated in the system described. Glutamic acid is polymerized most effectively. Glutamine, asparagine and glycine are incorporated 7-8 times less. The data are given indicating that the incorporation is not random when an amino acid mixture is present. Preincubation of chromatin with NAD+ but not with its analogues increases the polypeptide-synthesizing activity of chromatin. The activation is prevented by thymidine and nicotinamide. Storage (18 h at 2-4 degrees C) brings about a complete loss of the polypeptide-synthesizing activity of chromatin. The ability of 'old' chromatin to incorporate amino acids can be restored by preincubating it with NAD+. Storage of chromatin in the presence of 5 mM adenosine 3',5'-monophosphate (cAMP) does not result in decrease of the polypeptide-synthesizing activity. It is assumed that poly-(ADP-ribose) is the energy source for amino acid activation in the system described.
...
PMID:Polypeptide-synthesizing activity of eukaryotic chromatin. Properties, dependence on poly(ADP-ribose) and connection with the cell cycle. 737 37

After synthesis of short, nascent oligonucleotide in the presence of (32P)DNA, GTP, CTP, UTP and 3'dATP, one can excise with deoxyribonuclease a ternary complex of RNA polymerase, protected DNA and oligonucleotide, while the enzyme simply bound to the template is removed by increasing the ionic strength. This ternary complex is retained on nitrocellulose membranes. On polyacrylamide gel electrophoresis it migrates faster than RNA polymerase alone. The protected portion of the DNA is constituted of about 75 nucleotides. It might represent the sites for RNA initiation.
...
PMID:??? 1194 67


1 2 Next >>

---