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:3.1.21.1 (DNase)
7,655 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In small oocytes of Xenopus species, two sets of 5S RNA genes, oocyte-type and somatic-type, are fully activated. The 5S RNA transcripts are temporarily stored, half in association with TFIIIA to form a 7S particle, the other half in association with tRNA and two proteins (p48 and p43) to form a 42S particle. It has been established previously that TFIIIA binds to the internal control region of 5S RNA genes and promotes their transcription. Here we show that protein can be translocated from the 42S particles to 5S RNA genes, but only after treatment of the particles with ribonuclease. Nevertheless, once transferred, stable protein-DNA complexes are formed and DNase-protection experiments show that binding is specific to the gene promoter, covering exactly the same sequence as TFIIIA. The DNA-binding protein is identified as p48 which, after isolation by ion-exchange chromatography, will bind to 5S RNA genes in the absence of ribonuclease.
...
PMID:An alternative protein factor which binds the internal promoter of Xenopus 5S ribosomal RNA genes. 368 70

In order to construct an in vitro recombination system of T7 DNA, the reaction products of which resemble those in vivo in structure, T7 DNA-membrane complex which is free from concomitant DNase activity was purified from T7 phage-infected cells. T7-infected cells were lysed with T4 lysozyme/Brij58, and T7 DNA-membrane complex was purified through three successive density gradient centrifugations. The properties of the complex on exposure to defined nucleases and observation of the complex by electron microscopy revealed that in T7 DNA-membrane complex, both ends of a linear T7 DNA are bound with membrane components. A mixture of 32P-labeled T7 DNA-membrane complex and BU-labeled T7 DNA-membrane complex was incubated with T7 exonuclease and T7 DNA-binding protein, and the reaction products with intermediate density were purified. Most of the products were found to have structures similar to that of the recombination intermediate found in T7-infected cells upon electron microscopic examination.
...
PMID:Purification of bacteriophage T7 DNA-membrane complex and its application to the in vitro recombination reaction. 391 87

A new procedure has been developed for the isolation of the chromosome complex, termed chromatin, from Escherichia coli. The bacteria were subjected to low ionic strength and T4 lysozyme, followed by detergent treatment analogous to that employed for the isolation of eukaryotic chromosomes. The chromatin was an insoluble viscous material which contained approximately equal amounts of DNA and RNA. The protein content of the chromatin was almost three times greater than the nucleic acid content. Electron microscopy revealed that the chromatin was highly condensed, having multiple loops and beaded structures with various diameters. The chromatin could be completely solubilized by both micrococcal nuclease and DNAase I, whereas RNAase had no effect. The initial degradation by micrococcal nuclease resulted in the production of a DNA-protein particle, sedimentation coefficient 10S, and an RNA-protein complex of 24S. Further degradation led to a decrease in sedimentation coefficient of the DNA-protein complex, but not of the RNA-protein particle. The peak size of the DNA of the initial DNA-protein particle was approximately 2400 bp. The action of micrococcal nuclease also resulted in the production of several discrete RNA species of various sizes. Several low molecular weight proteins (12000-27000) were found in the DNA-protein complex. The DNA-binding protein HU was present in the undigested chromatin; varying amounts of HU were, however, detected in the DNA-protein and RNA-protein particles.
...
PMID:Isolation, properties and nucleolytic degradation of chromatin from Escherichia coli. 619 Sep 86

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.
...
PMID:Developmentally regulated nonhistone proteins: evidence for deoxyribonucleic acid binding role and localization near deoxyribonuclease I sensitive domains of precartilage cell chromatin. 628 99

We examined the kinetics and the nature of the association of two herpes simplex virus proteins, the major DNA-binding protein (ICP8) and the major capsid protein (ICP5), with the nuclei of infected cells. We defined a series of stages in the association of the ICP8 protein with the cell nucleus. (i) Immediately after synthesis, the protein was found in the cytoplasmic fraction but associated rapidly with the crude nuclear fraction. (ii) The initial association of ICP8 with the crude nuclear fraction was detergent sensitive but DNase resistant, and, thus, the protein was either bound to structures attached to the outside of the nucleus and had not penetrated the nuclear envelope or was loosely bound in the nucleus, (iii) At intermediate times, a low level of an intermediate form was observed in which the association of ICP8 with the nuclear fraction was resistant to both detergent and DNase treatment. The protein may be bound to the nuclear matrix at this stage. Inhibition of viral DNA synthesis caused the DNA-binding protein to accumulate in this form. (iv) At late times during the chase period, the association of ICP8 with the cell nucleus was resistant to detergent treatment but sensitive to DNase treatment. our results argue that at this stage ICP8 was bound to viral DNA. Thus, nuclear association of the DNA-binding protein did not require viral DNA replication. More important is the observation that there is a series of stages in the nuclear association of this protein, and, thus, there may be a succession of binding sites for this protein in the cell during its movement to its final site of action in the nucleus. The major capsid protein showed some similar stages of association with the cell nucleus but the initial association with the nucleus followed a lag period. Its early association with the crude nuclear fraction was also detergent sensitive but was resistant to detergent treatment at later times. Its association with the cell nucleus was almost completely resistant to DNase treatment at all times. Inhibition of viral DNA replication blocked the nuclear transport of this protein. Thus, these two viral proteins share some stages in nuclear transport, although their requirements for nuclear association are different.
...
PMID:Definition of a series of stages in the association of two herpesviral proteins with the cell nucleus. 628 5

The adenovirus-specific DNA-binding protein (DBP) has been shown to inhibit the hydrolysis of single-stranded DNA by a DNase isolated from KB cells, (Nass, K., and Frenkel, G.D. (1980). J. Virol. 35, 314-319). The specificity of the inhibition has now been investigated. The DBP inhibits the hydrolysis of single-stranded DNA by several different DNases (DNase II, KB DNase, S1 nuclease) under a variety of reaction conditions, but it has no effect on DNase I-catalyzed hydrolysis of single-stranded DNA. The DBP also inhibits the rate of hydrolysis of double-stranded DNA by KB DNase and DNase II, but has no effect on DNase I-catalyzed hydrolysis of this substrate. The DBP also inhibits the dephosphorylation of 5'-phosphoryl-terminated DNA by bacterial alkaline phosphatase but stimulates the phosphorylation of 5'-hydroxyl-terminated DNA by polynucleotide kinase.
...
PMID:DNase inhibition by the adenovirus DNA-binding protein exhibits specificity for the enzyme but not for the secondary structure of the DNA. 630 53

Nuclear extracts were prepared from cells infected with herpes simplex virus type 1 (HSV-1) and fractionated by sucrose gradient centrifugation to identify deoxyribonucleoprotein complexes involved in viral replication. Large amounts of an HSV-1 induced protein with a molecular weight of about 133,000 sedimented as a broad peak in the 25 S region of the gradient and cosedimented with 13 S DNA fragments. The sedimentation of both the protein and DNA decreased upon treatment of nuclear extracts with DNase. This result indicated that the protein and DNA were associated in deoxyribonucleoprotein complexes. The protein was identified as the HSV-encoded major DNA-binding protein ICP8 based on its molecular weight, its association with DNA in nuclear extracts, and its immunoprecipitation with monospecific antiserum and monoclonal antibody to ICP8. Deoxyribonucleoprotein complexes containing ICP8 could be immunoprecipitated from nuclear extracts. When DNA was extracted from these immunoprecipitates, fractionated by agarose gel electrophoresis, transferred to nitrocellulose paper, and hybridized to 32P-labeled HSV-1 or cell DNA, both HSV-1 and cell DNA sequences were identified. Cesium chloride gradient analysis of the immunoprecipitated DNA indicated that duplex DNA was present in the complexes. Thus, the major DNA-binding protein of HSV-1 is associated with both duplex HSV-1 and cell DNA in vivo.
...
PMID:Identification and characterization of deoxyribonucleoprotein complexes containing the major DNA-binding protein of herpes simplex virus type 1. 631 32

A deoxyribonuclease has been purified 570-fold from the 14-day-old chick embryos. The purified enzyme requires Mg2+ or Mn2+ ions for maximum activity. The optimum pH is 9.0 in 20 mM Tris-HCl buffer. Its isoelectric point is 6.7. NaCl and N-ethylmaleimide strongly inhibit the reaction. An apparent molecular weight of 45,000 is determined by sedimentation in a glycerol density gradient. The enzyme hydrolyzes denatured DNA 50 to 100 times more rapidly than duplex DNA. RNA and synthetic polyribonucleotides are not substrate for the enzyme. DNase A catalyzes the endonucleolytic and exonucleolytic cleavages of single-stranded DNA. The enzyme produces DNA fragments having 70 to 100 nucleotides long at early time of reaction and then degrades these DNA fragments to acid-soluble materials, of which more than 70% is mononucleotides. In the exonucleolytic attack, the enzyme initiates hydrolysis of a single-stranded DNA from 5' to 3' direction. Chick embryo DNA-binding protein gives an intensive effect on the DNase A reaction by inhibiting the endonuclease activity rather than exonuclease activity under the standard assay conditions.
...
PMID:Deoxyribonuclease A of chick embryo. Partial purification and characterization of the enzyme. 682 17

The adenovirus-specific DNA-binding protein was isolated from adenovirus type 5-infected KB cells and shown to possess DNase inhibitor activity. The protein decreased the rate of hydrolysis of single-strand DNA proportionately to its concentration in the reaction. Two peaks of activity were obtained upon sedimentation in a glycerol gradient, probably corresponding to the two major adenovirus-specific polypeptides in the preparation (molecular weights, 72,000 and 44,000). The DNase inhibitor activity of the adenovirus DNA-binding protein was distinguishable from that of the cellular DNA-binding protein, which we have described previously (K, Nass and G. D. Frenkel, J. Biol. Chem. 254:3407-3410, 1979), by its pattern of sedimentation and by the effect of temperature on the two activities. For the adenovirus DNA-binding protein, the ratio of DNase inhibitor activity at 43 degrees C to that at 30 degrees C was approximately 14, whereas for the cellular protein this ratio was less than 3. The DNase inhibitor activity with the temperature coefficient of 14 was absent from cells infected with adenovirus type 5 ts125 at 40 degrees C. DNase inhibition is a simple, sensitive, quantitative method for assay of the adenovirus DNA-binding protein.
...
PMID:Adenovirus-specific DNA-binding protein inhibits the hydrolysis of DNA by DNase in vitro. 689 23

Recent studies suggest that anti-DNA antibodies may arise from the immune response to a complex of DNA and a DNA-binding protein. One of the protein targets frequently recognized by anti-DNA antibodies is the enzyme DNAase I. To investigate the possible role of DNAase I in the induction of anti-DNA antibodies, we immunized mice with a complex of DNA and DNAase I. Mammalian double strand DNA was crosslinked with DNAase I by ultraviolet light (UV) treatment and emulsified in complete Freund's adjuvant. BALB/c mice were immunized at the base of the tail with the DNA-DNAase complex, boosted after 2 weeks with the immunogen in incomplete adjuvant and bled one week after the boost. Control mice received UV treated DNA in adjuvant. In one-third of the mice immunized with the DNA-DNAase complex, IgG anti-DNA antibodies were detectable in serum; the antibodies reacted with single and double strand DNA. No anti-DNA response was elicited by immunization with DNA alone. These data show that immunization with a DNA-DNAase complex can induce anti-DNA antibodies in non-autoimmune mice strains and suggest that DNA-binding proteins may act as carriers in the immune response that leads to anti-DNA antibody production.
...
PMID:Induction of anti-DNA antibodies in non autoimmune mice by immunization with a DNA-DNAase I complex. 777 6


<< Previous 1 2 3 4 Next >>

---