Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.27.5 (RNase)
 17,967 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Previous studies showed that an antigen found in the circulation of animals heavily infected with Schistosoma mansoni was extracted in a trichloroacetic acid soluble-chloroform insoluble fraction (TCA-S-C) of adult worms. Antigenic activity was destroyed by periodate treatment but remained unaltered after treatment with proteolytic enzymes, DNase, RNase, and lyophilization. In the present study, chromatography of TCA-S-C on a DEAE cellulose column revealed six substances, one of which was antigenic. After electrophoresis in agarose antigenic activity corresponded to a slower moving, toluidine blue-staining material. A faster moving, toluidine blue-staining substance seems to be responsible for the large 260 nm, absorbing peak. Analysis of a fraction containing only antigen revealed a large amount of carbohydrate, primarily N-acetylglucosamine and D-glucuronic acid but also galactase, glucose, N-acetylglucosamine, and trace amounts of other sugars. Amino acids accounted for about 11% of the weight of the antigen. The antigen appears to be a proteoglycan.
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PMID:Further purification and characterization of a circulating antigen in schistosomiasis. 41 Aug 79

Allergen in crude extract of Dirofilaria immitis was purified and separated from IgG-inducing antigens by a combination of DEAE-Sephadex A-50 chromatography, Sephadex G-200 gel filtration and starch gel zone electrophoresis. The purified preparation was proved to be one protein band by sodium dodecyl sulfate polyacrylamide gel (SDS-gel) electrophoresis and one precipitin arc by immunodiffusion. The molecular weight of the purified allergen was estimated to be approximately 20,000 by gel filtration and 15,000 by SDS-gel electrophoresis. The carbohydrate content of the preparation was apparently low, about 2%. The allergen was positively charged, and its determinant group was protein in nature. It was resistant to tryptic, pepsic and chymotryptic digestion, periodate oxidation and DNase and RNase digestion but very sensitive to pronase digestion. Allergen was inclined to aggregate each other in the buffered solution. It was also very resistant to vibration, heat (80 degrees C for 1 h) and acid (pH 2.5) and alkali (pH 11.0) treatments. Rats as well as mice immunized with allergen developed only a reaginic antibody and no hemagglutination antibody.
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PMID:Immunological and physicochemical properties of a highly purified allergen from Dirofilaria immitis. 46 88

Adult mice were pulse labeled with tritiated thymidine [3H]TdR and killed 9 hr later. A low level incorporation of [3H]TdT into the nuclear DNA of Purkinje neurons was found in autoradiographs. Enzymatic digestions with DNase and with RNase in combination with autoradiographic grain counts indicate that a portion of nuclear DNA is not stable in the Purkinje nucleus. These results are discussed in light of reports of the stable nature of DNA in Purkinje neurons of adult mice.
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PMID:Low level incorporation of tritiated thymidine into the nuclear DNA of Purkinje neurons of adult mice. 47 85

During the first 10 days after peripheral deafferentation of the mouse olfactory bulb stereoselective binding of L-[3H]carnosine declines markedly. The initial phase of this decline is due to a decrease in binding site stereoselectivity, which is then followed by a loss of assayable binding sites. The specificity of inhibition of L-[3H]carnosine binding by various peptides is also altered after denervation. Competitive inhibitors of carnosine binding become less potent after denervation, while analogues which are not competitive inhibitors remain equipotent before and after denervation. Several carnosine analogues that are normally poor inhibitors become more potent after denervation. Treatment of bulb membranes with trypsin, RNase and hyaluronidase, but not DNase or collagenase, resulted in significant alterations in carnosine binding. L-, but not D-carnosine, protected the binding site from trypsin digestion, and induced additional binding in bulb membranes in a dose-and temperature-dependent fashion. Preincubation of membranes with L-carnosine also led to the induction of additional carnosine binding in membranes from cerebral cortex, cerebellum and deafferentated bulbs but not from muscle. Bulbs from newborn mice contain about one-half of the adult levels of binding and no significant sex differences in carnosine binding were detected in bulbs from adult rats. L-[3H]carnosine binding was two-fold higher in the anterior compared to the posterior portion of the bulb, but there were no significant differences in binding of opiate, GABA, alpha-adrenergic, muscarinic cholinergic, benzodiazepine of glutamic acid receptor ligands.
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PMID:L-[3H]Carnosine binding in the olfactory bulb. II. Biochemical and biological studies. 48 25

Though DNase does not contain any cysteine residues, incubation of the enzyme with 2-nitro-5-thiocyanobenzoic acid in the presence of Ca2+ at pH values above 7.5 results in an irreversible inactivation of the enzyme. The inactivation also occurs when Ca2+ is replaced by Mg2+, but not in their absence. Amino acid analyses after acid hydrolyses of the completely inactivated ant the native enzymes show no significant differences in composition, including tryptophan and half-cystine residues. However, sodium dodecyl sulfate gel electrophoresis indicates enzyme cleavage by the treatment with 2-nitro-5-thiocyanobenzoic acid. This reagent does not inactivate chymotrypsin and lysozyme, and under conditions where bovine DNase is inactivated, does not inactivate other nucleases such as ribonuclease, snake venom phosphodiesterase, and spleen acid DNase. However, it inactivates malt DNase and can, therefore, be considered a specific inhibitor of DNase I. The inactivation kinetics is pseudo-first order, resembling Michaelis-Menten, with an affinity constant of 16.7 mM. It is the cyano group, not the thionitrobenzoic acid of 2-nitro-5-thiocyanobenzoic acid that reacts to form cyano-DNase.
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PMID:Inactivation of bovine pancreatic DNase by 2-nitro-5-thiocyanobenzoic acid. I. A novel inhibitor for DNase I. 48 54

Tumor culture toxohormone (TCT) obtained from cultures of MBQA mouse tumor cells, a line derived from a methylcholanthrene-induced fibrosarcoma (CBA/J origin), suppressed the mitogenic responsiveness of mouse spleen cells (PHA, LPS) as well as the antibody formation to SRBC in vitro. The immunosuppressive activity of toxohormone was readily inactivated by heating at 100 degrees C or treatment with trypsin, but not by DNase and RNase treatment.
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PMID:Immunosuppression induced by "toxohormone" from mouse tumor cells in culture. 49 45

Semi-thin and ultrathin sections of locust testes have been incubated in 3H-actinomycin D solution and submitted to radioautography. The improved technical conditions described allow the reproducible obtainment of cell radioautographs with a moderate nuclear labelling and a very low nonspecific background which are usable for semi-quantitative results. Extraction with enzymes (DNase, RNase, pronase) or concentrated salt solution have been carried out before 3H-Actinomycin D treatment in order to characterize the reaction. The semi-quantitative results obtained at the light microscope level suggest that, in relation to the structural and chemical changes which occur in chromatin during spermiogenesis, some proteins may be easily hydrolysed in early spermatids. In ultrathin sections of spermatocytes the X chromosome is heavily "stained" with 3H-Actinomycin D, while 3H-uridine is not incorporated into the sex chromatin. These results are discussed in the light of current ideas on the constitution of active chromatin.
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PMID:3H-actinomycin D binding to ultrathin section of plastic-embedded Locusta migratoria testicular tubules. Improvement of the technique and further characterization of the reaction. 52 Mar 26

Administration of lead acetate (3.4 mg/100 g of body weight) by daily intraperitoneal route for 4 days in albino rats caused an increase in size of the liver and kidney. There was diminution of the protein content of the liver. Concentration of DNA decreased to a slight extent and protein/DNA ratio remained unaltered in liver and kidney. There was elevation of the concentration of RNA in both the organs. Protein/RNA ratio was reduced. RNA per unit amount of DNA was found to be increased and the activities of RNase and DNase in both the organs were reduced. There was also diminution of plasma protein level. The possible significance of these changes has been discussed.
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PMID:Effect of lead on certain aspects of protein metabolism. 52 60

Loose, fibrillar, spherical structures have been observed during recent years in interphase nuclei of both animal and plant cells. These nuclear formations have been referred to as karyosomes, fibrillar bodies, micropuffs and centromeres. In order to gain further information on the nature of these structures, a cytochemical and radioautographic investigation was undertaken using plant meristematic cells (Allium porrum). For that purpose roots were fixed with either formaldehyde or glutaraldehyde in order to carry out cytochemical tests for DNA, RNA and proteins. Certain of the preparations were also first digested with DNase, RNase or proteinase K and then stained according to different procedures. Other specimens were labelled with thymidine for high-resolution radioautographic observations. Staining with diaminobenzidine (DAB) revealed that these nuclear puff-like formations consisted partly of a loose fibrillar meshwork containing nucleic acids. Part of this fine fibrillar reticulum persisted whether the preparations were digested with DNase or RNase before staining with DAB, thus indicating that these nuclear structures contained both DNA and RNA. The fact that these formations incorporate thymidine furnished additional support for the view that they correspond to specific chromosome segments. Staining with ethanolic phosphotungstic acid or digestion of specimens with proteinase K showed that these loose fibrillar structures also consisted of proteins. Judging from their ultrastructure, their association with the chromatin reticulum as well as from their cytochemical characteristics, these nuclear formations most likely correspond to centromeres. In view of the presence of DNA within these structures, it is possible to distinguish them from other equally spherical nuclear formations, observed in certain plant species, that have generally been referred to as karyosomes or micronucleoli and that appear to consist of ribonucleoproteins.
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PMID:A cytochemical and radioautographic study of the ultrastructural organization of puff-like fibrillar structures in plant interphase nuclei (Allium porrum). 52 78

3H-Thymidine uptake of thymocytes from LPS-responder Balb/c mice in the presence of a submitogenic dose (0.5 microgram/ml) of con A in vitro was significantly enhanced by adding LPS (0.1 to 2.5 microgram/ml), while the uptake of thymocytes from LPS-nonresponder C3H/HeJ was not enhanced by LPS. However, "endotoxin soups," which were prepared from the supernatants of LPS-responder murine spleen cell cultures in the presence of LPS, clearly increased the incorporation of 3H-thymidine into C3H/HeJ thymocytes in the presence of this small amount of con A. The soup prepared from C3H/HeJ spleen cell cultures did not show any synergistic effect with con A. Even if the major histocompatibility between soup-producer cells and responder cells to con A was different, the soups were still effective. The active substance in the "endotoxin soups" was eluted through a Sepharose CL-4B column, and its molecular size was estimated to be about 20,000 daltons. The activity of the soups was destroyed by heating at 70 C for 30 min or at 80 C for 10 min. Digestion with trypsin destroyed the activity of the soups, but digestion with DNase or RNase did not. The role of the active substance in the soups in synergy with con A and its relation to the synergistic effect of con A and LPS are discussed.
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PMID:Lipopolysaccharide-induced mediators assisting the proliferative response of C3H/HeJ thymocytes to concanavalin A. 53 Jan 3


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