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

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Query: EC:3.1.26.9 (ribonuclease)
6,589 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The S-peptide and S-protein fragments of ribonuclease S (RNase S, no EC no. assigned) have been immobilized onto separate Sepharose gels via a "leash" of polycytidylic acid substrate. Each of these gels releases its RNase fragment when treated with the complementary enzyme fragment or with RNase A (EC 3.1.27.5), and the released fragments recombine to give RNase S activity. Thus this system provides substrate-leash amplification (SLA), such that more enzymatic activity is eluted from the system than is applied. For example, 100 pg of RNase applied to the S-peptide gel is amplified by 1.9 X 10(4) to the equivalent of 1.9 micrograms of activity in 20 h, when followed by combination of the released S-peptide with excess S-protein. We also tested a three-stage amplification system, with a pair of S-peptide and S-protein gels at each stage. In this system the cumulative amplification of the initial 1-ng dose of RNase A is 4.9, 52, and 25-fold after each stage, respectively. Only 2 mg of each SLA gel is used per stage in these experiments, reflecting the magnitude of their production of RNase S activity.
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PMID:Substrate-leash amplification with ribonuclease S-peptide and S-protein. 374 90

Bovine pancreatic ribonuclease (RNase) A and S protein (enzymatically inactive proteolytic fragment of RNase A which contains RNA binding site) stimulate the activation, as evidenced by increasing DNA-cellulose binding, of highly purified rat hepatic glucocorticoid-receptor complexes. These effects are dose dependent with maximal stimulation of DNA-cellulose binding being detected at approximately 500 micrograms (50 units of RNase A/mL). RNase A and S protein do not enhance DNA-cellulose binding via their ability to interact directly with DNA or to increase nonspecific binding of receptors to cellulose. Neither S peptide (enzymatically inactive proteolytic fragment which lacks RNA binding site) nor cytochrome c, a nonspecific basic DNA binding protein, mimics these effects. RNase A and S protein do not stimulate the conformational change which is associated with activation and is reflected in a shift in the elution profile of receptor complexes from DEAE-cellulose. In contrast, these two proteins interact with previously heat-activated receptor complexes to further enhance their DNA-cellulose binding capacity and thus mimic the effects of an endogenous heat-stable cytoplasmic protein(s) which also function(s) during step 2 of in vitro activation [Schmidt, T. J., Miller-Diener, A., Webb, M. L., & Litwack, G. (1985) J. Biol. Chem. 260, 16255-16262]. Preadsorption of RNase A and S protein to an RNase affinity resin containing an inhibitory RNA analogue, or trypsin digestion of the RNA binding site within S protein, eliminates the subsequent ability of these two proteins to stimulate DNA-cellulose binding of the purified receptors.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of bovine pancreatic ribonuclease A, S protein, and S peptide on activation of purified rat hepatic glucocorticoid-receptor complexes. 379 Apr 97

The antispermatogenic effect of seminal ribonuclease BS-1 was studied by injecting the substance intratesticularly, intraperitoneally, or subcutaneously in white mice. Selective damage was noted in 63% of seminal tubules after doses of 20 mcg (intratesticular) and in almost all the tubules after 50 mcg. Subcutaneous injections of 1.5 and 2.5 mg produced damage to 74% and 80% of the tubules, respectively, and intraperitoneal injections of 200 and 500 mcg produced damage to 35% and 88% of the tubules, respectively. RNase A and physiologic saline injections had no deleterious effect on any tubules in 20 animals. Examination of the liver, kidney, heart, spleen, skin, small intestine, bone marrow, and lung tissues of RNase BS-1 treated mice revealed no damage to any of these tissues. These results suggest that RNase BS-1 possesses a specific antispermatogenic effect in mice.
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PMID:[Anti-spermatogenic effect of seminal ribonuclease (BS-1 RNase)]. 437 1

1. Pancreatic ribonuclease in dilute EDTA has been shown to condition rough-microsomal membranes from adult rat liver to accept exogenously added rat liver polyribosomes in vitro at 0-4 degrees C. Treated smooth membranes would not significantly interact with polyribosomes. 2. The conditioning process decreased the membrane RNA content and removed polyribosomes from vesicle surfaces as viewed electron-microscopically. 3. Binding to these conditioned membranes was shown to be uninfluenced by changes of temperature (0-37 degrees C) and pH (6.9-7.8) or the presence of cell sap, but was inhibited by increasing the concentration of potassium chloride. 4. Possession of a polyribosome-binding capacity by conditioned rough membranes was not dependent on adventitious materials that could be dislodged by high ionic strengths. 5. Trypsin treatment under mild conditions destroyed the binding capacity of ribonuclease-conditioned rough membranes. 6. A 2-10S residual RNA was recovered from ribonuclease-conditioned membranes, but its partial removal had no effect on the capacity of membranes to accept polyribosomes. However, some role for this residual RNA in attaching polyribosomes could not be discounted. 7. Evidence is considered that polyribosome-binding sites are intrinsic features of conditioned membranes isolated from rough-microsomal fractions, and that long-range ionic bonding is a primary factor in polyribosome interaction with these binding sites.
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PMID:The association in vitro of polyribosomes with ribonuclease-treated derivatives of hepatic rough endoplasmic reticulum. Characteristics of the membrane binding sites and factors influencing association. 515 23

Pancreatic ribonuclease was irradiated in the dried state with electrons and then added to acetate buffer solutions that contained different concentrations of polyribonucleotides. Qualitatively similar results were obtained by adding a combination of unirradiated ribonuclease and lysozyme to such solutions. Such solutions scatter light strongly, and the intensity of the scattered light changes with time after mixing. The angular distribution of the scattered light was obtained as a function of time and compared with the rates at which hydrolysis products were formed. The turbidity of the solutions increases rapidly with time at the lower polyribonucleotide concentrations, and seems to result from a complex between inactive ribonuclease, or lysozyme, and oligonucleotides that appear during enzymic hydrolysis of the polynucleotides. The dissymmetry of the scattered light is approximately 5, indicating that the scattering centers are, if spherical, about 1500 A in diameter. The turbidities are remarkably high when one considers the low concentrations of protein and nucleic acid materials that are used.
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PMID:Dynamics of the interactions of basic proteins with polyribonucleotides. 563 35

Pancreatic ribonuclease forms large complexes with poly G in 0.1 M acetate buffer solutions (pH 5.4). These are largest when the ratio, of ribonuclease to poly G concentration, is slightly less than 2. Under the same conditions lysozyme forms still larger complexes with poly U, and these are largest when the ratio, of lysozyme to poly U concentration, is about 2.5. The ribonuclease in ribonuclease-poly G complexes digests poly U. Free ribonuclease digests the poly U in lysozyme-poly U complexes. However, when the poly G concentration is about an order of magnitude greater than that required to bind all the ribonuclease, lysozyme-bound poly U is not hydrolyzed.
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PMID:Pancreatic ribonuclease-poly G complexes: complete inhibition of poly U hydrolysis. 582 11

An endoribonuclease has been purified about 320-fold from the microsomes of rat liver. The enzyme had an apparent molecular weight of 54 000-58 000 and produced oligonucleotides, each consisting of 3-7 nucleotides from poly(A) and poly(U). No mononucleotide was obtained by the enzymatic hydrolysis of poly(A) and poly(U) under standard coditions. The relative rates of breakdown of synthetic polynucleotides by the enzyme under standard conditions were in the order poly(U) = poly(A) > poly(C). Divalent cations (Mg2+ or Mn2+) was required for the enzymatic activity, but monovalent cations (Na+, K+ or NH4+) inhibited the enzyme. The breakdown of poly(C) and poly(U) by the enzyme was inhibited by spermine, but that of poly(A) was not influenced by spermine. The enzyme was inhibited by p-chloromercuribenzoate and poly(G), but not by rat-liver ribonuclease-inhibitor and anti-RNase A serum.
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PMID:A microsomal endoribonuclease from rat liver. 624 72

Hantaan virus, the prototype virus of hemorrhagic fever with renal syndrome, was examined for nucleic acid characteristics which would support its previously proposed inclusion in the virus family Bunyaviridae. Nucleocapsid RNA from Hantaan virions and a control bunyavirus were examined for ribonuclease A (RNase A) sensitivity. Both viruses exhibited a similar accessibility of RNA within nucleocapsids to digestion by RNase A. Complete digestion of the RNA of both viruses was affected with high concentrations of ribonuclease. Evidence for negative strand RNA polarity was obtained by an in vitro transcriptase assay. RNA dependent RNA polymerase activity was associated with Hantaan virions. Polymerase activity required manganese and nucleoside triphosphates and was enhanced by magnesium, 2-mercaptoethanol, and sodium chloride. Oligonucleotide map analysis of the large (L), medium (M), and small (S) genome segments of Hantaan virus demonstrated that each RNA species was unique with respect to each other and was different from host cell ribosomal RNA. A common 3' terminal sequence of the three genome segments was determined to be 3' AUCAUCAUCUG. This sequence is different from those reported for viruses within the four recognized genera of the Bunyaviridae. Because all other data were consistent with nucleic acid characteristics of the Bunyaviridae, we propose a separate genus within the Bunyaviridae with Hantaan as its prototype virs.
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PMID:Analysis of Hantaan virus RNA: evidence for a new genus of bunyaviridae. 641 60

The isolation and characterization of the initial intermediates formed during the irreversible acid denaturation of enzyme Ribonuclease A are described. The products obtained when RNase A is maintained in 0.5 M HCl at 30 degrees for periods up to 20 h have been analyzed by ion-exchange chromatography on Amberlite XE-64. Four distinct components were found to elute earlier to RNase A; these have been designated RNase Aa2, Aa1c, Aa1b, and Aa1a in order of their elution. With the exception of RNase Aa2, the other components are nearly as active as RNase A. Polyacrylamide gel electrophoresis at near-neutral pH indicated that RNase Aa1a, Aa1b, and Aa1c are monodeamidated derivatives of RNase A; RNase Aa1c contains, in addition, a small amount of a dideamidated component. RNase Aa2, which has 75% enzymic activity as compared to RNase A, consists of dideamidated and higher deamidated derivatives of RNase A. Except for differences in the proteolytic susceptibilities at an elevated temperature or acidic pH, the monodeamidated derivatives were found to have very nearly the same enzymic activity and the compact folded structure as the native enzyme. Fingerprint analyses of the tryptic peptides of monodeamidated derivatives have shown that the deamidations are restricted to an amide cluster in the region 67-74 of the polypeptide chain. The initial acid-catalyzed deamidation occurs in and around the 65-72 disulfide loop giving rise to at least three distinct monodeamidated derivatives of RNase A without an appreciable change in the catalytic activity and conformation of the ribonuclease molecule. Significance of this specific deamidation occurring in highly acidic conditions, and the biological implications of the physiological deamidation reactions of proteins are discussed.
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PMID:Isolation and characterization of monodeamidated derivatives of bovine pancreatic ribonuclease A. 642 73

The proton magnetic resonance spectrum at 300 MHz of the histidine residues in a semisynthetic derivative of bovine pancreatic ribonuclease (RNase A) has been determined. The derivative RNase 1-118 . 111-124 was prepared by enzymically removing six residues from the COOH terminus of the protein (positions 119-124) and then complementing the inactive RNase 1-118 with a chemically synthesized peptide containing the COOH-terminal 14 residues of ribonuclease (RNase 111-124) [Lin, M.C., Gutte, B., Moore, S., & Merrifield, R.B. (1970) J. Biol. Chem. 245, 5169-5170]. Comparison of the line positions of the C(2)-1H resonances of these residues and of their pH dependence with those reported by other workers has allowed assignment of the resonances to individual residues, as well as the determination of individual pK values for histidine-12, histidine-105, and histidine-119. The assignment of histidine-119 was confirmed by the use of a selectively deuterated derivative. The titration behavior of all four histidine residues is indistinguishable from that observed by others for bovine pancreatic ribonuclease A. Partial dissociation of the noncovalent semisynthetic complex was evident at 30 degrees C, pH 4.0, 0.3 M NaCl; pertinent spectra were analyzed to provide an estimate of the association constant between the component chains under these conditions of 1.9 X 10(3) M-1.
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PMID:Characterization of the histidine proton nuclear magnetic resonances of a semisynthetic ribonuclease. 661 22


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