Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.30.1 (S1 nuclease)
 3,660 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Abnormal tubulofilamentous particles were identified by electron microscopy using a simple touch negative staining technique from brains of mice infected with four strains of the scrapie agent. Treatment by three proteolytic enzymes and subsequent treatment with DNase and mung bean nuclease of grids prepared from the infected animals confirmed previous observations that the tubulofilamentous particles observed in scrapie-effected brains are complex structures. The core of the tubulofilamentous particle scrapie-associated fibrils was revealed by treatment with SDS. Treatment with proteolytic enzymes and subsequent treatment with DNase or mung bean nuclease or S1 nuclease also revealed typical and transitional stages of scrapie-associated fibrils. However, treatment with RNase A had no effect. The data suggest that nucleic acid is a single-stranded DNA protected by a protein coat.
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PMID:Evidence of ssDNA in tubulofilamentous particles: their relationship to scrapie-associated fibrils. 167 41

We have developed a novel plasmid isolation procedure and have adapted it for use on an automated nucleic acid extraction instrument. The protocol is based on the finding that phenol extraction of a 1 M guanidinium thiocyanate solution at pH 4.5 efficiently removes genomic DNA from the aqueous phase, while supercoiled plasmid DNA is retained in the aqueous phase. S1 nuclease digestion of the removed genomic DNA shows that it has been denatured, which presumably confers solubility in the organic phase. The complete automated protocol for plasmid isolation involves pretreatment of bacterial cells successively with lysozyme, RNase A, and proteinase K. Following these digestions, the solution is extracted twice with a phenol/chloroform/water mixture and once with chloroform. Purified plasmid is then collected by isopropanol precipitation. The purified plasmid is essentially free of genomic DNA, RNA, and protein and is a suitable substrate for DNA sequencing and other applications requiring highly pure supercoiled plasmid.
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PMID:Plasmid purification by phenol extraction from guanidinium thiocyanate solution: development of an automated protocol. 171 49

The hepatitis delta virus can be found in the serum and liver of some hepatitis B virus patients. We now report that the RNA genome of serum-derived delta virus is single-stranded and circular. Livers of infected chimpanzees or woodchucks contained as many as 300,000 copies of genomic strand RNA per average cell, and at least some of this RNA had a circular conformation. Also present in the livers were RNA species complementary to the virion RNA. The genomic RNA was 5-22 times more abundant than this antigenomic strand. Some of the antigenomic RNA was complexed with genomic RNA, as evidenced by the fact that at least 34% of the antigenomic RNA was resistant to digestion with either RNase A in 0.3 M NaCl or S1 nuclease. Some of the antigenomic RNA was in a circular conformation. These and other findings showed that the structure and replication of hepatitis delta virus are in many ways similar to those of the previously described plant viroids, virusoids, and satellite RNAs.
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PMID:Structure and replication of the genome of the hepatitis delta virus. 243 Feb 99

The cytosolic untransformed molybdate-stabilized glucocorticoid-receptor complex from rat liver was eluted as a heterogenous peak containing two components with Stokes radii (Rs) of 8.3 nm and 7.1 nm when analyzed by size-exclusion HPLC even in the absence of molybdate. In contrast, the highly purified glucocorticoid receptor yielded a sharp symmetrical peak of Rs = 7.1 nm. We demonstrate that the 7.1-nm component could not result from a proteolytic degradation of the 8.3-nm receptor form. The same receptor heterogeneity was observed in thymus cytosol which contains less proteases than liver. After labeling with [3H]dexamethasone 21-mesylate and SDS/PAGE the same 94-kDa receptor band was revealed in both the 8.3-nm and 7.1-nm forms. Immunoblotting experiments showed that both the 94-kDa hormone-binding subunit and the 90-kDa heat-shock protein were present in the two different receptor forms. The 8.3-nm receptor form was converted to the 7.1-nm receptor form after treatment by ribonuclease A in the presence of molybdate and this effect was dose-dependent, being completely prevented by placental ribonuclease inhibitor (RNasin). In contrast, in the presence of molybdate, the 7.1-nm receptor form was ribonuclease-insensitive. Treatment of cytosol with RNase A in the absence of molybdate, partially shifted the untransformed receptor towards the 5.2-nm transformed receptor form. This effect was abolished by placental ribonuclease inhibitor. RNase S protein, an enzymatically inactive proteolytic fragment of RNase A, or S1 nuclease, which is specific for single-stranded nucleic acids, were ineffective when used instead of RNase A. In contrast, cobra venom endonuclease, which preferentially attacks double-stranded regions of small RNAs, caused a complete conversion of the 7-8-nm untransformed receptor to the 5.2-nm transformed receptor form. These results were not observed in the presence of molybdate. Addition of RNasin prior to heating cytosol in the absence of molybdate did not prevent the receptor from dissociating to the 5.2-nm form, suggesting that an endogenous RNase is not involved in the transformation process. The 7.1-nm receptor form was shifted to a 9.2-nm complex when incubated with an excess of GR 49 antireceptor antibody, whereas the 8.3-nm receptor form did not bind to the antibody.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:RNA binding to the untransformed glucocorticoid receptor. Sensitivity to substrate-specific ribonucleases and characterization of a ribonucleic acid associated with the purified receptor. 246 3

RNA-dependent RNA polymerase activities were detected in purified particles of white clover cryptic viruses 1 and 2. The polymerases of the two viruses had different requirements for optimum activity. Enzyme activity was dependent upon the presence of virus particles, Mg2+, and the four ribonucleoside triphosphates, and was insensitive to actinomycin D, alpha-amanitin, and rifampicin. The labeled reaction products were dsRNAs as indicated by CF 11 column chromatography and by their ionic-strength-dependent sensitivity to hydrolysis by RNase A and resistance to S1 nuclease. The dsRNAs synthesized in vitro had the same electrophoretic mobilities as the corresponding viral templates.
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PMID:RNA-dependent RNA polymerase activity in two morphologically different white clover cryptic viruses. 335 1

Partially purified carnation cryptic virus (CarCV) preparations possessed RNA-dependent RNA polymerase activity which was absent in comparable preparations from virus-free carnations. Enzyme activity was dependent upon the presence of virus particles, Mg2+, and the four ribonucleoside triphosphates, and was insensitive to inhibitors of DNA-dependent RNA polymerases. The 32P-labeled enzyme reaction products were largely dsRNAs as indicated by resistance to S1 nuclease and RNase A at high but not low ionic strength. The in vitro synthesized dsRNAs hybridized specifically with CarCV genomic dsRNAs, and the radioactive products present in the polymerase reaction mixture sedimented with the virus particles in sucrose density gradients. The data suggest that the RNA-dependent RNA polymerase associated with CarCV particles is a replicase which catalyzes the synthesis of copies of the genomic dsRNAs.
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PMID:In vitro synthesis of double-stranded RNA by carnation cryptic virus-associated RNA-dependent RNA polymerase. 338 65

The interaction of protein and RNA in composition of virion ribonucleoprotein (RNP) of influenza A virus was studied by treatment of this structure with hydrolytic enzymes: pancreatic RNase A, nuclease S1 and pronase. The results indicate that RNA in RNP does not shield proteins from the effect of pronase. The possibility of using this fact in the construction of a model RNP structure is discussed. No differences in the effect of RNase A and nuclease S1 on RNP were found which corresponded to the concept of the protective role of RNP protein in the process of RNA hydrolysis.
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PMID:[Action of hydrolytic enzymes on influenza virus A ribonucleoprotein]. 627 94

Escherichia coli translational initiation factor 3 (IF3) may be crosslinked to the 3' end of 16S RNA in 30S ribosomal subunits. In order to determine the sequence to which IF3 may bind in vivo, samples of 5'-32P labelled 3' terminal 49-nucleotide fragment of 16S RNA were incubated 5 min. at 37 degrees in 40 mM Tris-HOAc, pH 7.4, 100 mM NaCl, 1 mM Mg (OAc)2, 1 mM ZnSO4, with or without IF3, then reacted a further 5 min with nuclease S1, RNase T1, or RNase A. Base pairing between the 5' and 3' legs of the fragment occurs in the absence of IF3, but is disrupted by IF3 binding. IF3 appears to protect some residues near the 5' end of the fragment (U1495, A1499, A1500, A1502, and A1503) from nuclease S1, and potentiates S1 attack on others (G1494, G1497, C1501, G1504, G1505, U1506, G1517, G1529, G1530, and C1533). A series of equimolar reactions at increasing dilution imply an association constant range of 1.4-7.0 X 10(7) M-1.
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PMID:Nuclease mapping of the secondary structure of the 49-nucleotide 3' terminal cloacin fragment of Escherichia coli 16s RNA and its interactions with initiation factor 3. 634 66

The specificity of transcription of Euglena gracilis Z chloroplast DNA by chloroplast DNA-dependent RNA polymerase in a transcriptionally active chromosome (Hallick, R.B., Lipper, C., Richards, O.C., and Rutter, W.J. (1976) Biochemistry 15, 3039-3045) has been studied. RNA molecules are both initiated and elongated in vitro. The RNA transcripts have been characterized as to their size, nuclease sensitivity, 5'-terminal oligonucleotides, and coding locus on the chloroplast genome. RNA labeled in vitro at the 5' end with [gamma-32P]ATP was digested with RNase T1, RNase A, and S1 nuclease. The resulting 5'-gamma-32P-oligonucleotides were fractionated by gel electrophoresis. In each case, one or two discrete products were obtained, consistent with initiation in vitro only at defined loci. RNA labeled in vitro with [alpha-32P]ATP or CTP has been hybridized to Southern (Southern, E.M. (1975) J. Mol. Biol. 98, 503-517) transfers of restriction endonuclease fragments of chloroplast DNA. The most abundant in vitro transcripts hybridize to chloroplast DNA fragments coding for 23 S, 16 S, and 5 S rRNAs. Only the coding strands of the rRNA genes are transcribed. Non-rDNA sequences of chloroplast DNA are also selectively transcribed but at much lower levels. The transcriptionally active chromosome has proved to be an ideal biochemical preparation for the study of selective transcription of cell organelle DNA.
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PMID:Selective in vitro transcription of Euglena chloroplast ribosomal RNA genes by a transcriptionally active chromosome. 676 27

With the improved rapid sequencing techniques, the earlier sequence of U2 RNA of Novikoff hepatoma (Shibata et al, J. Biol. Chem. 250, 3909-3920, 1975) was reanalyzed and modified. The improved sequence of U2 RNA is 188 (or 189) nucleotides long and is in register with a characterized U2 RNA pseudogene (Denison et al, PNAS 78, 810-814, 1981) except for an 11 nucleotide sequence (nucleotides 147-157) which is absent from the pseudogene. From these results, a secondary structure of U2 RNA is proposed which is supported by the preferred cleavage sites with T1-RNase, RNase A and S1 nuclease. Isolated U2 RNA was cleaved by T1-RNase preferentially at positions 64 and 164, whereas U2 RNA in U2-snRNP was cleaved only at position 64, indicating that position 164 is protected in U2-snRNP. As with U1 RNA (Epstein et al, PNAS 78, 1562-1566, 1981) the 5'-end of isolated U2 RNA was not preferentially cleaved by T1-RNase.
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PMID:Primary and secondary structure of U2 snRNA. 679 40


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