Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.27.1 (RNase)
 16,360 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

There is a significant difference in the ability of human influenza A virus H1N1 strains isolated up to 1977 and those isolated later to rescue temperature-sensitive mutants of fowl plague virus with a defect in the nucleoprotein (NP) gene. Therefore the NP genes of five human H1N1 and H3N2 influenza A virus strains, isolated between 1950 and 1978, have been sequenced. By comparison with previous and more recent isolates, an evolutionary pathway has been established. Three amino acid replacements were found which might be responsible for the functional difference between the USSR (1977) and the Brazil (1978) strains. The California (H1N1) strain isolated in 1978 had acquired by reassortment the NP gene of a human H3N2 virus circulating at about 1977 as had been previously suggested by investigations involving RNase fingerprint or hybridization techniques.
J Gen Virol 1989 Aug
PMID:Biological and genetic evolution of the nucleoprotein gene of human influenza A viruses. 276 32

Extracts of Rad+ and radiation-sensitive (rad) mutants of the yeast Saccharomyces cerevisiae were examined for total Mg2+-dependent alkaline deoxyribonuclease activity and the presence of a nuclease that crossreacts immunologically with an antiserum raised against an endo-exonuclease from Neurospora crassa, an enzyme exhibiting both deoxyribo- and ribonuclease activities. No significant differences were observed in total deoxyribonuclease activity between Rad+ and rad mutants. The antibody precipitable activity, however, was found to be 30%-40% of the total alkaline deoxyribonuclease activity in logarithmically growing Rad+ cells. Extracts of stationary phase cells were lacking in antibody precipitable activity. Using immunoblot methods, a 72 kDa crossreacting protein was identified from logarithmically growing cells that was absent from stationary phase cells. In all radiation-sensitive mutants examined, except rad52, at least 20% of total activity was precipitable. Extracts from logarithmically growing rad52 mutants, including a rad52::LEU2 insertion mutant, exhibited less than 10% of the Rad+ precipitable activity; however, some crossreacting material was detected. Although, the level of endo-exonuclease activity is influenced by the RAD52 gene, it is not the product of this gene. The total deoxyribonuclease and the antibody precipitable endo-exonuclease activities were also followed during meiosis. Unlike the Rad+ strain which had previously been shown to have increased levels of total and immunoprecipitable endo-exonuclease as cells underwent meiosis, the rad52 mutant exhibited no increases in either category of nuclease activity. Given the importance of the RAD52 gene in repair, recombination and mutagenesis, the endo-exonuclease may be a significant component of these processes.
Mol Gen Genet 1988 Jan
PMID:An endo-exonuclease activity of yeast that requires a functional RAD52 gene. 283 Apr 67

Variation in the length of the 5' non-coding region of mitochondrial gene transcripts could result from multiple transcription initiation sites or post-transcriptional processing events. To distinguish between these possibilities, we have utilized the in vitro capping reaction catalyzed by guanylyl transferase to specifically label the 5' end of primary, unprocessed transcripts. Hybridization of in vitro capped mtRNA to immobilized DNA from the 5' flanking regions of 26 S, 18 S and 5 S rRNA genes and two protein-coding genes, ATP synthase subunit 9 (atp9) and apocytochrome b (cob), identified regions where transcription initiates. Single-strand specific RNase treatment of in vitro capped RNA hybridized to immobilized DNA containing the 5' flanking sequences from cob and atp9 suggests that these genes have multiple transcription initiation sites. Direct mapping of transcription initiation sites for the rRNA genes indicated that single major transcription initiation sites exist at approximately 180 and 230 nucleotides upstream from the mature 26 S and 18 + 5 S rRNA genes, respectively. Labeling of processed transcripts bearing a 5' hydroxyl moiety with T4 polynucleotide kinase and subsequent hybridization to the rRNA genes indicated that the mature forms of the rRNA are processed.
Mol Gen Genet 1988 Mar
PMID:RNA processing and multiple transcription initiation sites result in transcript size heterogeneity in maize mitochondria. 289 71

Sodium bisulphite modification of foot-and-mouth disease virus (FMDV) RNA in solution indicates that the majority of the poly(C) tract in the RNA is single-stranded in concordance with previous results with encephalomyocarditis virus RNA. The reaction kinetics are biphasic; 60% of the cytidylic acid in the poly(C) tract reacts like synthetic poly(C), and the remainder with the kinetics of the cytidylic acid in the rest of the RNA. The reactivity of the poly(C) tract with poly(I) indicates that it is looped out and exposed in the RNA. The deamination reaction has also been used to investigate the structure of the replicative form (RF) and replicative intermediate (RI) isolated from infected cells. Analysis by gel electrophoresis of the long RNase A- and T1-resistant oligonucleotides of RI suggests that it has five single-stranded poly(C) tracts to every one which is base-paired. Bisulphite reactivity of the poly(C) tract and gel electrophoresis of the ribonuclease-resistant oligonucleotides of RF indicate that the poly(C) is base-paired to a poly(G) tract in this molecule. The presence of a poly(G) tract in RF and RI provides unequivocal evidence that the poly(C) is replicated via poly(G) in the negative strand.
J Gen Virol 1985 Sep
PMID:Analysis of the secondary structure of the poly(C) tract in foot-and-mouth disease virus RNAs. 299 83

The nucleic acid of chicken parvovirus-like particles showed sensitivity to DNase and S1 nuclease treatment and resistance to digestion with RNase. Viral DNA readily served as a template for self-primed conversion in vitro into a double-stranded form of about 5200 base pairs. There was no evidence for encapsidation of strands of opposite polarities. These findings confirm the taxonomic classification of chicken parvovirus-like particles as fowl parvovirus type 1 within the Parvovirus genus of the Parvoviridae.
J Gen Virol 1985 Oct
PMID:The genome structure of a new chicken virus identifies it as a parvovirus. 299 61

Three regulatory proteins are involved in the post-transcriptional control of arginine metabolism in Saccharomyces cerevisiae: ARGRI, ARGRII and ARGRIII. The 880 amino acid ARGRII protein, like some DNA binding proteins, possesses in its N-terminal sequence a cysteine-rich region that presents homology to the zinc binding region of Escherichia coli aspartate transcarbamylase. ARGRII also has a region of 90 amino acids that is 30% homologous to the E. coli ARGR repressor. Moreover a 87 amino acid long sequence of ARGRII contains three stretches with significant homology to some viral, bacterial and pancreatic RNases. We propose a model in which the RNase-like sequence could regulate the expression of arginine anabolic messenger RNAs.
Mol Gen Genet 1988 Jan
PMID:The yeast ARGRII regulatory protein has homology with various RNases and DNA binding proteins. 312 9

The genome of the autonomous parvovirus minute virus of mice (MVM) is organized in two overlapping transcription units: the genes coding for the two non-structural proteins (NS-1 ad NS-2) are transcribed from a promoter (P04) located at map unit 4, whereas the promoter controlling the capsid protein genes (P39) lies at map unit 39. We studied the effect of viral proteins on the activity of the P39 promoter in vivo. By site-directed mutagenesis we constructed clones encoding only one of the two NS proteins. The activity of the P39 promoter was measured in HeLa or EL-4 cells transfected with these clones, either by an RNase protection assay or by following the expression of a reporter gene, CAT (which codes for chloramphenicol acetyltransferase), placed under the control of this promoter. We found that the P39 promoter of strain MVMi is activated in trans by a viral gene product, and evidence to suggest that NS-1 is the only viral gene product responsible for this trans-activation. We also determined that the mechanism of trans-activation is very rapid, since all species of viral mRNAs appear together in non-synchronized infected EL-4 cells within a 2 h interval.
J Gen Virol 1988 Oct
PMID:Minute virus of mice non-structural protein NS-1 is necessary and sufficient for trans-activation of the viral P39 promoter. 317 51

The primary structures of the immunity (Imm) and lysis (Lys) proteins, and the C-terminal 205 amino acid residues of colicin E8 were deduced from nucleotide sequencing of the 1,265 bp ClaI-PvuI DNA fragment of plasmid ColE8-J. The gene order is col-imm-lys confirming previous genetic data. A comparison of the colicin E8 peptide sequence with the available colicin E2-P9 sequence shows an identical receptor-binding domain but 20 amino acid replacements and a clustering of synonymous codon usage in the nuclease-active region. Sequence homology of the two colicins indicates that they are descended from a common ancestral gene and that colicin E8, like colicin E2, may also function as a DNA endonuclease. The native ColE8 imm (resident copy) is 258 bp long and is predicted to encode an acidic protein of 9,604 mol. wt. The six amino acid replacements between the resident imm and the previously reported non-resident copy of the ColE8 imm ([E8 imm]) found in the ribonuclease-producing ColE3-CA38 plasmid offer an explanation for the incomplete protection conferred by [E8 Imm] to exogenously added colicin E8. Except for one nucleotide and amino acid change in the putative signal peptide sequence, the ColE8 lys structure is identical to that present in ColE2-P9 and ColE3-CA38.
Mol Gen Genet 1987 Oct
PMID:Nucleotide sequences from the colicin E8 operon: homology with plasmid ColE2-P9. 332 26

From 380S particles of Berne virus (proposed family Toroviridae) one species of polyadenylated RNA was isolated. Using agarose gel electrophoresis its length was estimated as 20 kb or greater. When assayed under hypertonic transfection conditions genomic RNA was found to be infectious; RNase treatment destroyed the infectivity. The positive polarity of the molecule was confirmed by filter spot hybridization using cDNA prepared against poly(A)-selected RNA from infected cells. In embryonic mule skin cells infected with Berne virus the presence of five virus-specific, polyadenylated RNA species of 7.5, 2.1, 1.4, 0.8 and at least 20 kb was demonstrated. In vitro translation of the 7.5, 2.1 and 0.8 kb RNAs followed by immunoprecipitation showed that they encode a 151K product (possibly the precursor to the peplomer proteins), the envelope protein and the nucleocapsid protein, respectively.
J Gen Virol 1988 Sep
PMID:Characterization of Berne virus genomic and messenger RNAs. 341 Dec 97

Fusion between purified [3H]uridine-labelled West Nile virus (WNV) particles and liposomes containing RNase, was assayed by degradation of the viral RNA to trichloroacetic acid-soluble material. Fusion of virus with liposomes containing phosphatidylcholine, phosphatidylethanolamine, sphingomyelin and cholesterol (at a molar ratio of 1:1:1:1.5) was found to be dependent on pH with maximum fusion occurring at pH 6.7 and below. At pH 6.6 fusion was rapid and was essentially complete within 2 min at 37 degrees C. At this time, approximately 50% of the viral RNA had been degraded and increasing the concentration of liposomes or time allowed for fusion increased this percentage only slightly. Fusion was dependent on temperature, was almost totally non-leaky and was not dependent on the presence of divalent cations. The lipid composition of liposomes was found to influence both the pH optimum for fusion and the maximum degree of fusion observed. Electron microscopy was used to visualize the fusion reaction between liposomes and virus particles.
J Gen Virol 1986 Jan
PMID:pH-dependent fusion between the flavivirus West Nile and liposomal model membranes. 394 82


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