Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A system that exploits defective interfering (DI) RNAs of mouse hepatitis virus (MHV) for deciphering the mechanisms of coronavirus mRNA transcription was developed. A complete cDNA clone of MHV DI RNA containing an inserted intergenic region, derived from the area of genomic RNA between genes 6 and 7, was constructed. After transfection of the in vitro-synthesized DI RNA into MHV-infected cells, replication of genomic DI RNA as well as transcription of the subgenomic DI RNA was observed. S1 nuclease protection experiments, sequence analysis, and Northern (RNA) blotting analysis revealed that the subgenomic DI RNA contained the leader sequence at its 5' end and that the body of the subgenomic DI RNA started from the inserted intergenic sequence. Two subgenomic DI RNAs were synthesized after inserting two intergenic sites into the MHV DI RNA. Metabolic labeling of virus-specific protein in DI RNA replicating cells demonstrated that a protein was translated from the subgenomic DI RNA, which can therefore be considered a functional mRNA. Transfection study of gel-purified genomic DI RNA and subgenomic DI RNA revealed that the introduction of the genomic DI RNA, but not subgenomic DI RNA, into MHV-infected cells was required for synthesis of the subgenomic DI RNA. A series of deletion mutations in the intergenic site demonstrated that the sequence flanking the consensus sequence of UCUAAAC affected the efficiency of subgenomic DI RNA transcription and that the consensus sequence was necessary but not sufficient for the synthesis of the subgenomic DI RNA.
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PMID:A system for study of coronavirus mRNA synthesis: a regulated, expressed subgenomic defective interfering RNA results from intergenic site insertion. 165 85

Human hepatitis delta virus (HDV) RNA has been shown to contain a self-catalyzed cleavage activity. The sequence requirement for its catalytic activity appears to be different from that of other known ribozymes. In this paper, we define the minimum contiguous sequence and secondary structure of the HDV genomic RNA required for the catalytic activity. By using nested-set deletion mutants, we have determined that the essential sequence for the catalytic activity is contained within no more than 85 nucleotides of HDV RNA. These results are in close agreement with the previous determinations and confirmed the relative insignificance of the sequence at the 5' side of the cleavage site. The smallest catalytic RNA, representing HDV genomic RNA nucleotide positions 683 to 770, was used as the basis for studying the secondary structure requirements for catalytic activity. Analysis of the RNA structure, using RNase V1, nuclease S1 and diethylpyrocarbonate treatments showed that this RNA contains at least two stem-and-loop structures. Other larger HDV RNA subfragments containing the catalytic activity also have a very similar secondary structure. By performing site-specific mutagenesis studies, it was shown that one of the stem-and-loop structures could be deleted to half of its original size without affecting the catalytic activity. In addition, the other stem-and-loop contained a six base-pair helix, and the structure, rather than the sequence, of this helix was required for the catalytic activity. However, the structure of a portion of the stem-and-loop remains uncertain. We also report that this RNA can be divided into two separate molecules, which alone did not have cleavage activity but, when mixed, one of the RNAs could be cleaved in trans. This study thus reveals some features of the secondary structure of the HDV genomic RNA involved in self-catalyzed cleavage. A model of this RNA structure is presented.
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PMID:Sequence and structure of the catalytic RNA of hepatitis delta virus genomic RNA. 173 Oct 72

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 peplomer gene of feline infectious peritonitis virus (FIPV) strain 79-1146 was isolated from a genomic cDNA library by differential hybridization with RNA 2 and 3 as probes. From the nucleotide sequence a primary translation product of 1452 residues (Mr 160,472) was predicted, containing an N-terminal signal sequence, a C-terminal transmembrane segment and 35 potential N-linked glycosylation sites. By S1 nuclease analysis the 5' end of the presumptive RNA 2 body was located at about 30 nucleotides upstream from the initiating AUG codon. At approximately the same position a nine nucleotide sequence ACUAAACUU was found, which was also present 37 nucleotides downstream from the open reading frame. Comparison of the sequences of the FIPV, murine hepatitis virus and infectious bronchitis virus peplomer proteins showed about 27% overall homology, with most conservation in the C-terminal half.
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PMID:cDNA cloning and sequence analysis of the gene encoding the peplomer protein of feline infectious peritonitis virus. 331 91

A cDNA probe representing the genome of mouse hepatitis virus (MHV) strain A59 (MHV-A59) was used to measure nucleotide sequence homologies among murine and human coronaviruses and the SD and SK coronaviruses isolated by Burks et al. Since SD and SK were isolated by inoculation of multiple sclerosis (MS) central nervous system (CNS) tissue into mice or cultured mouse cells, it is important to determine their relationships to other murine and human coronavirus isolates. Our results indicate that SD and SK share almost complete nucleotide homology (approximately 90%) with MHV-A59 and generate subgenomic RNAs of the same sizes as MHV-A59. The human coronavirus (HCV) strains tested show less homology with MHV-A59. The immunologically unrelated HCV-229E shows no nucleotide homology with MHV-A59. The immunologically cross-reactive HCV-OC43 shows nucleotide homology with MHV-A59 by blot hybridization but not when hybridized in solution and assayed by S1 nuclease digestion.
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PMID:Coronaviruses SD and SK share extensive nucleotide homology with murine coronavirus MHV-A59, more than that shared between human and murine coronaviruses. 668 65

By performing nonspecific polymerase chain reaction followed by elimination of chromosome-derived sequences, foreign DNA fragments were obtained from the serum of a patient with non-A-E hepatitis. One of the sequences, named NV-F, contained a partial open reading frame and was detected in 17 (24.6%) of 69 patients with non-A-E hepatitis, including 1 with fulminant hepatitis (vs. in 5 [2.8%] of 180 healthy individuals). A peptide was synthesized accordingly, to detect serum anti-NV-F antibody, which was found in 49 (75.4%) of 65 patients positive for NV-F. This DNA fragment was sensitive to S1 nuclease digestion. Cesium chloride gradient analysis revealed that the NV-F-associated particles had buoyant densities of 1.33-1.39 and 1.22-1.25 g/mL. Immunofluorescence analysis revealed that the novel antigen was present in the hepatocytes of patients infected with NV-F. In conclusion, we have identified a novel single-stranded DNA fragment derived from a virus-like agent associated with human hepatitis.
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PMID:Identification of a novel single-stranded DNA fragment associated with human hepatitis. 1654 49