RNA Virus InfectionsRNA Viruses: Viruses whose genetic material is RNA.DEAD-box RNA Helicases: A large family of RNA helicases that share a common protein motif with the single letter amino acid sequence D-E-A-D (Asp-Glu-Ala-Asp). In addition to RNA helicase activity, members of the DEAD-box family participate in other aspects of RNA metabolism and regulation of RNA function.Interferon-beta: One of the type I interferons produced by fibroblasts in response to stimulation by live or inactivated virus or by double-stranded RNA. It is a cytokine with antiviral, antiproliferative, and immunomodulating activity.Immunity, Innate: The capacity of a normal organism to remain unaffected by microorganisms and their toxins. It results from the presence of naturally occurring ANTI-INFECTIVE AGENTS, constitutional factors such as BODY TEMPERATURE and immediate acting immune cells such as NATURAL KILLER CELLS.RNA, Viral: Ribonucleic acid that makes up the genetic material of viruses.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Virus Replication: The process of intracellular viral multiplication, consisting of the synthesis of PROTEINS; NUCLEIC ACIDS; and sometimes LIPIDS, and their assembly into a new infectious particle.RNA: A polynucleotide consisting essentially of chains with a repeating backbone of phosphate and ribose units to which nitrogenous bases are attached. RNA is unique among biological macromolecules in that it can encode genetic information, serve as an abundant structural component of cells, and also possesses catalytic activity. (Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)RNA, Small Interfering: Small double-stranded, non-protein coding RNAs (21-31 nucleotides) involved in GENE SILENCING functions, especially RNA INTERFERENCE (RNAi). Endogenously, siRNAs are generated from dsRNAs (RNA, DOUBLE-STRANDED) by the same ribonuclease, Dicer, that generates miRNAs (MICRORNAS). The perfect match of the siRNAs' antisense strand to their target RNAs mediates RNAi by siRNA-guided RNA cleavage. siRNAs fall into different classes including trans-acting siRNA (tasiRNA), repeat-associated RNA (rasiRNA), small-scan RNA (scnRNA), and Piwi protein-interacting RNA (piRNA) and have different specific gene silencing functions.Vaccinia virus: The type species of ORTHOPOXVIRUS, related to COWPOX VIRUS, but whose true origin is unknown. It has been used as a live vaccine against SMALLPOX. It is also used as a vector for inserting foreign DNA into animals. Rabbitpox virus is a subspecies of VACCINIA VIRUS.Plant Viruses: Viruses parasitic on plants higher than bacteria.Virus Diseases: A general term for diseases produced by viruses.Virus Cultivation: Process of growing viruses in live animals, plants, or cultured cells.Receptors, Virus: Specific molecular components of the cell capable of recognizing and interacting with a virus, and which, after binding it, are capable of generating some signal that initiates the chain of events leading to the biological response.DNA Viruses: Viruses whose nucleic acid is DNA.RNA, Double-Stranded: RNA consisting of two strands as opposed to the more prevalent single-stranded RNA. Most of the double-stranded segments are formed from transcription of DNA by intramolecular base-pairing of inverted complementary sequences separated by a single-stranded loop. Some double-stranded segments of RNA are normal in all organisms.RNA Editing: A process that changes the nucleotide sequence of mRNA from that of the DNA template encoding it. Some major classes of RNA editing are as follows: 1, the conversion of cytosine to uracil in mRNA; 2, the addition of variable number of guanines at pre-determined sites; and 3, the addition and deletion of uracils, templated by guide-RNAs (RNA, GUIDE).RNA Splicing: The ultimate exclusion of nonsense sequences or intervening sequences (introns) before the final RNA transcript is sent to the cytoplasm.Sindbis Virus: The type species of ALPHAVIRUS normally transmitted to birds by CULEX mosquitoes in Egypt, South Africa, India, Malaya, the Philippines, and Australia. It may be associated with fever in humans. Serotypes (differing by less than 17% in nucleotide sequence) include Babanki, Kyzylagach, and Ockelbo viruses.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Viral Proteins: Proteins found in any species of virus.Influenza A Virus, H1N1 Subtype: A subtype of INFLUENZA A VIRUS with the surface proteins hemagglutinin 1 and neuraminidase 1. The H1N1 subtype was responsible for the Spanish flu pandemic of 1918.Virus Assembly: The assembly of VIRAL STRUCTURAL PROTEINS and nucleic acid (VIRAL DNA or VIRAL RNA) to form a VIRUS PARTICLE.Virus Shedding: The expelling of virus particles from the body. Important routes include the respiratory tract, genital tract, and intestinal tract. Virus shedding is an important means of vertical transmission (INFECTIOUS DISEASE TRANSMISSION, VERTICAL).Antiviral Agents: Agents used in the prophylaxis or therapy of VIRUS DISEASES. Some of the ways they may act include preventing viral replication by inhibiting viral DNA polymerase; binding to specific cell-surface receptors and inhibiting viral penetration or uncoating; inhibiting viral protein synthesis; or blocking late stages of virus assembly.Defective Viruses: Viruses which lack a complete genome so that they cannot completely replicate or cannot form a protein coat. Some are host-dependent defectives, meaning they can replicate only in cell systems which provide the particular genetic function which they lack. Others, called SATELLITE VIRUSES, are able to replicate only when their genetic defect is complemented by a helper virus.Measles virus: The type species of MORBILLIVIRUS and the cause of the highly infectious human disease MEASLES, which affects mostly children.Respiratory Syncytial Viruses: A group of viruses in the PNEUMOVIRUS genus causing respiratory infections in various mammals. Humans and cattle are most affected but infections in goats and sheep have also been reported.West Nile virus: A species of FLAVIVIRUS, one of the Japanese encephalitis virus group (ENCEPHALITIS VIRUSES, JAPANESE). It can infect birds and mammals. In humans, it is seen most frequently in Africa, Asia, and Europe presenting as a silent infection or undifferentiated fever (WEST NILE FEVER). The virus appeared in North America for the first time in 1999. It is transmitted mainly by CULEX spp mosquitoes which feed primarily on birds, but it can also be carried by the Asian Tiger mosquito, AEDES albopictus, which feeds mainly on mammals.Orthomyxoviridae Infections: Virus diseases caused by the ORTHOMYXOVIRIDAE.Rabies virus: The type species of LYSSAVIRUS causing rabies in humans and other animals. Transmission is mostly by animal bites through saliva. The virus is neurotropic multiplying in neurons and myotubes of vertebrates.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Respiratory Syncytial Virus Infections: Pneumovirus infections caused by the RESPIRATORY SYNCYTIAL VIRUSES. Humans and cattle are most affected but infections in goats and sheep have been reported.Simian virus 40: A species of POLYOMAVIRUS originally isolated from Rhesus monkey kidney tissue. It produces malignancy in human and newborn hamster kidney cell cultures.Influenza A Virus, H5N1 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 5 and neuraminidase 1. The H5N1 subtype, frequently referred to as the bird flu virus, is endemic in wild birds and very contagious among both domestic (POULTRY) and wild birds. It does not usually infect humans, but some cases have been reported.Vesicular stomatitis Indiana virus: The type species of VESICULOVIRUS causing a disease symptomatically similar to FOOT-AND-MOUTH DISEASE in cattle, horses, and pigs. It may be transmitted to other species including humans, where it causes influenza-like symptoms.Antigens, Viral: Substances elaborated by viruses that have antigenic activity.DNA-Directed RNA Polymerases: Enzymes that catalyze DNA template-directed extension of the 3'-end of an RNA strand one nucleotide at a time. They can initiate a chain de novo. In eukaryotes, three forms of the enzyme have been distinguished on the basis of sensitivity to alpha-amanitin, and the type of RNA synthesized. (From Enzyme Nomenclature, 1992).RNA, Ribosomal: The most abundant form of RNA. Together with proteins, it forms the ribosomes, playing a structural role and also a role in ribosomal binding of mRNA and tRNAs. Individual chains are conventionally designated by their sedimentation coefficients. In eukaryotes, four large chains exist, synthesized in the nucleolus and constituting about 50% of the ribosome. (Dorland, 28th ed)Antibodies, Viral: Immunoglobulins produced in response to VIRAL ANTIGENS.Genome, Viral: The complete genetic complement contained in a DNA or RNA molecule in a virus.Vero Cells: A CELL LINE derived from the kidney of the African green (vervet) monkey, (CERCOPITHECUS AETHIOPS) used primarily in virus replication studies and plaque assays.Hepatitis B virus: The type species of the genus ORTHOHEPADNAVIRUS which causes human HEPATITIS B and is also apparently a causal agent in human HEPATOCELLULAR CARCINOMA. The Dane particle is an intact hepatitis virion, named after its discoverer. Non-infectious spherical and tubular particles are also seen in the serum.Influenza A Virus, H3N2 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 3 and neuraminidase 2. The H3N2 subtype was responsible for the Hong Kong flu pandemic of 1968.Genes, Viral: The functional hereditary units of VIRUSES.RNA Interference: A gene silencing phenomenon whereby specific dsRNAs (RNA, DOUBLE-STRANDED) trigger the degradation of homologous mRNA (RNA, MESSENGER). The specific dsRNAs are processed into SMALL INTERFERING RNA (siRNA) which serves as a guide for cleavage of the homologous mRNA in the RNA-INDUCED SILENCING COMPLEX. DNA METHYLATION may also be triggered during this process.Cercopithecus aethiops: A species of CERCOPITHECUS containing three subspecies: C. tantalus, C. pygerythrus, and C. sabeus. They are found in the forests and savannah of Africa. The African green monkey (C. pygerythrus) is the natural host of SIMIAN IMMUNODEFICIENCY VIRUS and is used in AIDS research.RNA, Bacterial: Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.DNA, Viral: Deoxyribonucleic acid that makes up the genetic material of viruses.Hepacivirus: A genus of FLAVIVIRIDAE causing parenterally-transmitted HEPATITIS C which is associated with transfusions and drug abuse. Hepatitis C virus is the type species.Orthomyxoviridae: A family of RNA viruses causing INFLUENZA and other diseases. There are five recognized genera: INFLUENZAVIRUS A; INFLUENZAVIRUS B; INFLUENZAVIRUS C; ISAVIRUS; and THOGOTOVIRUS.

Comparative study of viral encephalopathy and retinopathy in juvenile sea bass Dicentrarchus labrax infected in different ways. (1/218)

The transmission of viral encephalopathy and retinopathy (VER) was investigated in juvenile sea bass (3 g) Dicentrarchus labrax by using cell culture supernatant (SSN-1 cell line) containing nodavirus. Five methods of infection were tested: intramuscular injection (IM), intraperitoneal injection (IP), oral infection, bath exposure and cohabitation of healthy fish with infected fish. Some differences were observed in time of disease onset and severity of symptoms depending on the mode of infection used. Clinical symptoms such as whirling swimming and lethargic or hyperactive behaviour were generally reproduced, except for fish infected via oral and IP infection. First mortalities occurred 3 d after IM and IP infection and 6 d after for the other modes of infection. Cumulative mortalities were also variable: 100% after IM infection, 10% after IP infection, 32% for bath exposure, 43% after cohabitation and 24% via oral infection. Histopathologically, vacuolation was observed in the central nervous tissues and in the retina. The observed lesions were more or less severe depending on the mode of infection, the sampling time and the organs: lesions on the surviving fish (42 days post infection, d p.i.) seemed to be generally more conspicuous in the retina than in the brain of the same fish. In most cases, the presence of nodavirus was confirmed in the same samples of brain and retina by immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR). The virus was not detected in other organs examined. The present results suggest that 2 forms of VER can be induced: IM injection leads to an acute form (severe nervous disorders with high and fast mortality) whereas oral infection, bath exposure and cohabitation induce a subacute form (less severe disorders and weak daily mortality). This experiment demonstrates experimentally induced horizontal transmission of VER in sea bass for the first time.  (+info)

Transmission of viral encephalopathy and retinopathy (VER) to yolk-sac larvae of the Atlantic halibut Hippoglossus hippoglossus: occurrence of nodavirus in various organs and a possible route of infection. (2/218)

The susceptibility of the Atlantic halibut Hippoglossus hippoglossus yolk-sac larvae to viral encephalopathy and retinopathy (VER) was investigated by waterborne challenge experiments with nodavirus. Transfer of VER was indicated by several lines of evidence. A significantly higher cumulative mortality was observed after challenge with virus compared to mock challenge, and increasing doses of virus resulted in shorter incubation periods. When the challenge was performed on the day after hatching, the time from inoculation to the time when 50% of the larvae were dead (LT50) ranged from 26 to 32 d. Postponement of challenge for 13 d reduced the LT50 to 14 d, indicating that the susceptibility of the larvae to the present nodavirus strain was low during the first 2 wk after hatching. The progression of the infection was monitored by sequential immunohistochemistry and electron microscopy. On Day 18 after hatching the initial signs of infection were observed as a prominent focus of immunolabelling in the caudal part of the brain stem. In the same larvae immunolabelled single cell lesions were observed in the stratified epithelium of the cranial part of the intestine. The portal of entry into the larvae may thus have been the intestinal epithelium, while the route of infection to the CNS may have been axonal transport to the brain stem through cranial nerves such as the vagus nerves. Later in the infection, lesions became more severe and widespread and were also found throughout the brain and spinal cord and in the retina, cranial ganglia, intestine, liver, olfactory epithelium, yolk-sac epithelium, gills and pectoral fins. The mortality in all virus-challenged groups was 100%. This study thus demonstrates that the present nodavirus strain is able to replicate and cause VER in Atlantic halibut yolk-sac larvae at temperatures as low as 6 degrees C.  (+info)

Pathogenesis of borna disease virus: granulocyte fractions of psychiatric patients harbor infectious virus in the absence of antiviral antibodies. (3/218)

Borna disease virus (BDV) causes acute and persistent infections in various vertebrates. During recent years, BDV-specific serum antibodies, BDV antigen, and BDV-specific nucleic acid were found in humans suffering from psychiatric disorders. Furthermore, viral antigen was detected in human autopsy brain tissue by immunohistochemical staining. Whether BDV infection can be associated with psychiatric disorders is still a matter of debate; no direct evidence has ever been presented. In the present study we report on (i) the detection of BDV-specific nucleic acid in human granulocyte cell fraction from three different psychiatric patients and (ii) the isolation of infectious BDV from these cells obtained from a patient with multiple psychiatric disorders. In leukocyte preparations other than granulocytes, either no BDV RNA was detected or positive PCR results were obtained only if there was at least 20% contamination with granulocytes. Parts of the antigenome of the isolated virus were sequenced, demonstrating the close relationship to the prototype BDV strains (He/80 and strain V) as well as to other human virus sequences. Our data provide strong evidence that cells in the granulocyte fraction represent the major if not the sole cell type harboring BDV-specific nucleic acid in human blood and contain infectious virus. In contrast to most other reports of putative human isolates, where sequences are virtually identical to those of the established laboratory strains, this isolate shows divergence in the region previously defined as variable in BDV from naturally infected animals.  (+info)

Molecular characterization of a ranavirus isolated from largemouth bass Micropterus salmoides. (4/218)

An iridovirus, isolated from largemouth bass Micropterus salmoides following a die-off among adult fish and provisionally designated largemouth bass virus (LMBV), was characterized by analysis of viral protein synthesis in infected cells, viral DNA restriction fragment length polymorphisms (RFLP), and sequence determination of the major capsid protein and viral DNA methyltransferase genes. All 3 approaches yielded results consistent with the suggestion that LMBV was a member of the genus Ranavirus. Moreover, LMBV was nearly identical to 2 isolates from Southeast Asia which had been previously detected in imported ornamental fish. It remains to be determined whether infection of largemouth bass resulted from exposure to an imported virus, or whether the presence of similar viruses in southeast Asia and the southeastern United States indicates that iridovirus species are not geographically limited as suggested earlier, but rather globally distributed.  (+info)

Emerging infectious diseases and amphibian population declines. (5/218)

We review recent research on the pathology, ecology, and biogeography of two emerging infectious wildlife diseases, chytridiomycosis and ranaviral disease, in the context of host-parasite population biology. We examine the role of these diseases in the global decline of amphibian populations and propose hypotheses for the origins and impact of these panzootics. Finally, we discuss emerging infectious diseases as a global threat to wildlife populations.  (+info)

Pathogenicity of nodavirus strains from striped jack Pseudocaranx dentex and Atlantic halibut Hippoglossus hippoglossus, studied by waterborne challenge of yolk-sac larvae of both teleost species. (6/218)

The present study shows that differences in pathogenicity exist among fish nodavirus strains. In challenge trials, a Japanese strain (SJ93Nag) was highly virulent to larvae of the striped jack Pseudocaranx dentex but replication was not detected in larvae of Atlantic halibut Hippoglossus hippoglossus at 6 degrees C. Conversely, a Norwegian nodavirus strain (AH95NorA) that was highly virulent to the Atlantic halibut larvae did not replicate in striped jack larvae at 20 degrees C. Occurrence of the disease viral encephalopathy and retinopathy (VER) and cumulative mortality were significantly different in the 2 species when challenged with the 2 nodavirus strains. The presence of nodavirus in nervous tissue was monitored by immunohistochemical methods. Our results support the view that the genetic diversity among nodavirus strains reflects the existence of different viral phenotypes which may be adapted to infect different host species and/or for replicating at different temperatures. Fish nodaviruses represent surveyable pathogens well suited for studying the relation between viral genotypic and phenotypic properties such as host specificity, temperature optima, neuroinvasiveness and neurovirulence.  (+info)

Surface disinfection of Atlantic halibut Hippoglossus hippoglossus eggs with ozonated sea-water inactivates nodavirus and increases survival of the larvae. (7/218)

Disinfection by ozonation of sea-water may reduce the risk of transmission of nodavirus, a major fish pathogen, via Atlantic halibut Hippoglossus hippoglossus eggs. In the present study, eggs at 4 d prior to hatching were exposed to nodavirus and then to ozonated sea-water using different concentrations (0.3 to 10 mg l-1) and exposure times (0.5 to 10 min). None of the larvae from virus-exposed eggs washed with ozonated sea-water developed viral encephalopathy and retinopathy (VER), which was detected in all dead larvae from eggs exposed to nodavirus but not washed with ozonated sea-water. In the non-treated control group about 20% of the dead larvae developed the disease. This suggests that the halibut eggs taken from a large-scale production facility were already contaminated with nodavirus. The egg groups which had been treated with 4 mg O3 l-1 for 0.5 min or with lower total ozone exposures had a higher survival and no adverse effects on the development of the larvae after hatching were observed. Although a slight delay in hatching was found, after 2 d the cumulative hatching had normalised. In the egg groups with high total exposure (4 mg O3 l-1 for 1 min or higher total ozone exposures) a pronounced negative effect on hatching was observed. Our results indicate that the egg surface may be important in the transfer of nodavirus and that nodavirus associated with the surface of the egg may be inactivated by ozonated sea-water.  (+info)

Enteric virus infections and diarrhea in healthy and human immunodeficiency virus-infected children. (8/218)

Forty-three stool samples from 27 human immunodeficiency virus (HIV)-seropositive children and 38 samples from 38 HIV-negative children, collected during a 15-month period, were examined for enteric viruses. Diagnostic assays included enzyme immunoassays for rotavirus, adenovirus, and Norwalk virus; polyacrylamide gel electrophoresis for picobirnavirus and atypical rotavirus; and PCR for astrovirus and enterovirus. Specimens from HIV-positive children were more likely than those of HIV-negative children to have enterovirus (56 versus 21%; P < 0.0002) and astrovirus (12 versus 0%; P < 0.02), but not rotavirus (5 versus 8%; P > 0.5). No adenoviruses, picobirnaviruses, or Norwalk viruses were found. The rates of virus-associated diarrhea were similar among HIV-positive and HIV-negative children. Enteroviruses were excreted for up to 6 months in HIV-positive children; however, no evidence for prolonged excretion of poliovirus vaccine was observed. These results suggest that although infection with enterovirus and astrovirus may be frequent in HIV-infected children, enteric viruses are not associated with the diarrhea frequently suffered by these children.  (+info)

  • 1996. Enhancement of resistance against Enterococcus seriolicida infection in yellowtail, Seriola quinqueradiata (Temminck & Schlegel), by oral administration of peptidoglycan derived from Bifidobacterium thermophylum. (ugm.ac.id)
  • Positive clones were further analysed by using them as hybridisation probes in Northern blots of total plant RNA and in Southern hybridisation with genomic DNA from Sorbus aucuparia leaves. (springer.com)
  • It has also been proposed that the subgenomic-length negative strands may be synthesized directly from the incoming genomic RNA, either by trans splicing of full-length negative strands or by transcription attenuation within the IG elements ( 3 , 22 , 23 , 30 ). (asm.org)
  • Moreover, the latter method is able to identify the dengue virus serotype by demonstrating defined sequence homologies in the viral genomic RNA. (asm.org)
  • We observed differential expression of approximately 500 annotated, long ncRNAs and 1,000 nonannotated genomic regions during infection. (asm.org)
  • RIG-I detects viral genomic RNA during negative-strand RNA virus infection. (ox.ac.uk)
  • Viral coat protein (CP), genomic RNA and fluorescently-labeled TGB2 were detected in plastid preparations isolated from the infected leaves, and viral RNA was localized to chloroplasts in infected tissues. (slu.se)
  • It has been shown that batai viruses from Japan, Malaysia and India share homologies in the genomic sequence more so than when virus strains from Europe and Asia are compared to each other. (wikipedia.org)
  • But these findings are also something researchers should keep in mind as they are designing new Zika virus vaccines and treatments that target the viral genome -- some approaches won't work unless they take methylation into account. (eurekalert.org)
  • Mouse hepatitis virus (MHV), a coronavirus in the Nidovirales order, contains a ∼32-kb linear, single-stranded, positive-polarity RNA genome ( 8 , 21 , 28 ). (asm.org)
  • The positive-strand mRNAs are arranged in a 3′ coterminal nested set, and each contains a 5′-end ∼72-nucleotide leader RNA sequence which is derived from the 5′ end of the genome ( 20 , 37 ). (asm.org)
  • Here, Alfalfa mosaic virus (AMV), a tripartite Alfamovirus, and transgenic Nicotiana tabacum plants expressing no (wild type), one (P2), or two (P12) viral genome segments were used to test whether the number of genome segments necessary for infection predicts the dose response. (upv.es)
  • Moreover, for P12 plants, the data support the IAH model, showing that the expression of virus genome segments by the host plant can modulate the infection kinetics of a tripartite virus to those of a monopartite virus. (upv.es)
  • Some of these may already have been present within the initial virus, and others may be coded for by the viral genome for production within the host cell. (thefreedictionary.com)
  • The genome sequence of Trichoplusia ni enables the use of this widespread lepidopteran pest as a model for both the study of small RNA pathways and insecticide resistance. (elifesciences.org)
  • Batai virus (BATV) is an enveloped, single-stranded, negative sense RNA genome. (wikipedia.org)
  • The positive-sense viral RNA genome can also serve as messenger RNA and can be translated into protein in the host cell. (wikipedia.org)
  • The genome of a positive-sense ssRNA virus usually contains relatively few genes, usually between three and ten, including an RdRP. (wikipedia.org)
  • For example, induction of type I interferon (IFN) in response to vesicular stomatitis virus (VSV) occurs independently of helicase and anti-HIV-1 activity [ 5 ]. (biochemj.org)
  • None of the cells were sensitive to infection by transmissible gastroenteritis virus (TGEV), a porcine coronavirus, or to infection mediated by the Spike (S) protein of SARS-coronavirus (SARS-CoV) incorporated into pseudotypes based on vesicular stomatitis virus (VSV). (edu.gh)
  • RIG-I, the most important RLR, recognizes a wide variety of RNA viruses, including influenza A virus (IAV), Sendai virus (SeV), respiratory syncytial virus (RSV), and vesicular stomatitis virus (VSV) ( 2 ). (sciencemag.org)
  • Leader RNA sequences are joined to body sequences of each subgenomic-length mRNA at highly conserved intergenic (IG) sites located just upstream from the coding sequences of each viral gene ( 7 , 14 , 27 , 32 ). (asm.org)
  • In trans , the free leader RNA binds with highly conserved internal IG elements in a full-length minus-strand template to prime transcription of each of the subgenomic mRNAs ( 1 , 3 , 6 , 19 , 25 ). (asm.org)
  • miRNAs are an abundant class of highly conserved small noncoding RNAs. (jimmunol.org)
  • Early viral replicative intermediates are detected by two recently characterized cystolic viral RNA receptors-RIG-I and MDA-5. (nih.gov)
  • While trans splicing is less attractive since full-length replicative intermediates (RIs) cannot be degraded into subgenomic-length RF RNA ( 3 , 30 ), the transcription attenuation model readily accounts for most of the observations central to coronavirus discontinuous transcription ( 30 ). (asm.org)
  • Proteolytic processing occurs in a highly regulated and coordinated manner with intermediates having distinct functions and playing important roles during viral infection. (nih.gov)
  • Further research will determine if cellular RNA helicases such as MOV10 represent suitable targets for the development of novel anti-IAV therapies. (biochemj.org)
  • Necrotizing soft-tissue infections (NSTIs) result in significant morbidity and mortality rates, with as many as 76% of patients dying during their index admission. (bioportfolio.com)
  • Curcumin inhibits an RNA Virus (EV71) in intestinal epithelial cells. (greenmedinfo.com)
  • Human cells modify viral RNA with m6A as a means to get rid of the infection. (eurekalert.org)
  • Cells can chemically modify RNA to influence protein production. (eurekalert.org)
  • To unravel the role of m6A in Zika virus infection of human cells growing in the laboratory, the researchers removed the human enzymes responsible for adding methyl groups to viral RNA. (eurekalert.org)
  • A) Serum starved cells were infected with 100 HA units of Sendai virus (SeV), 100 µg/ml poly-I:C or PMA treated (100 ng/ml) and RNA was isolated from cells at the times shown and optineurin mRNA levels determined by Q-PCR. (nih.gov)
  • Besides mRNAs, host cells also express a variety of noncoding RNAs, including small RNAs, that may also be subject to inhibition upon viral infection. (mdpi.com)
  • Mouse hepatitis virus (MHV)-infected cells contain full-length and subgenomic-length positive- and negative-strand RNAs. (asm.org)
  • In this report we demonstrate that the synthesis and molar ratios of subgenomic negative strands are similar in alternative host cells, suggesting that these RNAs function as important mediators of positive-strand synthesis. (asm.org)
  • In addition to the viral mRNAs, both full-length as well as subgenomic-length negative-strand RNAs and replicative form (RF) RNAs have been detected in porcine transmissible gastroenteritis virus-, bovine coronavirus-, and MHV-infected cells ( 13 , 30 , 32-35 ). (asm.org)
  • J. (2019) 476 , 467-provides insight regarding the mechanisms by which MOV10 restricts influenza A virus (IAV) infection in host cells. (biochemj.org)
  • 1. The concentration of uridine in the medium that allows maximum incorporation of isotopically-labelled uridine into RNA in CI5 cells was determined. (gla.ac.uk)
  • 5. Infection of exponentially-growing cells with pseudorabies virus caused a steady decrease (to 15% of the uninfected level) in incorporation of 3H uridine into RNA by 5 hours after infection. (gla.ac.uk)
  • It was found that in pseudorabies virus-infected cells, such a pulse-label produced radioactive low molecul8.r weight RM mainly of a size between 5S and 4S. (gla.ac.uk)
  • It was also shown that pre-tRNA from uninfected CI5 cells (pulse-labelled for 5-10 min) electrophoresed on 10% polyacrylamide gels as two peaks, analogous to peaks I and XI from the virus-infected cell, 7. (gla.ac.uk)
  • Alterations in level of methylation and nucleotide composition of 4S RNA after infection of "resting" cells were shown to be negligible. (gla.ac.uk)
  • 10. After infection of "resting" cells, it was found that ribosome-associated RNA synthesis did not seem to be further decreased. (gla.ac.uk)
  • However, non-protein-coding RNAs (ncRNAs) are transcribed in mammalian cells, and the roles of many of these ncRNAs remain enigmas. (asm.org)
  • Single Molecule Real Time (SMRT) sequencing was first applied and long-read sequencing analysis showed that a variety of H7N9 DI-RNA species were present in the patient samples and human bronchial epithelial cells. (flu.org.cn)
  • Taken together, we reveal the diversity and characteristics of DI-RNAs found in H7N9-infected patients, cells and animals. (flu.org.cn)
  • Similar to other molecular methods, however, identification of viral sequences in cells by HTS does not prove viral infection, since this could reflect carryover of inert viral sequences from reagents or other sources or the presence of transcriptionally inactive cellular sequences. (pasteur.fr)
  • In order to avoid the identification of inert viral sequences, we present a methodology based on metabolic RNA labeling and sequencing, which enables the specific identification of newly synthesized viral RNAs in infected cells, resulting in the ability to unambiguously distinguish active infection by DNA or RNA viruses from inert nucleic acids. (pasteur.fr)
  • Viral double-stranded RNA triggers Ig class switching by activating upper respiratory mucosa B cells through an innate TLR3 pathway involving BAFF. (semanticscholar.org)
  • Viruses induce high expression of BAFF by salivary gland epithelial cells through TLR- and type-I IFN-dependent and -independent pathways. (semanticscholar.org)
  • Here, we use three approaches to identify physiological RIG-I agonists in cells infected with influenza A virus or Sendai virus. (ox.ac.uk)
  • They discovered that cells lacking the exonuclease XRN1, mediator cellular RNA clearance, become resistant to SINV infection. (ox.ac.uk)
  • We are seeking to appoint a Postdoctoral Research Associate to elucidate, on a proteome-wide scale, the cellular players interplaying with viral RNA in infected cells. (castellolab.com)
  • We also reported that chicken MDA5 could interact with STING to construct a MDA5-STING-IFN-β pathway ( 17 ), which is not presence in mammalian cells, for RNA viruses recognition. (frontiersin.org)
  • This restriction is overcome when cells are co-infected with vaccinia virus (VACV), a vertebrate DNA virus. (scripps.edu)
  • This project will involve work with primary macrophages and epithelial cells and cell lines, basic molecular biology (cloning, RNA extraction, and qPCR, western blotting), confocal microscopy, and immunological techniques (ELISA, flow cytometry). (wemakescholars.com)
  • Although other reservoirs for HIV-1 exist, the general consensus among experts is that latent virus (HIV DNA in resting memory CD4+ T cells) is the primary barrier to HIV-1 eradication. (clinicaltrials.gov)
  • Fold change cell-associated HIV RNA in Total CD4 T-Cells. (clinicaltrials.gov)
  • CHIKV-3ʹ-Cre infection of tdTomato reporter mice resulted in a population of tdTomato + cells that persisted for at least 112 days. (docwirenews.com)
  • Treatment with an antibody against Mxra8, a recently defined host receptor for CHIKV, reduced the number of tdTomato + cells in the chronic phase and diminished the levels of chronic viral RNA, implicating these tdTomato + cells as the reservoir of chronic viral RNA. (docwirenews.com)
  • The approach followed here, based on using PPV chimeras in which an under-consideration RSS substitutes for HCPro, could further help to study the function of diverse RSSs in a 'highly sensitive' RNA-silencing context, such as that taking place in plant cells during the process of a viral infection. (microbiologyresearch.org)
  • The resistance to infection was overcome if cells were transfected to express the respective cellular receptor, porcine aminopeptidase N for TGEV or angiotensin-converting enzyme 2 for SARS-CoV. (edu.gh)
  • Notably, all cells were sensitive to infection by two paramyxoviruses (Sendai virus and bovine respiratory syncytial virus) and three influenza viruses from different subtypes. (edu.gh)
  • These results indicate that bat cells are more resistant to infection by coronaviruses than to infection by paramyxoviruses, filoviruses and influenza viruses. (edu.gh)
  • Furthermore, these results show a receptor-dependent restriction of the infection of bat cells by CoV. (edu.gh)
  • To better understand these processes we determined the changes in the host gene expression that occur during HCV infection of Huh-7.5 cells. (edu.pl)
  • These results indicate that VA RNA(I) plays a role in suppressing eIF-2α kinase activity during adenovirus infection of HeLa cells. (montclair.edu)
  • After the body fights the initial infection, the varicella zoster virus remains in nerve cells for the rest of a person's life. (medlineplus.gov)
  • that keep the virus from infecting other cells. (medlineplus.gov)
  • As people age, growth and division (proliferation) of T cells are diminished, reducing the immune system's ability to control the virus, which can allow its reactivation. (medlineplus.gov)
  • Health factors that impair T cells can also trigger reactivation of the varicella zoster virus. (medlineplus.gov)
  • Infection with human immunodeficiency virus (HIV), which infects and kills T cells, can also allow the virus to become active again. (medlineplus.gov)
  • It has therefore been assumed that susceptibility to HBV infection is restricted to differentiated cells. (pnas.org)
  • Cells were isolated from a liver tumor of a female patient suffering from hepatocarcinoma and hepatitis C infection. (pnas.org)
  • Because host cells do not have the ability to replicate "viral RNA" but are able to transcribe messenger RNA, RNA viruses must contain enzymes to produce genetic material for new virions. (thefreedictionary.com)
  • But no virus has the thousands of genes required by even the simplest cells. (thefreedictionary.com)
  • Some viruses do not produce rapid lysis of host cells, but rather remain latent for long periods in the host before the appearance of clinical symptoms. (thefreedictionary.com)
  • Our innate immune system and, in particular, the interferon response form the important first line of defence against these viruses. (mdpi.com)
  • ii) They had distinctive kinetic expression profiles in type I interferon receptor and STAT1 knockout mice during SARS-CoV infection, including unique signatures of ncRNA expression associated with lethal infection. (asm.org)
  • iii) Over 40% were similarly regulated in vitro in response to both influenza virus infection and interferon treatment. (asm.org)
  • The stimulator of interferon genes (STING) protein has been shown to play a pivotal role in response to both cytosolic RNA and dsDNA to elicit interferon (IFN) production in mammals. (frontiersin.org)
  • The success rates for interferon-based regimens improved from single digits in the 1970s to around 50% by 2002, accomplished by increasing dose, lengthening treatment, chemically stabilizing the interferon (by PEGylation) and adding ribavirin, an RNA-nucleoside analogue. (nature.com)
  • In late 2011, two NS3-4A protease inhibitors were approved for human use in combination with PEGylated interferon and ribavirin, raising treatment success to more than 70% for patients with HCV genotype 1 (there are six highly divergent and variable genotypes of the virus). (nature.com)
  • In consecutive serum samples from 25 tourists with acute dengue fever, virus-specific RNA was detected by using fully automated TaqMan reverse transcriptase PCR. (asm.org)
  • Patients with quantifiable HCV-RNA in serum were enrolled in the study. (biomedcentral.com)
  • HCV-RNA in saliva was associated with the level of serum viral load but not with periodontal or liver disease severity. (biomedcentral.com)
  • JEV RNA is rarely detected in serum or cerebrospinal fluid (CSF), and diagnosis of JEV infection is usually based on serological tests that are frequently difficult to interpret. (tropmedres.ac)
  • Unlike serum or CSF, urine is relatively easy to obtain, but, to date, there has been minimal work on the feasibility of testing urine for JEV RNA. (tropmedres.ac)
  • SummaryTo evaluate the concordance between viremia and antibody testing in hepatitis C virus (HCV) diagnosis, 682 serum or plasma samples collected from patients with known or suspected HCV infection were tested. (semanticscholar.org)
  • In this study, we examined the presence of WNV RNA in serum, plasma, whole-blood, CSF, and urine samples obtained from patients diagnosed with acute WNV infection during an outbreak which occurred in Israel in 2015. (cdc.gov)
  • CSF testing for immunoglobulin M (IgM) antibodies against West Nile virus (WNV) should be performed (in addition to testing of the patient's serum). (medscape.com)
  • Human +ssRNA viruses that currently have a large impact on public health include dengue virus (DENV) and the more recent (re-)emerging viruses such as chikungunya virus (CHIKV) and Zika virus (ZIKV) [ 1 ]. (mdpi.com)
  • Dengue virus RNA was found in almost all patients (17 of 18), if the samples had been taken soon after the onset of symptoms and before anti-dengue virus antibody had been produced. (asm.org)
  • RNA was detectable in only one of five persons who had anti-dengue virus immunoglobulin M (IgM) antibodies but not yet IgG antibodies. (asm.org)
  • In two early samples from two frequent travelers obtained 1 and 2 days after the onset of symptoms significant IgG antibody titers were present but there were no anti-dengue virus IgM antibodies. (asm.org)
  • 5 × 10 6 dengue virus RNA copies (dengue types 1 and 2) was detectable. (asm.org)
  • These findings of a high viral load in the presence of anti-dengue virus IgG antibody are suggestive of a secondary dengue virus infection. (asm.org)
  • In the 20 tourists (17 plus 1 plus 2) in whom viral RNA was found, the dengue virus serotype could be related to the area where the infection had taken place. (asm.org)
  • Most of our patients came from southeast Asia and most frequently had dengue virus type 1 infections (8 of 20). (asm.org)
  • Due to the vast expansion of air travelling new dengue virus strains may be introduced into a susceptible population in the tropics ( 20 , 21 ). (asm.org)
  • Both dengue virus-specific immunoglobulin G (IgG) and IgM antibodies are usually found in the sera from patients with acute primary infections, while the IgM response may be low or sometimes even absent in secondary dengue fever ( 27 ). (asm.org)
  • Therefore, the antibody response may be difficult to interpret with regard to an acute dengue fever, if other flavivirus infections cannot be excluded by clinical, laboratory, or epidemiological means. (asm.org)
  • Thus, information on the distribution of the four dengue virus serotypes and even of strains or quasispecies in tropical areas can be obtained ( 15 , 17 ). (asm.org)
  • Unfortunately, the technique of RT-PCR is handicapped both by time-consuming nested amplification protocols and by false positive reactions which may in part be due to the contamination of dengue virus DNA in the laboratory. (asm.org)
  • By using the TaqMan principle ( 8 , 11 , 13 ) the increase in dengue virus-specific DNA during amplification can be measured by simultaneously monitoring a fluorescence signal in the tightly sealed test tubes. (asm.org)
  • The vaccine is based on a live attenuated vaccine developed against dengue virus. (clinicaltrials.gov)
  • This study will evaluate the safety and immunogenicity of a live attenuated chimeric virus, WN/DEN4delta30, which is derived from the DEN4 dengue virus and wild-type WN serotypes. (clinicaltrials.gov)
  • Positive-sense RNA viruses account for a large fraction of known viruses, including many pathogens such as the hepatitis C virus, West Nile virus, dengue virus, and SARS and MERS coronaviruses, as well as less clinically serious pathogens such as the rhinoviruses that cause the common cold. (wikipedia.org)
  • In my lab's supportive environment, I have come to really appreciate microscopy, beautiful silver staining/Western blot gels, the satisfying popping sound in the homogenizing process of my RNA interactome capture whole cell lysates, and so much more! (castellolab.com)
  • The analyses of genes whose expression was decreased upon HCV infection showed that the latter were engaged in the metabolism of lipids and amino acids. (edu.pl)
  • Benedicto I, Molina-Jiménez F, Moreno-Otero R, López-Cabrera M, Majano PL (2011) Interplay among cellular polarization, lipoprotein metabolism and hepatitis C virus entry. (edu.pl)
  • The current diagnosis of West Nile virus (WNV) infection is primarily based on serology, since molecular identification of WNV RNA is unreliable due to the short viremia and absence of detectable virus in cerebrospinal fluid (CSF). (cdc.gov)
  • Our results demonstrate that 33 of 38 WNV patients had detectable WNV RNA in whole blood at the time of diagnosis, a higher rate than in any of the other sample types tested. (cdc.gov)
  • Success' for HCV treatment means no detectable virus 12 weeks after stopping treatment. (nature.com)
  • Although Middle East respiratory syndrome-coronavirus (MERS-CoV) does not infect large numbers of people like the afore-mentioned viruses, 35% of diagnosed patients die of MERS [ 2 ], and considering the virus' genetic possibilities, any change that increases transmissibility between humans would mean a serious public health threat that is considered worth preparing for. (mdpi.com)
  • In some cases, where these viruses were then efficiently transmitted between humans, they caused large disease outbreaks such as the 1918 flu pandemic or, more recently, outbreaks of Ebola and Coronavirus disease. (cdc.gov)
  • Online Cover This week features a Research Article that describes how distinct pathways stimulated by the related intracellular RNA receptors TLR7 and TLR8 promote virus-specific responses of human monocytes to RNA virus infection. (sciencemag.org)
  • Positive-sense ssRNA viruses belong to Group IV in the Baltimore classification. (wikipedia.org)
  • The (+)ssRNA viruses are classified into 3 orders - the Nidovirales, Picornavirales, and Tymovirales - and 33 families, of which 20 are not assigned to an order. (wikipedia.org)
  • Among known (+)ssRNA viruses, only the Leviviridae are bacteriophages (that is, viruses that infect bacteria). (wikipedia.org)
  • Positive-sense ssRNA viruses are the most common type of plant virus. (wikipedia.org)
  • Many pathogenic (+)ssRNA viruses are arthropod-borne viruses (also called arboviruses) - that is, transmitted by and capable of replicating in biting insects which then transfer the pathogen to animal hosts. (wikipedia.org)
  • Chikungunya virus (CHIKV) is an arthritogenic alphavirus that acutely causes fever as well as severe joint and muscle pain. (docwirenews.com)
  • Following primary transcription of the subgenomic mRNA, these mRNAs may act as templates for the synthesis of subgenomic-length negative strands containing antileader RNA ( 34 ). (asm.org)
  • in some viruses, such as poliovirus and rhinoviruses, normal protein synthesis is further disrupted by viral proteases degrading components required to initiate translation of cellular mRNA. (wikipedia.org)
  • Interestingly, modulation of particular viral infections appears to be dependent on different domains and/or functional properties of MOV10, such as helicase activity or association with cytoplasmic processing (P)-bodies. (biochemj.org)
  • 2. A 10% polyacrylamide gel electrophoresis system was calibrated and used to fractionate low molecular weight cytoplasmic RNA, excellent separation between 5S RNA and 4S RNA being obtained. (gla.ac.uk)
  • 5. In the uninfected, exponentially-growing CI5 cell, a pulse-label of 3H-uridine for a period of about 30-60 min produces cytoplasmic low molecular weight RNA in which almost all of the radioactivity is in 5S RNA and 4S RNA. (gla.ac.uk)
  • TuMV infection upregulates SUMO3 expression, and the sumoylation of NIb by SUMO3 regulates the nuclear-cytoplasmic partitioning of NIb. (gc.ca)
  • To further investigate the association of PMTV infection with chloroplasts, ultrastructural studies of thin sections of PMTV-infected potato and Nicotiana benthamiana leaves by electron microscopy revealed abnormal chloroplasts with cytoplasmic inclusions and terminal projections. (slu.se)