RNA Viruses: Viruses whose genetic material is RNA.RNA, Viral: Ribonucleic acid that makes up the genetic material of viruses.RNA Virus InfectionsRNA: 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)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, 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.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).DNA Viruses: Viruses whose nucleic acid is DNA.RNA Splicing: The ultimate exclusion of nonsense sequences or intervening sequences (introns) before the final RNA transcript is sent to the cytoplasm.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.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.Virus Assembly: The assembly of VIRAL STRUCTURAL PROTEINS and nucleic acid (VIRAL DNA or VIRAL RNA) to form a VIRUS PARTICLE.Virus Diseases: A general term for diseases produced by viruses.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.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.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).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.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.Viral Proteins: Proteins found in any species of virus.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)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.Measles virus: The type species of MORBILLIVIRUS and the cause of the highly infectious human disease MEASLES, which affects mostly children.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, Bacterial: Ribonucleic acid in bacteria having regulatory and catalytic roles as well as involvement in protein synthesis.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.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.Genome, Viral: The complete genetic complement contained in a DNA or RNA molecule in a virus.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.Genes, Viral: The functional hereditary units of VIRUSES.Cell Line: Established cell cultures that have the potential to propagate indefinitely.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.RNA Replicase: An enzyme that catalyses RNA-template-directed extension of the 3'- end of an RNA strand by one nucleotide at a time, and can initiate a chain de novo. (Enzyme Nomenclature, 1992, p293)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.RNA Helicases: A family of proteins that promote unwinding of RNA during splicing and translation.Nucleic Acid Conformation: The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.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.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.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.Virion: The infective system of a virus, composed of the viral genome, a protein core, and a protein coat called a capsid, which may be naked or enclosed in a lipoprotein envelope called the peplos.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.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.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.Mosaic Viruses: Viruses which produce a mottled appearance of the leaves of plants.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Capsid: The outer protein protective shell of a virus, which protects the viral nucleic acid.Antigens, Viral: Substances elaborated by viruses that have antigenic activity.Gene Expression Regulation, Viral: Any of the processes by which cytoplasmic factors influence the differential control of gene action in viruses.Oncogenic Viruses: Viruses that produce tumors.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.RNA, Catalytic: RNA that has catalytic activity. The catalytic RNA sequence folds to form a complex surface that can function as an enzyme in reactions with itself and other molecules. It may function even in the absence of protein. There are numerous examples of RNA species that are acted upon by catalytic RNA, however the scope of this enzyme class is not limited to a particular type of substrate.DNA, Viral: Deoxyribonucleic acid that makes up the genetic material of viruses.Virus Activation: The mechanism by which latent viruses, such as genetically transmitted tumor viruses (PROVIRUSES) or PROPHAGES of lysogenic bacteria, are induced to replicate and then released as infectious viruses. It may be effected by various endogenous and exogenous stimuli, including B-cell LIPOPOLYSACCHARIDES, glucocorticoid hormones, halogenated pyrimidines, IONIZING RADIATION, ultraviolet light, and superinfecting viruses.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Virus Latency: The ability of a pathogenic virus to lie dormant within a cell (latent infection). In eukaryotes, subsequent activation and viral replication is thought to be caused by extracellular stimulation of cellular transcription factors. Latency in bacteriophage is maintained by the expression of virally encoded repressors.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.Viral Plaque Assay: Method for measuring viral infectivity and multiplication in CULTURED CELLS. Clear lysed areas or plaques develop as the VIRAL PARTICLES are released from the infected cells during incubation. With some VIRUSES, the cells are killed by a cytopathic effect; with others, the infected cells are not killed but can be detected by their hemadsorptive ability. Sometimes the plaque cells contain VIRAL ANTIGENS which can be measured by IMMUNOFLUORESCENCE.RNA Polymerase II: A DNA-dependent RNA polymerase present in bacterial, plant, and animal cells. It functions in the nucleoplasmic structure and transcribes DNA into RNA. It has different requirements for cations and salt than RNA polymerase I and is strongly inhibited by alpha-amanitin. EC 2.7.7.6.Hemagglutinin Glycoproteins, Influenza Virus: Membrane glycoproteins from influenza viruses which are involved in hemagglutination, virus attachment, and envelope fusion. Fourteen distinct subtypes of HA glycoproteins and nine of NA glycoproteins have been identified from INFLUENZA A VIRUS; no subtypes have been identified for Influenza B or Influenza C viruses.RNA Caps: Nucleic acid structures found on the 5' end of eukaryotic cellular and viral messenger RNA and some heterogeneous nuclear RNAs. These structures, which are positively charged, protect the above specified RNAs at their termini against attack by phosphatases and other nucleases and promote mRNA function at the level of initiation of translation. Analogs of the RNA caps (RNA CAP ANALOGS), which lack the positive charge, inhibit the initiation of protein synthesis.RNA Folding: The processes of RNA tertiary structure formation.Semliki forest virus: A species of ALPHAVIRUS isolated in central, eastern, and southern Africa.Sendai virus: The type species of RESPIROVIRUS in the subfamily PARAMYXOVIRINAE. It is the murine version of HUMAN PARAINFLUENZA VIRUS 1, distinguished by host range.Viruses, Unclassified: Viruses whose taxonomic relationships have not been established.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.Parainfluenza Virus 1, Human: A species of RESPIROVIRUS also called hemadsorption virus 2 (HA2), which causes laryngotracheitis in humans, especially children.Mumps virus: The type species of RUBULAVIRUS that causes an acute infectious disease in humans, affecting mainly children. Transmission occurs by droplet infection.Capsid Proteins: Proteins that form the CAPSID of VIRUSES.Host-Pathogen Interactions: The interactions between a host and a pathogen, usually resulting in disease.Open Reading Frames: A sequence of successive nucleotide triplets that are read as CODONS specifying AMINO ACIDS and begin with an INITIATOR CODON and end with a stop codon (CODON, TERMINATOR).RNA Stability: The extent to which an RNA molecule retains its structural integrity and resists degradation by RNASE, and base-catalyzed HYDROLYSIS, under changing in vivo or in vitro conditions.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.Transcription, Genetic: The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.Simian immunodeficiency virus: Species of the genus LENTIVIRUS, subgenus primate immunodeficiency viruses (IMMUNODEFICIENCY VIRUSES, PRIMATE), that induces acquired immunodeficiency syndrome in monkeys and apes (SAIDS). The genetic organization of SIV is virtually identical to HIV.Tobacco Mosaic Virus: The type species of TOBAMOVIRUS which causes mosaic disease of tobacco. Transmission occurs by mechanical inoculation.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.HeLa Cells: The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.Sequence Analysis, RNA: A multistage process that includes cloning, physical mapping, subcloning, sequencing, and information analysis of an RNA SEQUENCE.Tombusvirus: A genus of plant viruses that infects ANGIOSPERMS. Transmission occurs mechanically and through soil, with one species transmitted via a fungal vector. The type species is Tomato bushy stunt virus.RNA Processing, Post-Transcriptional: Post-transcriptional biological modification of messenger, transfer, or ribosomal RNAs or their precursors. It includes cleavage, methylation, thiolation, isopentenylation, pseudouridine formation, conformational changes, and association with ribosomal protein.RNA, Fungal: Ribonucleic acid in fungi having regulatory and catalytic roles as well as involvement in protein synthesis.RNA, Antisense: RNA molecules which hybridize to complementary sequences in either RNA or DNA altering the function of the latter. Endogenous antisense RNAs function as regulators of gene expression by a variety of mechanisms. Synthetic antisense RNAs are used to effect the functioning of specific genes for investigative or therapeutic purposes.Recombination, Genetic: Production of new arrangements of DNA by various mechanisms such as assortment and segregation, CROSSING OVER; GENE CONVERSION; GENETIC TRANSFORMATION; GENETIC CONJUGATION; GENETIC TRANSDUCTION; or mixed infection of viruses.Bromovirus: A genus of tripartite plant viruses in the family BROMOVIRIDAE. Transmission is by beetles. Brome mosaic virus is the type species.Avian Sarcoma Viruses: Group of alpharetroviruses (ALPHARETROVIRUS) producing sarcomata and other tumors in chickens and other fowl and also in pigeons, ducks, and RATS.Viral Structural Proteins: Viral proteins that are components of the mature assembled VIRUS PARTICLES. They may include nucleocapsid core proteins (gag proteins), enzymes packaged within the virus particle (pol proteins), and membrane components (env proteins). These do not include the proteins encoded in the VIRAL GENOME that are produced in infected cells but which are not packaged in the mature virus particle,i.e. the so called non-structural proteins (VIRAL NONSTRUCTURAL PROTEINS).Hepatitis A virus: A species in the genus HEPATOVIRUS containing one serotype and two strains: HUMAN HEPATITIS A VIRUS and Simian hepatitis A virus causing hepatitis in humans (HEPATITIS A) and primates, respectively.RNA, Transfer: The small RNA molecules, 73-80 nucleotides long, that function during translation (TRANSLATION, GENETIC) to align AMINO ACIDS at the RIBOSOMES in a sequence determined by the mRNA (RNA, MESSENGER). There are about 30 different transfer RNAs. Each recognizes a specific CODON set on the mRNA through its own ANTICODON and as aminoacyl tRNAs (RNA, TRANSFER, AMINO ACYL), each carries a specific amino acid to the ribosome to add to the elongating peptide chains.Neutralization Tests: The measurement of infection-blocking titer of ANTISERA by testing a series of dilutions for a given virus-antiserum interaction end-point, which is generally the dilution at which tissue cultures inoculated with the serum-virus mixtures demonstrate cytopathology (CPE) or the dilution at which 50% of test animals injected with serum-virus mixtures show infectivity (ID50) or die (LD50).Totiviridae: A family of RNA viruses that infect fungi and protozoa. There are three genera: TOTIVIRUS; GIARDIAVIRUS; and LEISHMANIAVIRUS.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.Tobacco: A plant genus of the family SOLANACEAE. Members contain NICOTINE and other biologically active chemicals; its dried leaves are used for SMOKING.Virus Integration: Insertion of viral DNA into host-cell DNA. This includes integration of phage DNA into bacterial DNA; (LYSOGENY); to form a PROPHAGE or integration of retroviral DNA into cellular DNA to form a PROVIRUS.Genetic Vectors: DNA molecules capable of autonomous replication within a host cell and into which other DNA sequences can be inserted and thus amplified. Many are derived from PLASMIDS; BACTERIOPHAGES; or VIRUSES. They are used for transporting foreign genes into recipient cells. Genetic vectors possess a functional replicator site and contain GENETIC MARKERS to facilitate their selective recognition.Nodaviridae: A family of RNA viruses infecting insects and fish. There are two genera: Alphanodavirus and Betanodavirus.Avian leukosis virus: The type species of ALPHARETROVIRUS producing latent or manifest lymphoid leukosis in fowl.DNA Primers: Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.Foot-and-Mouth Disease Virus: The type species of APHTHOVIRUS, causing FOOT-AND-MOUTH DISEASE in cloven-hoofed animals. Several different serotypes exist.Protein Biosynthesis: The biosynthesis of PEPTIDES and PROTEINS on RIBOSOMES, directed by MESSENGER RNA, via TRANSFER RNA that is charged with standard proteinogenic AMINO ACIDS.Virus Attachment: The binding of virus particles to receptors on the host cell surface. For enveloped viruses, the virion ligand is usually a surface glycoprotein as is the cellular receptor. For non-enveloped viruses, the virus CAPSID serves as the ligand.BK Virus: A species of POLYOMAVIRUS apparently infecting over 90% of children but not clearly associated with any clinical illness in childhood. The virus remains latent in the body throughout life and can be reactivated under certain circumstances.Tumor Virus Infections: Infections produced by oncogenic viruses. The infections caused by DNA viruses are less numerous but more diverse than those caused by the RNA oncogenic viruses.Cytopathogenic Effect, Viral: Visible morphologic changes in cells infected with viruses. It includes shutdown of cellular RNA and protein synthesis, cell fusion, release of lysosomal enzymes, changes in cell membrane permeability, diffuse changes in intracellular structures, presence of viral inclusion bodies, and chromosomal aberrations. It excludes malignant transformation, which is CELL TRANSFORMATION, VIRAL. Viral cytopathogenic effects provide a valuable method for identifying and classifying the infecting viruses.Vesiculovirus: A genus of the family RHABDOVIRIDAE that infects a wide range of vertebrates and invertebrates. The type species is VESICULAR STOMATITIS INDIANA VIRUS.JC Virus: A species of POLYOMAVIRUS, originally isolated from the brain of a patient with progressive multifocal leukoencephalopathy. The patient's initials J.C. gave the virus its name. Infection is not accompanied by any apparent illness but serious demyelinating disease can appear later, probably following reactivation of latent virus.Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Orthomyxoviridae Infections: Virus diseases caused by the ORTHOMYXOVIRIDAE.Respiratory Syncytial Virus, Human: The type species of PNEUMOVIRUS and an important cause of lower respiratory disease in infants and young children. It frequently presents with bronchitis and bronchopneumonia and is further characterized by fever, cough, dyspnea, wheezing, and pallor.Bluetongue virus: The type species of ORBIVIRUS causing a serious disease in sheep, especially lambs. It may also infect wild ruminants and other domestic animals.Moloney murine leukemia virus: A strain of Murine leukemia virus (LEUKEMIA VIRUS, MURINE) arising during the propagation of S37 mouse sarcoma, and causing lymphoid leukemia in mice. It also infects rats and newborn hamsters. It is apparently transmitted to embryos in utero and to newborns through mother's milk.RNA Precursors: RNA transcripts of the DNA that are in some unfinished stage of post-transcriptional processing (RNA PROCESSING, POST-TRANSCRIPTIONAL) required for function. RNA precursors may undergo several steps of RNA SPLICING during which the phosphodiester bonds at exon-intron boundaries are cleaved and the introns are excised. Consequently a new bond is formed between the ends of the exons. Resulting mature RNAs can then be used; for example, mature mRNA (RNA, MESSENGER) is used as a template for protein production.DNA Virus InfectionsVirus Physiological Phenomena: Biological properties, processes, and activities of VIRUSES.RNA, Small Nuclear: Short chains of RNA (100-300 nucleotides long) that are abundant in the nucleus and usually complexed with proteins in snRNPs (RIBONUCLEOPROTEINS, SMALL NUCLEAR). Many function in the processing of messenger RNA precursors. Others, the snoRNAs (RNA, SMALL NUCLEOLAR), are involved with the processing of ribosomal RNA precursors.Evolution, Molecular: The process of cumulative change at the level of DNA; RNA; and PROTEINS, over successive generations.Parainfluenza Virus 3, Human: A species of RESPIROVIRUS frequently isolated from small children with pharyngitis, bronchitis, and pneumonia.Reverse Transcriptase Polymerase Chain Reaction: A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.Plasmids: Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.RNA, Untranslated: RNA which does not code for protein but has some enzymatic, structural or regulatory function. Although ribosomal RNA (RNA, RIBOSOMAL) and transfer RNA (RNA, TRANSFER) are also untranslated RNAs they are not included in this scope.Simplexvirus: A genus of the family HERPESVIRIDAE, subfamily ALPHAHERPESVIRINAE, consisting of herpes simplex-like viruses. The type species is HERPESVIRUS 1, HUMAN.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.Bunyamwera virus: A species in the ORTHOBUNYAVIRUS genus of the family BUNYAVIRIDAE. A large number of serotypes or strains exist in many parts of the world. They are transmitted by mosquitoes and infect humans in some areas.Porcine respiratory and reproductive syndrome virus: A species of ARTERIVIRUS causing reproductive and respiratory disease in pigs. The European strain is called Lelystad virus. Airborne transmission is common.Diarrhea Viruses, Bovine Viral: A group of viruses in the genus PESTIVIRUS, causing diarrhea, fever, oral ulcerations, hemorrhagic syndrome, and various necrotic lesions among cattle and other domestic animals. The two species (genotypes), BVDV-1 and BVDV-2 , exhibit antigenic and pathological differences. The historical designation, BVDV, consisted of both (then unrecognized) genotypes.RNA, Plant: Ribonucleic acid in plants having regulatory and catalytic roles as well as involvement in protein synthesis.Virulence: The degree of pathogenicity within a group or species of microorganisms or viruses as indicated by case fatality rates and/or the ability of the organism to invade the tissues of the host. The pathogenic capacity of an organism is determined by its VIRULENCE FACTORS.Hepatitis E virus: A positive-stranded RNA virus species in the genus HEPEVIRUS, causing enterically-transmitted non-A, non-B hepatitis (HEPATITIS E).Virology: The study of the structure, growth, function, genetics, and reproduction of viruses, and VIRUS DISEASES.Transfection: The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.Arteritis Virus, Equine: The type species of the genus ARTERIVIRUS and the etiologic agent of an important equine respiratory disease causing abortion, pneumonia, or other infections.Nucleic Acid Hybridization: Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)Yellow fever virus: The type species of the FLAVIVIRUS genus. Principal vector transmission to humans is by AEDES spp. mosquitoes.Bacteriophage phi 6: Virulent bacteriophage and sole member of the genus Cystovirus that infects Pseudomonas species. The virion has a segmented genome consisting of three pieces of doubled-stranded DNA and also a unique lipid-containing envelope.Species Specificity: The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.Plant Diseases: Diseases of plants.RNA-Binding Proteins: Proteins that bind to RNA molecules. Included here are RIBONUCLEOPROTEINS and other proteins whose function is to bind specifically to RNA.Leukemia Virus, Feline: A species of GAMMARETROVIRUS causing leukemia, lymphosarcoma, immune deficiency, or other degenerative diseases in cats. Several cellular oncogenes confer on FeLV the ability to induce sarcomas (see also SARCOMA VIRUSES, FELINE).Virus Inactivation: Inactivation of viruses by non-immune related techniques. They include extremes of pH, HEAT treatment, ultraviolet radiation, IONIZING RADIATION; DESICCATION; ANTISEPTICS; DISINFECTANTS; organic solvents, and DETERGENTS.Retroviridae: Family of RNA viruses that infects birds and mammals and encodes the enzyme reverse transcriptase. The family contains seven genera: DELTARETROVIRUS; LENTIVIRUS; RETROVIRUSES TYPE B, MAMMALIAN; ALPHARETROVIRUS; GAMMARETROVIRUS; RETROVIRUSES TYPE D; and SPUMAVIRUS. A key feature of retrovirus biology is the synthesis of a DNA copy of the genome which is integrated into cellular DNA. After integration it is sometimes not expressed but maintained in a latent state (PROVIRUSES).RNA-Directed DNA Polymerase: An enzyme that synthesizes DNA on an RNA template. It is encoded by the pol gene of retroviruses and by certain retrovirus-like elements. EC 2.7.7.49.Rhabdoviridae: A family of bullet-shaped viruses of the order MONONEGAVIRALES, infecting vertebrates, arthropods, protozoa, and plants. Genera include VESICULOVIRUS; LYSSAVIRUS; EPHEMEROVIRUS; NOVIRHABDOVIRUS; Cytorhabdovirus; and Nucleorhabdovirus.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.RNA, Satellite: Small, linear single-stranded RNA molecules functionally acting as molecular parasites of certain RNA plant viruses. Satellite RNAs exhibit four characteristic traits: (1) they require helper viruses to replicate; (2) they are unnecessary for the replication of helper viruses; (3) they are encapsidated in the coat protein of the helper virus; (4) they have no extensive sequence homology to the helper virus. Thus they differ from SATELLITE VIRUSES which encode their own coat protein, and from the genomic RNA; (=RNA, VIRAL); of satellite viruses. (From Maramorosch, Viroids and Satellites, 1991, p143)Myxoma virus: The type species of LEPORIPOXVIRUS causing infectious myxomatosis, a severe generalized disease, in rabbits. Tumors are not always present.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.Influenza, Human: An acute viral infection in humans involving the respiratory tract. It is marked by inflammation of the NASAL MUCOSA; the PHARYNX; and conjunctiva, and by headache and severe, often generalized, myalgia.Cowpox virus: A species of ORTHOPOXVIRUS that is the etiologic agent of COWPOX. It is closely related to but antigenically different from VACCINIA VIRUS.Archaeal Viruses: Viruses whose hosts are in the domain ARCHAEA.Lassa virus: A species of ARENAVIRUS, part of the Old World Arenaviruses (ARENAVIRUSES, OLD WORLD), and the etiologic agent of LASSA FEVER. LASSA VIRUS is a common infective agent in humans in West Africa. Its natural host is the multimammate mouse Mastomys natalensis.Satellite Viruses: Defective viruses which can multiply only by association with a helper virus which complements the defective gene. Satellite viruses may be associated with certain plant viruses, animal viruses, or bacteriophages. They differ from satellite RNA; (RNA, SATELLITE) in that satellite viruses encode their own coat protein.Variola virus: A species of ORTHOPOXVIRUS causing infections in humans. No infections have been reported since 1977 and the virus is now believed to be virtually extinct.Viral Core Proteins: Proteins found mainly in icosahedral DNA and RNA viruses. They consist of proteins directly associated with the nucleic acid inside the NUCLEOCAPSID.Norwalk virus: The type species in the genus NOROVIRUS, first isolated in 1968 from the stools of school children in Norwalk, Ohio, who were suffering from GASTROENTERITIS. The virions are non-enveloped spherical particles containing a single protein. Multiple strains are named after the places where outbreaks have occurred.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Chikungunya virus: A species of ALPHAVIRUS causing an acute dengue-like fever.Picornaviridae: A family of small RNA viruses comprising some important pathogens of humans and animals. Transmission usually occurs mechanically. There are nine genera: APHTHOVIRUS; CARDIOVIRUS; ENTEROVIRUS; ERBOVIRUS; HEPATOVIRUS; KOBUVIRUS; PARECHOVIRUS; RHINOVIRUS; and TESCHOVIRUS.HIV-1: The type species of LENTIVIRUS and the etiologic agent of AIDS. It is characterized by its cytopathic effect and affinity for the T4-lymphocyte.Serial Passage: Inoculation of a series of animals or in vitro tissue with an infectious bacterium or virus, as in VIRULENCE studies and the development of vaccines.Encephalitis Viruses: A collection of single-stranded RNA viruses scattered across the Bunyaviridae, Flaviviridae, and Togaviridae families whose common property is the ability to induce encephalitic conditions in infected hosts.Nucleocapsid Proteins: Viral proteins found in either the NUCLEOCAPSID or the viral core (VIRAL CORE PROTEINS).Viral Load: The quantity of measurable virus in a body fluid. Change in viral load, measured in plasma, is sometimes used as a SURROGATE MARKER in disease progression.Potyvirus: A large genus of plant viruses of the family POTYVIRIDAE which infect mainly plants of the Solanaceae. Transmission is primarily by aphids in a non-persistent manner. The type species is potato virus Y.Antibodies, Viral: Immunoglobulins produced in response to VIRAL ANTIGENS.Herpesvirus 1, Human: The type species of SIMPLEXVIRUS causing most forms of non-genital herpes simplex in humans. Primary infection occurs mainly in infants and young children and then the virus becomes latent in the dorsal root ganglion. It then is periodically reactivated throughout life causing mostly benign conditions.Hepatitis Delta Virus: A defective virus, containing particles of RNA nucleoprotein in virion-like form, present in patients with acute hepatitis B and chronic hepatitis. It requires the presence of a hepadnavirus for full replication. This is the lone species in the genus Deltavirus.Herpesvirus 4, Human: The type species of LYMPHOCRYPTOVIRUS, subfamily GAMMAHERPESVIRINAE, infecting B-cells in humans. It is thought to be the causative agent of INFECTIOUS MONONUCLEOSIS and is strongly associated with oral hairy leukoplakia (LEUKOPLAKIA, HAIRY;), BURKITT LYMPHOMA; and other malignancies.Sequence Alignment: The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.Epstein-Barr Virus Infections: Infection with human herpesvirus 4 (HERPESVIRUS 4, HUMAN); which may facilitate the development of various lymphoproliferative disorders. These include BURKITT LYMPHOMA (African type), INFECTIOUS MONONUCLEOSIS, and oral hairy leukoplakia (LEUKOPLAKIA, HAIRY).Haplorhini: A suborder of PRIMATES consisting of six families: CEBIDAE (some New World monkeys), ATELIDAE (some New World monkeys), CERCOPITHECIDAE (Old World monkeys), HYLOBATIDAE (gibbons and siamangs), CALLITRICHINAE (marmosets and tamarins), and HOMINIDAE (humans and great apes).Genetic Variation: Genotypic differences observed among individuals in a population.Encephalitis Viruses, Tick-Borne: A subgroup of the genus FLAVIVIRUS that causes encephalitis and hemorrhagic fevers and is found in eastern and western Europe and the former Soviet Union. It is transmitted by TICKS and there is an associated milk-borne transmission from viremic cattle, goats, and sheep.Nucleocapsid: A protein-nucleic acid complex which forms part or all of a virion. It consists of a CAPSID plus enclosed nucleic acid. Depending on the virus, the nucleocapsid may correspond to a naked core or be surrounded by a membranous envelope.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Tombusviridae: A family of RNA plant viruses infecting dicotyledons. Transmission is mainly by mechanical inoculation and through propagative plant material. All species elicit formation of multivesicular inclusion bodies. There are at least eight genera: Aureusvirus, Avenavirus, CARMOVIRUS, Dianthovirus, Machlomovirus, Necrovirus, Panicovirus, and TOMBUSVIRUS.Sequence Homology, Nucleic Acid: The sequential correspondence of nucleotides in one nucleic acid molecule with those of another nucleic acid molecule. Sequence homology is an indication of the genetic relatedness of different organisms and gene function.HIV Infections: Includes the spectrum of human immunodeficiency virus infections that range from asymptomatic seropositivity, thru AIDS-related complex (ARC), to acquired immunodeficiency syndrome (AIDS).Carmovirus: A genus in the family TOMBUSVIRIDAE mostly found in temperate regions. Some species infecting legumes (FABACEAE) are reported from tropical areas. Most viruses are soil-borne, but some are transmitted by the fungus Olpidium radicale and others by beetles. Carnation mottle virus is the type species.Recombinant Proteins: Proteins prepared by recombinant DNA technology.RNA, Neoplasm: RNA present in neoplastic tissue.RNA, Protozoan: Ribonucleic acid in protozoa having regulatory and catalytic roles as well as involvement in protein synthesis.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Rift Valley fever virus: A mosquito-borne species of the PHLEBOVIRUS genus found in eastern, central, and southern Africa, producing massive hepatitis, abortion, and death in sheep, goats, cattle, and other animals. It also has caused disease in humans.Viral Interference: A phenomenon in which infection by a first virus results in resistance of cells or tissues to infection by a second, unrelated virus.Hepatitis C: INFLAMMATION of the LIVER in humans caused by HEPATITIS C VIRUS, a single-stranded RNA virus. Its incubation period is 30-90 days. Hepatitis C is transmitted primarily by contaminated blood parenterally, and is often associated with transfusion and intravenous drug abuse. However, in a significant number of cases, the source of hepatitis C infection is unknown.Promoter Regions, Genetic: DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes.Hemagglutinins, Viral: Specific hemagglutinin subtypes encoded by VIRUSES.5' Untranslated Regions: The sequence at the 5' end of the messenger RNA that does not code for product. This sequence contains the ribosome binding site and other transcription and translation regulating sequences.Reoviridae: A family of unenveloped RNA viruses with cubic symmetry. The twelve genera include ORTHOREOVIRUS; ORBIVIRUS; COLTIVIRUS; ROTAVIRUS; Aquareovirus, Cypovirus, Phytoreovirus, Fijivirus, Seadornavirus, Idnoreovirus, Mycoreovirus, and Oryzavirus.Respirovirus: A genus of the family PARAMYXOVIRIDAE (subfamily PARAMYXOVIRINAE) where all the virions have both HEMAGGLUTININ and NEURAMINIDASE activities and encode a non-structural C protein. SENDAI VIRUS is the type species.Templates, Genetic: Macromolecular molds for the synthesis of complementary macromolecules, as in DNA REPLICATION; GENETIC TRANSCRIPTION of DNA to RNA, and GENETIC TRANSLATION of RNA into POLYPEPTIDES.Lymphocytic choriomeningitis virus: The type species of ARENAVIRUS, part of the Old World Arenaviruses (ARENAVIRUSES, OLD WORLD), producing a silent infection in house and laboratory mice. In humans, infection with LCMV can be inapparent, or can present with an influenza-like illness, a benign aseptic meningitis, or a severe meningoencephalomyelitis. The virus can also infect monkeys, dogs, field mice, guinea pigs, and hamsters, the latter an epidemiologically important host.Ribonucleases: Enzymes that catalyze the hydrolysis of ester bonds within RNA. EC 3.1.-.Hepatitis Viruses: Any of the viruses that cause inflammation of the liver. They include both DNA and RNA viruses as well viruses from humans and animals.Microscopy, Electron: Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.Cell Transformation, Viral: An inheritable change in cells manifested by changes in cell division and growth and alterations in cell surface properties. It is induced by infection with a transforming virus.Kinetics: The rate dynamics in chemical or physical systems.SARS Virus: A species of CORONAVIRUS causing atypical respiratory disease (SEVERE ACUTE RESPIRATORY SYNDROME) in humans. The organism is believed to have first emerged in Guangdong Province, China, in 2002. The natural host is the Chinese horseshoe bat, RHINOLOPHUS sinicus.

Inhibition of Pichinde virus replication by actinomycin D. (1/1788)

The yields of Pichinde virus, a member of the arenavirus group, were markedly inhibited when infected BHK 21 cells were incubated in the presence of 0.4 to 4 mug/ml of actinomycin D. Maximal inhibition was observed when actinomycin D was added after the adsorption of virus to cultures; however, addition of drug as late as 12 h after infection reduced the 24 h yield by 50%. Virus antigen synthesis, as measured by complement fixation and immunodiffusion, was not dramatically reduced by actinomycin D. The expression of virus antigens on the surface of infected cells was greater on cells treated with actinomycin D than on untreated cells. Putative defective particles with a density of Pichinde virus were not detected in fluids of cultures incubated with actinomycin D and 3H-amino acids. Actinomycin D appears to inhibit Pichinde virus late in the replicative cycle. The observations raise the possibility that the drug inhibits the synthesis of proteins of the host cell membrane which are required for virus maturation.  (+info)

Transmission bottlenecks as determinants of virulence in rapidly evolving pathogens. (2/1788)

Transmission bottlenecks occur in pathogen populations when only a few individual pathogens are transmitted from one infected host to another in the initiation of a new infection. Transmission bottlenecks can dramatically affect the evolution of virulence in rapidly evolving pathogens such as RNA viruses. Characterizing pathogen diversity with the quasispecies concept, we use analytical and simulation methods to demonstrate that severe bottlenecks are likely to drive down the virulence of a pathogen because of stochastic loss of the most virulent pathotypes, through a process analogous to Muller's ratchet. We investigate in this process the roles of host population size, duration of within-host viral replication, and transmission bottleneck size. We argue that the patterns of accumulation of deleterious mutation may explain differing levels of virulence in vertically and horizontally transmitted diseases.  (+info)

Sequence of the genomic RNA of nudaurelia beta virus (Tetraviridae) defines a novel virus genome organization. (3/1788)

The monopartite genome of Nudaurelia beta virus, the type species of the Betatetravirus genus of the family Tetraviridae, consists of a single-stranded positive-sense RNA (ss+RNA) of 6625 nucleotides containing two open reading frames (ORFs). The 5' proximal ORF of 5778 nucleotides encodes a protein of 215 kDa containing three functional domains characteristic of RNA-dependent RNA polymerases of ss+RNA viruses. The 3' proximal ORF of 1836 nucleotides, which encodes the 66-kDa capsid precursor protein, overlaps the replicase gene by more than 99% (1827 nucleotides) and is in the +1 reading frame relative to the replicase reading frame. This capsid precursor is expressed via a 2656-nucleotide subgenomic RNA. The 3' terminus of the genome can be folded into a tRNA-like secondary structure that has a valine anticodon; the tRNA-like structure lacks a pseudoknot in the aminoacyl stem, a feature common to both genera of tetraviruses. Comparison of the sequences of Nudaurelia beta virus and another member of the Tetraviridae, Helicoverpa armigera stunt virus, which is in the genus Omegatetravirus, shows identities of 31.6% for the replicase and 24.5% for the capsid protein. The viruses in the genera Betatetravirus and Omegatetravirus of the Tetraviridae are clearly related but show significant differences in their genome organization. It is concluded that the ancestral virus with a bipartite genome, as found in the genus Omegatetravirus, likely evolved from a virus with an unsegmented genome, as found in the genus Betatetravirus, through evolution of the subgenomic RNA into a separate genomic component, with the accompanying loss of the capsid gene from the longer genomic RNA.  (+info)

Multiple mitochondrial viruses in an isolate of the Dutch Elm disease fungus Ophiostoma novo-ulmi. (4/1788)

The nucleotide sequences of three mitochondrial virus double-stranded (ds) RNAs, RNA-4 (2599 nucleotides), RNA-5 (2474 nucleotides), and RNA-6 (2343 nucleotides), in a diseased isolate Log1/3-8d2 (Ld) of the Dutch elm disease fungus Ophiostoma novo-ulmi have been determined. All these RNAs are A-U-rich (71-73% A + U residues). Using the fungal mitochondrial genetic code in which UGA codes for tryptophan, the positive-strand of each of RNAs 4, 5, and 6 contains a single open reading frame (ORF) with the potential to encode a protein of 783, 729, and 695 amino acids, respectively, all of which contain conserved motifs characteristic of RNA-dependent RNA polymerases (RdRps). Sequence comparisons showed that these RNAs are related to each other and to a previously characterized RNA, RNA-3a, from the same O. novo-ulmi isolate, especially within the RdRp-like motifs. However, the overall RNA nucleotide and RdRp amino acid sequence identities were relatively low (43-55% and 20-32%, respectively). The 5'- and 3'-terminal sequences of these RNAs are different, but they can all be folded into potentially stable stem-loop structures. Those of RNA-4 and RNA-6 have inverted complementarity, potentially forming panhandle structures. Their molecular and biological properties indicate that RNAs 3a, 4, 5, and 6 are the genomes of four different viruses, which replicate independently in the same cell. These four viruses are also related to a mitochondrial RNA virus from another fungus, Cryphonectria parasitica, recently designated the type species of the Mitovirus genus of the Narnaviridae family, and to a virus from the fungus Rhizoctonia solani. It is proposed that the four O. novo-ulmi mitochondrial viruses are assigned to the Mitovirus genus and designated O. novo-ulmi mitovirus (OnuMV) 3a-Ld, 4-Ld, 5-Ld, and 6-Ld, respectively. Northern blot analysis indicated that O. novo-ulmi Ld nucleic acid extracts contain more single-stranded (ss, positive-stranded) RNA than dsRNA for all three newly described mitoviruses. O. novo-ulmi RNA-7, previously believed to be a satellite-like RNA, is shown to be a defective RNA, derived from OnuMV4-Ld RNA by multiple internal deletions. OnuMV4-Ld is therefore the helper virus for the replication of both RNA-7 and another defective RNA, RNA-10. Sequence comparisons indicate that RNA-10 could be derived from RNA-7, as previously suggested, or derived directly from RNA-4.  (+info)

Comparative study of viral encephalopathy and retinopathy in juvenile sea bass Dicentrarchus labrax infected in different ways. (5/1788)

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)

Structural constraints on RNA virus evolution. (6/1788)

The recently discovered hepatitis G virus (HGV) or GB virus C (GBV-C) is widely distributed in human populations, and homologues such as HGV/GBV-CCPZ and GBV-A are found in a variety of different primate species. Both epidemiological and phylogenetic analyses support the hypothesis that GB viruses coevolved with their primate hosts, although their degree of sequence similarity appears incompatible with the high rate of sequence change of HGV/GBV-C over short observation periods. Comparison of complete coding sequences (8,500 bases) of different genotypes of HGV/GBV-C showed an excess of invariant synonymous sites (at 23% of all codons) compared with the frequency expected by chance (10%). To investigate the hypothesis that RNA secondary-structure formation through internal base pairing limited sequence variability at these sites, an algorithm was developed to detect covariant sites among HGV/GBV-C sequences of different genotypes. At least 35 covariant sites that were spatially associated with potential stem-loop structures were detected, whose positions correlated with positions in the genome that showed reductions in synonymous variability. Although the functional roles of the predicted secondary structures remain unclear, the restriction of sequence change imposed by secondary-structure formation provides a mechanism for differences in net rate of accumulation of nucleotide substitutions at different sites. However, the resulting disparity between short- and long-term rates of sequence change of HGV/GBV-C violates the assumptions of the "molecular clock." This places a major restriction on the use of nucleotide or amino acid sequence comparisons to calculate times of divergence of other viruses evolving under the same structural constraints as GB viruses.  (+info)

A highly membrane-active peptide in Flock House virus: implications for the mechanism of nodavirus infection. (7/1788)

BACKGROUND: Nodaviruses are among the simplest animal viruses, and are therefore attractive systems for deconvoluting core viral processes such as assembly, infection and uncoating. Membrane translocation of the single-stranded RNA genome of nodaviruses has been proposed to be mediated by direct lipid-protein interactions between a post-assembly autocatalytic cleavage product from the capsomere and the target membrane. To probe the validity of this hypothesis, we have synthesized a 21-residue Met-->Nle (norleucine) variant of the amino-terminal helical domain (denoted here as gamma1) of the cleavage peptide in Flock House nodavirus (FHV) and studied its ability to alter membrane structure and function. RESULTS: The synthetic peptide gamma1 increases membrane permeability to hydrophilic solutes, as judged by fluorescence experiments with liposome-encapsulated dyes and ion-conductance measurements. Furthermore, peptide orientation and location within lipid bilayers was determined using tryptophan-fluorescence-quenching experiments and attenuated total reflectance infrared spectroscopy. CONCLUSIONS: The helical domain of the FHV cleavage product partitions spontaneously into lipid bilayers and increases membrane permeability, consistent with the postulated mechanism for viral genome translocation. The existence of a membrane-binding domain in the FHV cleavage sequence suggests peptide-triggered disruption of the endosomal membrane as a prelude to viral uncoating in the host cytoplasm. A model for this interaction is proposed.  (+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. (8/1788)

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)

*Plant virus

Some viruses (e.g. tobacco mosaic virus (TMV)) have RNA sequences that contain a "leaky" stop codon. In TMV 95% of the time the ... Plant viruses are viruses that affect plants. Like all other viruses, plant viruses are obligate intracellular parasites that ... 75% of plant viruses have genomes that consist of single stranded RNA (ssRNA). 65% of plant viruses have +ssRNA, meaning that ... The first virus to be discovered (see below) was Tobacco mosaic virus (TMV). This and other viruses cause an estimated US$60 ...

*Negative-sense single-stranded RNA virus

The virus uses its own RNA replicase, also known as RNA-dependent RNA polymerase (RdRp), to form positive RNA template strands ... A negative-sense single-stranded RNA virus (or (-)ssRNA virus) is a virus that uses negative sense, single-stranded RNA as its ... Negative sense ssRNA viruses need RNA polymerase to form a positive sense RNA. The positive-sense RNA acts as a viral mRNA, ... Positive-sense single-stranded RNA virus Double-stranded RNA virus Baltimore classification Sense (molecular biology) Baltimore ...

*Nudivirus

Unassigned Viruses. In: Virus Taxonomy: The Sixth Report of the International Committee on Taxonomy of Viruses. Springer-Verlag ... The 20 cores genes common in both Baculovirus and Nudivirus are involved in RNA transcription, DNA replication, virion ... The virus genome, in proviral form, is integrated on wasp genome. However, the viruses are not embedded in inclusion bodies ( ... So, the full genome of the virus is integrated into the genome of the wasp and the virus only replicates in specific cells in ...

*Mycovirus

... as both types of RNA viruses infect bacteria as well as eukaryotes. Although the origin of viruses is still not well understood ... According to Koonin, RNA viruses colonized eukaryotes first and subsequently co-evolved with their hosts. This concept fits ... Furthermore, the recent discovery of an ssDNA mycovirus tempted some researchers to suggest that RNA and DNA viruses might have ... However, many virus families containing mycoviruses have only sparsely been sampled. Mycovirology is the study of viruses ...

*DNA-directed RNA interference

"Use of RNA interference to modulate liver adenoma development in a murine model transgenic for hepatitis B virus". Gene Therapy ... Any RNA, including endogenous mRNAs or viral RNAs, can be silenced by designing constructs to express double-stranded RNA ... DNA constructs are designed to express self-complementary double-stranded RNAs, typically short-hairpin RNAs (shRNA), that once ... DNA-directed RNA interference (ddRNAi) is a gene-silencing technique that utilizes DNA constructs to activate an animal cell's ...

*Positive-sense single-stranded RNA virus

A positive-sense single-stranded RNA virus (or (+)ssRNA virus) is a virus that uses positive sense, single-stranded RNA as its ... All positive-sense ssRNA virus genomes encode RNA-dependent RNA polymerase (RdRP), a viral protein that synthesizes RNA from an ... Negative-sense single-stranded RNA virus Double-stranded RNA virus Baltimore classification Sense (molecular biology) Baltimore ... Single stranded RNA viruses are classified as positive or negative depending on the sense or polarity of the RNA. The positive- ...

*RNA virus

... virus Extra small virus Jingmen tick virus Le Blanc virus Nesidiocoris tenuis virus 1 Nylanderia fulva virus 1 Orsay virus ... The majority of fungal viruses are double-stranded RNA viruses. A small number of positive-strand RNA viruses have been ... each virion can be transcribed to several positive-sense RNAs. Ambisense RNA viruses resemble negative-sense RNA viruses, ... includes Yellow fever virus, West Nile virus, Hepatitis C virus, Dengue fever virus, Zika virus Family Fusariviridae Family ...

*Double-stranded RNA viruses

Microbiology Virology RNA virus Virus classification List of viruses Animal virology Patton 2008 Ghabrial SA (1998). "Origin, ... 2008). "The Yeast dsRNA Virus L-A Resembles Mammalian dsRNA Virus Cores". Segmented Double-stranded RNA Viruses: Structure and ... Double-stranded (ds) RNA viruses are a diverse group of viruses that vary widely in host range (humans, animals, plants, fungi ... The virus-encoded RNA-dependent RNA polymerase, VP1, is incorporated into the capsid through its association with VP3. VP3 also ...

*Bovine leukaemia virus RNA packaging signal

... primary nucleotide sequence of the bovine leukemia virus RNA packaging signal can influence efficient RNA packaging and virus ... This family represents the bovine leukaemia virus RNA encapsidation (packaging) signal, which is essential for efficient viral ... Mansky, LM; Wisniewski, RM (April 1998). "The bovine leukemia virus encapsidation signal is composed of RNA secondary ... The RNA encapsidation (packaging) signal participates in the process of RNA packaging and aids in making viral packaging and ...

*Alfalfa mosaic virus RNA 1 5' UTR stem-loop

RNA Vlot, AC; Bol JF (2003). "The 5′ Untranslated Region of Alfalfa Mosaic Virus RNA 1 Is Involved in Negative-Strand RNA ... The Alfalfa mosaic virus RNA 1 5' UTR stem-loop represents a putative stem-loop structure found in the 5' UTR in RNA 1 of ... This family is required for negative strand RNA synthesis in the alfalfa mosaic virus and may also be involved in positive ... Page for Alfalfa mosaic virus RNA 1 5' UTR stem-loop at Rfam. ... alfalfa mosaic virus. RNA 1 is responsible for encoding the ...

*Infectious bronchitis virus D-RNA

The Infectious bronchitis virus D-RNA is an RNA element known as defective RNA or D-RNA. This element is thought to be ... "Utilizing fowlpox virus recombinants to generate defective RNAs of the coronavirus infectious bronchitis virus". The Journal of ... Tombus virus defective interfering (DI) RNA region 3 Dalton, K; Casais R; Shaw K; Stirrups K; Evans S; Britton P; Brown TD; ... The helper virus identifies and responds to signals within the IBV D-RNA that are responsible for replication and packaging of ...

*Bamboo mosaic virus satellite RNA cis-regulatory element

The bamboo mosaic virus satellite RNA cis-regulatory element is an RNA element found in the 5' UTR of the genome of the bamboo ... Page for Bamboo mosaic virus satellite RNA cis-regulatory element at Rfam. ... mosaic virus. This element is thought to be essential for efficient RNA replication. Bamboo mosaic potexvirus (BaMV) cis- ... regulatory element Potato virus X cis-acting regulatory element Poxvirus AX element late mRNA cis-regulatory element Annamalai ...

*Epstein-Barr virus small nucleolar RNA 1

Epstein-Barr virus stable intronic sequence RNAs Hutzinger, R.; Feederle, R.; Mrazek, J.; Schiefermeier, N.; Balwierz, J.; ... "Expression and processing of a small nucleolar RNA from the Epstein-Barr virus genome" (Free full text). PLoS Pathogens. 5 (8 ... Page for human herpesvirus 1 small nucleolar RNA at Rfam Page for EBER1 at Rfam Page for v-snoRNA1 at Rfam Page for IRES EBNA ... V-snoRNA1 is a box CD-snoRNA[clarification needed] identified in B lymphocytes infected with the Epstein-Barr virus (human ...

*Epstein-Barr virus-encoded small RNAs

"RNA families in Epstein-Barr virus". RNA Biology. 11 (1): 10-7. doi:10.4161/rna.27488. PMC 3929418 . PMID 24441309. Komano, J; ... an Epstein-Barr virus noncoding RNA, recruit human ribosomal protein L22". RNA. 12 (5): 872-82. doi:10.1261/rna.2339606. PMC ... "RNA families in Epstein-Barr virus". RNA Biology. 11 (1): 10-7. doi:10.4161/rna.27488. PMC 3929418 . PMID 24441309. Page for ... The Epstein-Barr virus-encoded small RNAs (EBERs) are small non-coding RNAs localized in the nucleus of human cells infected ...

*Epstein-Barr virus stable intronic-sequence RNAs

... (ebv-sisRNAs) are a class of non-coding RNAs generated by repeat introns in ... "The RNA WikiProject: Community annotation of RNA families". RNA. 14 (12): 2462-2464. doi:10.1261/rna.1200508. PMC 2590952 . ... however the virus generates proteins and RNAs to modulate host-virus interactions that maintain latent infection. In ways yet ... "Genome-wide analyses of Epstein-Barr virus reveal conserved RNA structures and a novel stable intronic sequence RNA". BMC ...

*Tombus virus defective interfering (DI) RNA region 3

Infectious bronchitis virus D-RNA Red clover necrotic mosaic virus translation enhancer elements Ray D, White KA (2003). "An ... Tombus virus defective interfering (DI) RNA region 3 is an important cis-regulatory region identified in the 3' UTR of ... Page for Tombus virus defective interfering (DI) RNA region 3 at Rfam. ... internally located RNA hairpin enhances replication of Tomato bushy stunt virus RNAs". J. Virol. 77 (1): 245-57. doi:10.1128/ ...

*Alfalfa mosaic virus coat protein binding (CPB) RNA

The Alfalfa mosaic virus (AMV) coat protein binding (CPB) RNA is an RNA element which is found in the 3' UTR of the genome. AMV ... Alfalfa mosaic virus RNA 1 5' UTR stem-loop Neeleman, L; Linthorst HJ; Bol JF (2004). "Efficient translation of alfamovirus ... Page for Alfalfa mosaic virus coat protein binding (CPB) RNA at Rfam. ... RNAs requires the binding of coat protein dimers to the 3' termini of the viral RNAs". J Gen Virol. 85 (Pt 1): 231-240. doi: ...

*Hypoviridae

Replication follows the double-stranded RNA virus replication model. Double-stranded rna virus transcription is the method of ... "Virus Taxonomy: 2014 Release". Retrieved 15 June 2015. Dolja, V. V.; Koonin, E. V. (2012). "Capsid-Less RNA Viruses". ELS. doi: ... The virus exits the host cell by cell to cell movement. Fungi serve as the natural host. The virus never leaves its host and ... Hypoviridae was the first family of viruses described that lacked a capsid. and does not assemble any virion to spread. Viral ...

*Endornaviridae

Replication follows the double-stranded RNA virus replication model. Double-stranded rna virus transcription is the method of ... "Virus Taxonomy: 2014 Release". Retrieved 15 June 2015. Dolja, Valerian V (2001). "Capsid-Less RNA Viruses". eLS. doi:10.1002/ ... The virus exits the host cell by cell to cell movement. Plants, fungi, and oomycetes serve as the natural host. Transmission ... Endornaviridae is a family of viruses. Plants, fungi, and oomycetes serve as natural hosts. There are currently eight species ...

*Viral disease

All are RNA viruses. Only one family of enveloped viruses causes gastroenteritis (Coronaviridae). All other viruses associated ... There is one family with a double-stranded RNA genome: Reoviridae. There is one additional virus (Hepatitis D virus) which has ... As a general rule, DNA viruses replicate within the nucleus while RNA viruses replicate within the cytoplasm. Exceptions are ... These viruses are enveloped. There is one family of single-stranded DNA viruses that infect humans: Parvoviridae. These viruses ...

*Quasispecies model

"RNA virus populations as quasispecies". Genetic Diversity of RNA Viruses. Domingo, E. (2002). "Quasispecies theory in virology ... Mutational clouds as predicted by the quasispecies model have been observed in RNA viruses and in in vitro RNA replication. The ... Martinez, MA, Martus G, Capel E, Parera M, Franco S, Nevot M (2012) Quasispecies Dynamics of RNA Viruses. In: Viruses: ... Burch CL, Chao L (2000). "Evolvability of an RNA virus is determined by its mutational neighbourhood". Nature. 406 (6796): 625- ...

*Reassortment

Why do RNA viruses recombine? offers a good introduction with figures on the concept of reassortment (as well as recombination ... In particular, reassortment occurs among influenza viruses, whose genomes consist of eight distinct segments of RNA. These ... The 1957 and 1968 pandemic flu strains were caused by reassortment between an avian virus and a human virus, whereas the H1N1 ... If a single host (a human, a chicken, or other animal) is infected by two different strains of the influenza virus, then it is ...

*Meteorus leviventris

Renault, Sylvaine (2012). "RNA Viruses in Parasitoid Wasps". Parasitoid Viruses Symbionts and Pathogens. Pivnick, Kenneth ( ... They have been shown to carry Rioviridae RNA viruses, one of only a few parasitoids to carry them. Quicke, Donald (22 December ... Beckage, Nancy (2011). Parasitoid Viruses: Symbionts and Pathogens. p. 194. ...

*Microevolution

Viruses that use RNA as their genetic material have rapid mutation rates, which can be an advantage since these viruses will ... Without proofreading error rates are a thousandfold higher; because many viruses rely on DNA and RNA polymerases that lack ... CS1 maint: Multiple names: authors list (link) Drake JW, Holland JJ; Holland (1999). "Mutation rates among RNA viruses". Proc. ... Viruses can also carry DNA between organisms, allowing transfer of genes even across biological domains. Large-scale gene ...

*Genetic code

Viruses that use RNA as their genetic material have rapid mutation rates, which can be an advantage, since these viruses ... Drake JW, Holland JJ (Nov 1999). "Mutation rates among RNA viruses". Proceedings of the National Academy of Sciences of the ... In line with the RNA world hypothesis, transfer RNA molecules appear to have evolved before modern aminoacyl-tRNA synthetases, ... preventing the ancient equivalent of viruses from overwhelming the RNA world. Stop codons: Codons for translational stops are ...

*Synthetic virology

... there is no RNA-equivalent for PCR). For many virus families the naked genome DNA (or RNA following transcription) is ... it is not the viruses that are synthesized, but rather their DNA genome at first, both in the case of DNA and RNA viruses, ... Nanofabricated synthetic viruses do not contain viral genes and do not have a capacity to replicate. Live synthetic viruses ... Such synthetic "DNA" viruses mimic the physiology of enveloped viruses, for example by: 1) cell membrane fusion catalysis, 2) ...

*Species

Viruses have enormous populations, are doubtfully living since they consist of little more than a string of DNA or RNA in a ... "Experimental evolution of plant RNA viruses". Heredity. 100 (5): 478-483. doi:10.1038/sj.hdy.6801088. Barton, N. H. (June 2010 ... Viruses are a special case, driven by a balance of mutation and selection, and can be treated as quasispecies. As a practical ... Viruses can transfer genes between species. Bacteria can exchange plasmids with bacteria of other species, including some ...
A negative-sense single-stranded RNA virus (or (-)ssRNA virus) is a virus that uses negative sense, single-stranded RNA as its genetic material. Single stranded RNA viruses are classified as positive or negative depending on the sense or polarity of the RNA. The negative viral RNA is complementary to the mRNA and must be converted to a positive RNA by RNA polymerase before translation. Therefore, the purified RNA of a negative sense virus is not infectious by itself, as it needs to be converted to a positive sense RNA for replication. These viruses belong to Group V on the Baltimore classification. In addition, negative-sense single-stranded RNA viruses have complex genomic sequences, cell cycles, and replication habits that use various protein complexes to arrange in specific conformations and carry out necessary processes for survival and reproduction of their genomic sequences. The complexity of negative-sense single-stranded RNA viruses carries into its ability to suppress the innate immune ...
A positive-sense single-stranded RNA virus (or (+)ssRNA virus) is a virus that uses positive sense, single-stranded RNA as its genetic material. Single stranded RNA viruses are classified as positive or negative depending on the sense or polarity of the RNA. The positive-sense viral RNA genome can also serve as messenger RNA and can be translated into protein in the host cell. Positive-sense ssRNA viruses belong to Group IV in the Baltimore classification. 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. Positive-sense ssRNA viruses have genetic material that can function both as a genome and as messenger RNA; it can be directly translated into protein in the host cell by host ribosomes. The first proteins to be expressed after infection serve genome ...
Expanding networks of RNA virus evolution. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
Hepatitis C trojan (HCV) is an enveloped, positive strand RNA computer virus of about 9. attributable to inherently different properties of low density particles, to association of these particles with factors stimulating fusion, or to co-floatation of factors enhancing fusion activity in genus of the Flaviviridae family (1). Based on sequence comparison, patient isolates are classified into seven genotypes, differing in their nucleotide sequence by 30C35% (2C5). The two viral surface proteins, E1 (residues 192C383) and E2 (residues 384C746), are processed by transmission peptidases of the endoplasmic reticulum from a 3,000-amino acid-long polyprotein encoded by the HCV genome (examined in Ref. 2). The E1 (31 kDa) and E2 (70 kDa) proteins are glycosylated in their large amino-terminal ectodomains (6) and are anchored in the viral membrane by their carboxyl-terminal transmembrane domains. E1 and E2 form a heterodimer stabilized by noncovalent interactions. This oligomer is usually thought to be ...
Summary of Facts and Submissions. I. European patent No. 0 846 181 with the title cDNA corresponding to the antigenome of nonsegmented negative strand RNA viruses, and process for the production of such viruses encoding additional antigenically active proteins was granted on European patent application No. 96928446.2 (published as WO 97/06270). The patent was granted with 21 claims.. II. Claim 1 of the patent as granted read as follows:. 1. A method for the production of an infectious non-segmented negative-strand RNA virus of the family Paramyxoviridae comprising. (a) introducing a cDNA molecule contained in a plasmid, wherein said cDNA molecule comprises the entire (+)-strand sequence of said negative- strand RNA virus operatively linked to an expression control sequence, which allows the synthesis of anti-genomic RNA transcripts bearing the authentic 3 -termini, and wherein said cDNA molecule consists of an integral multiple of six nucleotides, into a helper cell expressing an ...
Zika Virus Ns5 Monoclonals Zika Virus Reagents Research Reagents Biofront Technologies. Zika virus is a single positive strand RNA virus with a genome that encodes three structural proteins and seven non-structural (NS) proteins: NS1, NS2A, NS2B, NS3, NS4A, NS4B and NS5. The flavivirus NS5 protein is the largest of the NS proteins and possesses enzymatic activities required for the synthesis of the 11 kb viral RNA genome, making it essential for replication and a prime target for drug candidates. Zika NS5 Mab 6A1 100 ug Zika NS5 Mab 6A1 500 ug Zika NS5 Mab 6A1 1 mg Zika NS5 Mab 8B8 100 ug Zika NS5 Mab 8B8 500 ug Zika NS5 Mab 8B8 1 mg Zika NS5 Mab 7A9 100 ug Zika NS5 Mab 7A9 500 ug Zika NS5 Mab 7A9 1mg
In the summer of 2005, Giau was a REU intern in Dr. C. Kaos lab at Texas A&M University. Her project was titled, "Visualization of Fluorescent Brome Mosaic Virus RNA3 in an In-vivo Environment.". During my stay at Texas, I worked with a plant virus called Brome Mosaic Virus. In recent years, this virus has become a model system for positive strand RNA viruses.. The internship was a rewarding experience because it was my first time being exposed to scientific research on a larger scale. Within one lab there were at least 4-5 large scale projects going on. It was definately an "action-packed" environment for science majors.. Secondly, I was very amazed to see how these scientists were so dedicated to their work. The Post-doc that I worked under spent at least 12 hours a day in the lab during weekdays, and he was always in the lab on the weekends as well. Through this internship I found out that the lab is where I want to be in the future.. Giau graduated magna cum laude with a double major in ...
In the summer of 2005, Giau was a REU intern in Dr. C. Kaos lab at Texas A&M University. Her project was titled, "Visualization of Fluorescent Brome Mosaic Virus RNA3 in an In-vivo Environment.". During my stay at Texas, I worked with a plant virus called Brome Mosaic Virus. In recent years, this virus has become a model system for positive strand RNA viruses.. The internship was a rewarding experience because it was my first time being exposed to scientific research on a larger scale. Within one lab there were at least 4-5 large scale projects going on. It was definately an "action-packed" environment for science majors.. Secondly, I was very amazed to see how these scientists were so dedicated to their work. The Post-doc that I worked under spent at least 12 hours a day in the lab during weekdays, and he was always in the lab on the weekends as well. Through this internship I found out that the lab is where I want to be in the future.. Giau graduated magna cum laude with a double major in ...
RNA-affinity chromatography assays are used to identify proteins binding specific RNA sequences. These proteins represent potential factors contributing to the function of RNA molecules. In our lab, we have used this protocol to identify proteins binding sequence motifs involved in replication and transcription of positive strand RNA viruses. The assay described in this protocol consists on the immobilization of 5-biotinylated RNA oligonucleotides (30-40 nt) on a streptavidin-conjugated, paramagnetic solid matrix. Then, cytoplasmic protein extracts pre-cleared on the solid matrix to decrease nonspecific binding, were incubated with the immobilized RNA molecules in the presence of a nonspecific competitor. RNA-protein complexes immobilized on the paramagnetic solid matrix were isolated using a magnet and the bound proteins were separated by polyacrylamide gel electrophoresis for proteomic analysis.
Flu viruses contain 8 strands of RNA, which code for 10 proteins. If two flu viruses infect a cell at the same time, new viruses budding from that cell can contain a mixture of RNA strands from the two original viruses - a phenomenon called reassortment. However, Dr. Blankenship says that the way RNA viruses are recombining are not repeated reassortments but cut and paste configurations that only genetic engineers and viral specialists have the ability to design.. Mutation is the major cause of changes in the genetic code of the viruses. Scientists have claimed that RNA mutation is higher because RNA enzymes are more likely to commit errors, however the mutation rates, their frequency and configurations are now unprecedented.. Weaponized Programs?. In DNA viruses, viral genetic code is injected in the host DNA for duplication and decoding. RNA viruses skip DNA for duplication and decoding. Scientists have used the unique ability of RNA viruses to create stronger versions that break down the ...
Single-stranded RNA viruses have evolved to survive extremely high mutation rates.The ubiquity and effect of ssRNA viral diseases makes an understanding of the theoretical and mechanical underpinnings of rapid viral evolution vital to our ability to control them. In this body of work, we explore some of the ways in which ssRNA viruses can uncouple the rate at which variation is generated (mutation rate) from the rate at which variation is observed (measured rate of molecular evolution).. ...
The concept of the viral species has been a hard one to determine becuase viruses dont reproduce sexually. It is generally thought to be rather a arbitrary classification, however, most virus species tend to be phylogenetically and often phenotypically stable genetic lineages and hence may be thought of as biological relevant. We may think of viral speciation much like we think of speciation in the classic sense: allopatric or geographical speciation (virus adaptation to a new host species) and sympatric - that not requiring the forces of georgaphic isolation (generation of viral speciation within a single host). Virus sympatric speciation requires the adapation to a new infectious niche within a host, for example a new lineage may infect new cell types within that host. Virus allopatric speciation requires host-jumping or adaptation to a new host altogether but may result from co-divergence follwoing host speciation. Both processes may result in two or more stable, phylogenetic and ...
RNA viruses have been isolated that infect marine organisms ranging from bacteria to whales, but little is known about the composition and population structure of the in situ marine RNA virus community. In a recent study, the majority of three genomes of previously unknown positive-sense single-stranded (ss) RNA viruses were assembled from reverse-transcribed whole-genome shotgun libraries. The present contribution comparatively analyzes these genomes with respect to representative viruses from established viral taxa. Two of the genomes (JP-A and JP-B), appear to be polycistronic viruses in the proposed order Picornavirales that fall into a well-supported clade of marine picorna-like viruses, the characterized members of which all infect marine protists. A temporal and geographic survey indicates that the JP genomes are persistent and widespread in British Columbia waters. The third genome, SOG, encodes a putative RNA-dependent RNA polymerase (RdRp) that is related to the RdRp of viruses in the family
RNA virus replication machineries.(A) RdRps of hepatitis C virus and reovirus. Hepatitis C virus is a (+)RNA virus from the Flaviviridae family, while reovirus
Single stranded RNA (ssRNA) viruses are an incredibly diverse viral group capable of infecting plants and animals. Common ssRNA viruses causing human disease are picornaviridae (rhinovirus [the common cold], polio), coronoaviridae (SARS, MERS), and filoviridae (Ebola, Marburg). Positive ssRNA viruses have their genetic material directly translated into usable proteins, while negative ssRNA viruses use an RNA replicase enzyme to convert their genetic material to positive strands before being used to make proteins. As evidenced by the efficacy of the seasonal flu vaccine and the ongoing trials for an Ebola cure, pharmacological interventions to cure a ssRNA infection are few and far between.. Now, years after original research was published on ssRNA packaging within a cell, the English researchers have shown that viral RNA induces conformational changes in capsid proteins, essentially telling the viral packaging it is ready to bud from the infected cell. Previous research from this group showed ...
By the analysis of thermodynamic RNA secondary structure predictions, we previously obtained evidence for evolutionarily conserved large-scale ordering of RNA virus genomes (P. Simmonds, A. Tuplin, and D.J. Evans, RNA 10: 1337-1351, 2004). Genome-scale ordered RNA structure (GORS) was widely distributed in many animal and plant viruses, much greater in extent than RNA structures required for viral translation or replication, but in mammalian viruses was associated with host persistence. To substantiate the existence of large-scale RNA structure differences between viruses, a large set of alignments of mammalian RNA viruses and rRNA sequences as controls were examined by thermodynamic methods (to calculate minimum free energy differences) and by algorithmically independent RNAz and Pfold methods. These methods produced generally concordant results and identified substantial differences in the degrees of evolutionarily conserved, sequence order-dependent RNA secondary structure between virus ...
Genome RNA replication of all (+)RNA viruses takes place in close association with rearranged intracellular membranes. We are only beginning to understand the biogenesis and ultrastructure of these virus-induced membrane structures. In collaboration with the virology groups of LUMC (Prof. Dr. Eric Snijder) and the University of Utrecht (Prof. Dr. Frank van Kuppeveld), EM and tomography approaches will be used to gain more insight into the architecture of the rearranged membranes, the localization of the viral replication enzymes, and the localization of host factors that are hijacked by picornavirus to facilitate replication of their RNA genome.. Host institute ...
RNA viruses generally have very high mutation rates as they lack DNA polymerases which can find and fix mistakes, and are therefore unable to conduct DNA repair of damaged genetic material. DNA viruses have considerably lower mutation rates due to the proof-reading ability of DNA polymerases within the host cell. Retroviruses integrate a DNA intermediate of their RNA genome into the host genome, and therefore have a higher chance of correcting any mistakes in their genome thanks to the action of proof-reading DNA polymerases belonging to the host cell. Although RNA usually mutates rapidly, recent work found that the SARS virus and related RNA viruses contain a gene that mutates very slowly.[4] The gene in question has a complex three-dimensional structure which is hypothesized to provide a chemical function necessary for viral propagation, perhaps as a ribozyme. If so, most mutations would render it unfit for that purpose and would not propagate. ...
RNA viruses generally have very high mutation rates as they lack DNA polymerases which can find and fix mistakes, and are therefore unable to conduct DNA repair of damaged genetic material. DNA viruses have considerably lower mutation rates due to the proof-reading ability of DNA polymerases within the host cell. Retroviruses integrate a DNA intermediate of their RNA genome into the host genome, and therefore have a higher chance of correcting any mistakes in their genome thanks to the action of proof-reading DNA polymerases belonging to the host cell. Although RNA usually mutates rapidly, recent work found that the SARS virus and related RNA viruses contain a gene that mutates very slowly.[4] The gene in question has a complex three-dimensional structure which is hypothesized to provide a chemical function necessary for viral propagation, perhaps as a ribozyme. If so, most mutations would render it unfit for that purpose and would not propagate. ...
Previously, I have argued that in order to understand the origin of RNA viruses, it is imperative to completely ignore the mainstream view that a major part of our genome is made of the genetic debris of ancient inva-sions of RNA viruses. Instead, I have hypothesized that transposable and transposed elements might have been originally designed to generate variation in offspring and should therefore be renamed variation-and-integrity assuring genetic elements (short: VIGEs). Hence, the major part of genomes contains VIGEs and their degenerate remnants. As mentioned above, ERVs are mobile genetic elementscharacterized by gag and pol genes that closely resemble full-blown RNA viruses, such as influenza and human immunodeficiency viruses. The origin of such RNA viruses can therefore be understood as a transformed ERV. In other words, RNA viruses may form in genomes from gag-pol elements. Gag-pol elements may trans-mute into RNA viruses through sequential uptake and/or recombination of genomic ...
Zika virus, computer illustration. This is an RNA (ribonucleic acid) virus from the Flaviviridae family. It is transmitted to humans via the bite of an infected Aedes sp. mosquito. It causes zika fever, a mild disease with symptoms including rash, joint pain and conjunctivitis. In 2015 a previously unknown connection between Zika infection in pregnant women and microcephaly (small head) in newborns was reported. This can cause miscarriage or death soon after birth, or lead to developmental delays and disorders. - Stock Image F012/9109
RNA viruses provide unique insights into the patterns and processes of evolutionary change in real time. The study of viral evolution is especially topical given the growing awareness that emerging and re-emerging diseases (most of which are caused by RNA viruses) represent a major threat to public health.
RNA viruses provide unique insights into the patterns and processes of evolutionary change in real time. The study of viral evolution is especially topical given the growing awareness that emerging and re-emerging diseases (most of which are caused by RNA viruses) represent a major threat to public health.
Students working in pairs or small groups receive a simulated virus: two paper cups taped together, enclosing a strip of paper listing an RNA or DNA sequence (an abbreviated viral genome). The students break open the cups (simulating viral uncoating in the host cell) and decide how host and/or viral enzymes will convert the genome into viral proteins and new genomes. The sequences provided describe a double-stranded DNA virus, single-stranded RNA viruses (+ or - strand), a retrovirus, and a double-stranded RNA virus. Templates for photocopying the genomes, sample worksheets, and an instructors answer key are included.
Preface. .. Part I: What is a virus?:.. 1. Towards a Definition of a Virus.. 2. Some Methods for Studying Animal Viruses.. 3. The Structure of Virus Particles.. 4. Classification of Viruses.. Part II: Virus Growth in Cells:.. 5. The Process of Infection: I. Attachment of Viruses and the Entry of Their Genomes into the Target Cell.. 6. The Process of Infection: IIA. The Replication of Viral DNA.. 7. The Process of Infection: IIB. Genome Replication in RNA Viruses.. 8. The Process of Infection: IIC. The Replication of RNA Viruses with a DNA Intermediate and Vice Versa.. 9. The Process of Infection: IIIA. Gene Expression in DNA Viruses and Reverse-Transcribing Viruses.. 10. The Process of Infection: IIIB. Gene Expression and its Regulation in RNA Viruses.. 11. The Process of Infection: IV. The Assembly of Viruses.. Part III: Virus Interactions with the Whole Organism:.. 12. The Immune System and Virus Neutralization.. 13. Interactions Between Animal Viruses and Cells.. 14. Animal Virus-Host ...
InterPro provides functional analysis of proteins by classifying them into families and predicting domains and important sites. We combine protein signatures from a number of member databases into a single searchable resource, capitalising on their individual strengths to produce a powerful integrated database and diagnostic tool.
Definition of RNA virus in US English - a virus in which the genetic information is stored in the form of RNA (as opposed to DNA).
Newly discovered insect RNA viruses in China. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
Medical Mnemonics - RNA Viruses: Negative Stranded - Microbiology Mnemonics - Looking for a MKSAP alternative? Try the Knowmedge ABIM Internal Medicine Qbank.
two. a pc code that may be inserted right into a application to damage data or bring about glitches. virus فيروس في الكومبيوتر комп. вирус vírus virus der Virus virus ιός Η/Υ virus arvutiviirus ویروس virus virusוירוס वाइरस, विषाणु virus (računalni) számítógépes vírus virus komputer virus コンピューターウイルス 컴퓨터 바이러스 (kompiuterio) virusas datorvīruss virus virusvirus wirus komputerowy زهر вирус počítačový vírus virus virus datavirus ไวรัสคอมพิวเตอร์ virüs 電腦病毒 вірус وائرس، کمپيوٹر نظام کو تباہ کرنے والا کوڈ vi rút máy tính 计算机病 ...
About 95 per cent of us are infected with the Epstein-Barr virus. Cancer Virus is the compelling, thriller-like tale of its discovery
Viruses are small, self-replicating nucleic acid/protein aggregates that depend on the metabolism of their host cell for replication. Viruses do not have their own metabolism; it is thus a question whether viruses can be considered a life form. The genome of a virus can be single- or double-stranded DNA or RNA. Viruses can have a very simple structure and may consist of only a nucleic acid with a protein shell (capsid) for protection. Some viruses pathogenic to animals have a more complex structure: their capsid is surrounded by a membrane made of lipids and glycoproteins that originates in the membrane of the host cell. Viruses that multiply in bacteria are called bacteriophages.. In humans, viruses cause many diseases, including measles, mumps, rubella, chicken pox, rabies, hepatitis, or influenza; some cancers are also related to viral infections (e.g. papilloma viruses). There are vaccines against some of these diseases; the use of antibiotics does not help against viruses. ...
Personally I think this may be a bit too curmudgeony. The campaign clearly had the desired effect by showing, well, that microbes can grow fast. So the microbes they used were not viruses. And so the ones they used were not harmful. It still is creepy in a way. It is a fine balance of course. We (the royal we here) want to promote microbes as being fun. And we also want to promote them as not always being dangerous. But microbes also do kill a lot of people. And this billboard will probably do more to get people talking and thinking about bacteria and mold than any other movie promotion in recent memory ...
Viruses that contain RNA as their genetic information are called RNA viruses, and of this family, Hepatitis C is a prime example. RNA viruses have similar shapes and perform similar functions as...
For more information about how parvo affects dogs, visit www.orlandosentinel.com/newsThe worst outbreak in memory of a fatal dog disease has forced the Orange County animal-control department to
Applies to: Exchange Server 2010 SP3, Exchange Server 2010 SP2. Topic Last Modified: 2012-07-23. You can use the Edge Rules agent and transport rules in Microsoft Exchange Server 2010 to help protect your organization from viruses.. New viruses threaten organizations every day. To minimize the damage caused by viruses, antivirus vendors and administrators must respond to virus threats as soon as possible. Despite a quick response, there will be a gap between the time that a virus threat appears and the time that a solution becomes available. This gap, when a virus threat remains unknown and unresolved, is called a zero-day virus threat. At the same time, viruses that have been circulating on the Internet for many years also continue to pose a significant threat to organizations. Although the majority of these viruses can be identified by antivirus scanners, antivirus scanners may be taken offline by mistake, updated with out-of-date definitions, or experience other problems that make them ...
A virus consists of a protein mantle that encapsulates a strand of DNA or RNA, either single-stranded or double-stranded. The DNA or RNA is injected into a cell nucleus, where the machinery of the cell takes the code and produces many more copies of the virus. These copies "break out" of the cell and each may go on to "infect" another cell and repeat the process. Some infections are benign to the cell and organism, while some cause rapid cell death and serious disease. Virus particles can be released from the host cell either by budding of the phospholipid membrane or by traumatic lysing. It is assumed that viral infection occurs passively, with the virus pathogen being delivered to its preferred host by Brownian motion and natural circulatory and behavioral processes of the organism. It is difficult, however, to observe a virus in situ due to the limitations of modern microscopes. Viruses are very small, with a typical size between 40 and 100 nm (1 nm = 10-9 m, nm=nanometer). The term "virus" ...
Among the diverse strategies used by viruses to induce human disease, their ability to cause immune defects has received increasing attention, concurrently with the identification of cells able to...
usr/bin/perl -w use strict; my $gCurRec; foreach(qw(name to file action virus)) { $gCurRec-,{$_}=; } while(,DATA,) { $gCurRec-,{name}=$1 if (/^From:\s*(.+?)\s*$/); $gCurRec-,{to}=$1 if (/^To:\s*(.+?)\s*$/); $gCurRec-,{file}=$1 if (/^File:\s*(.+?)\s*$/); $gCurRec-,{action}=$1 if (/^Action:\s*(.+?)\s*$/); $gCurRec-,{virus}=$1 if (/^Virus:\s*(.+?)\s*$/); if (/^-----/) { print $gCurRec-,{name},\t, $gCurRec-,{to},\t, $gCurRec-,{file},\t, $gCurRec-,{action},\t, $gCurRec-,{virus},\n; foreach(qw(name to file action virus)) { $gCurRec-,{$_}=; } } } __DATA__ From: [email protected] To: [email protected] File: value.scr Action: The uncleanable file is deleted. Virus: WORM_KLEZ.H ---------------------------------- Date: 06/30/2002 00:01:21 From: [email protected] To: [email protected] File: Nr.pif Action: The uncleanable file is deleted. Virus: WORM_KLEZ.H ...
how to get rid of virus using avira free , how to get rid of virus using avira antivirus , how to get rid of virus using avira download , how to get rid of virus using avira 2017 , how to get rid of virus using avira for mac , how to get rid of virus using avira update , how to get rid of virus using avira review ...
Virus DNA adalah virus yang materi genetiknya berupa asam nukleat yang berbentuk rantai ganda berpilin. Di dalam sel inangnya, DNA pada virus akan mengalami replikasi menjadi beberapa DNA dan juga akan mengalami transkripsi menjadi mRNA. mRNA akan mengalami translasi untuk menghasilkan protein selubung virus. Masih di dalam sel inang, DNA dan protein virus mengkonstruksikan diri…
Including internal DNA control for simultaneous purification of viral DNA and RNA from 1-5ml pooled serum or other liquid samples ...
Mac users have generally had less to worry about on the virus front than their Windows using counterparts, but there are still a fairly large number of Mac OS viruses floating around the Internet. Brought to attention by the latest "Simpsons" virus, Mac viruses can still cause major problems for those not aware of their presence or protected from their existence. For those interested in a description of most of the known Mac viruses, the SecurityPortal Web site is where to find that information.. Containing detailed descriptions of over 100 known Mac related viruses, the SecurityPortal Web site is a great place to start for anybody interested in the security of their system. According to SecurityPortal: ...
List of diseases caused by virus. We collect a list of Diseases caused by the virus.These diseases really dangerous for human.Viruses are the most common microbes influence people. These microscopic organisms spread easily, usually through person-to-person contact or by contact with body fluids such as blood, mucus or saliva. Once inside the body, quickly reproduce viruses that sometimes overwhelm the natural defenses of the body. When this happens, viruses can cause various diseases.. ...
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Sébastien Igonet, Marie-Christine Vaney, Clemens Vonrhein, Gérard Bricogne, Enrico A. Stura, Hans Hengartner, Bruno Eschli, and Félix A. Rey ...
Click here for ac virus pictures! You can also find pictures of pv virus, mild virus, melon virus, latent virus, influenza virus.
There is a difference between wishing to cause major damage and curiosity. I have heard of people actually going out to the Web, downloading a virus and then running it to see what it will do. They are often disappointed when they dont see a picture. Fictional virus portrayals have made people think that they have a graphical interface. Most are not graphical at all. This is one area where education would help. What should a user do if they think they have a virus? I always advise users to run a virus scan. I dont go in for looking at specific files or keys for a virus. A complete scan is much better. What does the future hold for virus management? When will users become savvier? I think well see operating systems and applications becoming more secure. Security software will also become better. But I also think well see users become more sophisticated. I see computer usage becoming more like driving. Driving is a complicated dance that has a lot of flavors to it that people have learned. For ...
Yet there were plenty of viruses in the wild to worry about such as W32/Yaha.E, which can arrive in an e-mail masquerading as a screensaver. There was also Worm.Frethem.D, which arrived purporting to be a decrypted password. Long-time pests such as Badtrans, Nimda and Sircam are still making the rounds. One interesting fact is most, if not all, of the top viruses in June were Windows 32 viruses, not Word macro or script viruses, said Chris Wraight, technology consultant at Sophos Americas. Worms and viruses that spread using networking functions or e-mail clients currently dominate inquiries to our customer support. Below are the monthly virus numbers from different antivirus vendors ...
I got this in my mail today!!! |Subject: Caution - new virus |A new virus called the C-Nile Virus cannot be killed even by |Nortons most | advanced programs. Be warned! It appears to hit those who were |born |during or before | 1953.
begingroup$ Very true. Im looking specifically for any sort of shared sequence that is necessary for the survival of all viruses. At first I thought (for RNA viruses at least) it would be some sequence in a gene that codes for reverse transcriptase, however I have yet to find such a sequence. Any suggestions for a sequence like this or any other would be very greatly appreciated, so feel free to mention any ideas you might think of. $\endgroup$ - CDB Feb 23 15 at 20:57 ...
Our team of expert virologists can help you to design a range of viral expression systems for your research needs. They have previous expertise in working with both single and double stranded DNA viruses, and developing new reverse genetics systems for both positive and negative sense RNA viruses. Please contact us for further information. ...
10/17 Some iPods shipped w/ a Windows Virus: http://www.apple.com/support/windowsvirus \- why dont more viruses delete massive amounts of data? it seems like if the virus writers wanted to hurt msft that what they should do in addition to spreading. it seems like viruses are still in the realm of annoying rather than fatal. is there some techical reason they cant do more permanent damage? [i understand thaty cant instantly kill the host, as that will greatly reduce the spread rate]. \_ one day they will take your data and youll have to pay Russians to get it back. \_ Probably because most of these are all about tagging to get their name out there in the el8 hax0r community to announce their [email protected] sk1llz than really about anything truly malicious. We have spyware for that now. \_ sort of like the reason real viruses arent more lethal .. they kill off the host and cant spread any more. \- yes i understand that is often the case but you would think there would be at least a few that did massive ...
Tuvaro.com is a deceitful site that you should never trust in because it wont help you to remove any virus or Trojan on your PC while causing more damage on your PC. If your PC is infected by Tuvaro.com virus, it is advisable to manually remove it so that the virus can be totally gone from your PC and it wont come back to bother your PC again. You cannot be soft-hearted to this malicious redirect virus, but had better take the action to handle this pest as soon as possible ...
Cancer killer viruses cant get to the cancer cells, because the immune system detects them and destroys them before they do. HIV/AIDS viruses, however, are NOT detected and attacked by the immune sys
I have just been alerted that our LAN was infected with the "wazzu.a" macro virus. Thus, any mailings from this system potentially could have carried the virus. Please run a macro virus scan on your systems. If you dont have an up-to-date one, check with Frisk Software international on the Internet and download F-MACROW to scan and clean out macro viruses. I apologize for any inconvenience this may have caused, but I hope you catch it much sooner than I did. Alison L. Hess Agricultural Conservation Innovation Center ...
There are many different types of virus according to there infection or according to there fucntionality. Polymorphic Viruses There viruses change there behaviour as they infect a system. Stealth Viruses They can hide themselves from AV. Fast and Slow Infectors
Problem : Describe the lytic and lysogenic phases found in some viruses. In the lytic phase virus particles infect host cells and are replicated. In the lysogenic phase, however, viral genetic material that has entered the host cell becomes incorportated in the cell and lies dormant. It is then passed on to the progeny of the infected cells. Eventually, the lytic phase will start again, and cells that were never infected themselves, but carry the viral genetic material will begin to produce new virus particles ...
As a retrovirus, HIV is an RNA virus that codes for the enzyme reverse transcriptase, which transcribes the viral genomic RNA into a DNA copy that ...
By using the ability of the positive-strand RNA ((+)RNA) virus BMV to replicate in yeast it was previously shown that subunits of the LSm1-7 ring, as well as Pat1 and Dhh1 play an essential role in the transit of the BMV ...
Get an answer for Please fill in the blanks: A virus consists of a ___ coat and a ___ core; and a viruss genetic material is found _____;and a bacteria cells genetic material is found ____. and find homework help for other Science questions at eNotes
I got info about virus on net.So checked accordingly, found $Recycle.bin virus in my C drive, how to remove, if it is a virus, without deleting windows related files, if at all existing here. ...
Your email to user [email protected] contained a VIRUS and was not delivered. Remove the virus in your attachment and resend. Thank you, IT Department, IEE ====================================== VIRUS Report: ====================================== /var/tmp/avpcheck6jdVJb archive: Mail /var/tmp/avpcheck6jdVJb/[From ,[email protected],][Date Wed, 20 Aug 2003 10:26:42 +0200]/UNNAMED ok. /var/tmp/avpcheck6jdVJb/[From ,[email protected],][Date Wed, 20 Aug 2003 10:26:42 +0200]/text infected: I-Worm.Sobig.txt ...
Slide set: Viruses have always lived among humans, and they killed many millions of people. In fact, without a host, these microscopic parasites cannot reproduce or survive. As scientists discover the chemical rules by which each virus plays, they can begin to control how a virus affects us. Companion slide set to the video, Viruses.
Slide set: Viruses have always lived among humans, and they killed many millions of people. In fact, without a host, these microscopic parasites cannot reproduce or survive. As scientists discover the chemical rules by which each virus plays, they can begin to control how a virus affects us. Companion slide set to the video, Viruses.
... Common cols is caused by virus.Viruses cannot exist on their own and for survival they need to spread to another host.
you may want to try going into safe mode. ----- Original Message ----- From: DH Holmes ,[email protected], To: ,[email protected], Sent: Thursday, October 06, 2005 4:00 PM Subject: -=PCTechTalk=- Re: Need Help with Virus , Don, , Have you tried the System Restore trick? If this virus is located in , those files it is not, apparently, going to be deleted by an AV prog. , , The fix is simple, but is done at the cost of losing all previous , footprints of your system. Go to System restore and disable System , Restore. Reboot(a MUST), then Re-enable System Restore and create a , restore point(important). That will be the ONLY restore point you will , have, all earlier ones being deleted. That may solve your problem. I , cant tell. , , Just remember that all your previous restore points are lost when you , disable!!!! , , HTH , , Rick H , , [email protected] wrote: ,, I dont think people really read the description of my problem. ,, I cant use an on line scanner if the virus keeps me ...
E stato rilevato un virus nel messaggio di posta elettronica! --- Scan information follows --- Result: Virus Detected Virus Name: [email protected] File Attachment: your_details.pif Attachment Status: deleted --- Original message information follows --- From: ,[email protected], To: ,[email protected], Date: Mon, 8 Sep 2003 7:29:01 +0300 Subject: Re: Thank you! Message-Id: ,[email protected], Received: from EXTSMTP2.uni.net ([127.0.0.1]) by EXTSMTP2.uni.net (NAVGW 2.5.1.2) with SMTP id M2003090806285524400 for ,[email protected],; Mon, 08 Sep 2003 06:28:55 +0200 ...
Mimail virus variants have taken out five of the top ten spots in a new Sophos virus report of the most prolific viruses affecting businesses last ...
... ,CyberScrub Anti Virus 1.2 is CyberScrub AntiVirus Lifetime Edition provides state of the art Virus Protection
Anyone had SmartSecurity detect a program as a virus incorrectly? I know that people would not question when a virus program says that something is a...
hello world! I cant find the best anti virus to protect my PC using XP I Googled.. some says that bitdefender is #1 others says no the Kaspersky is the best.:( I think i will migrate to linux to protect my self from viruses!!:x which anti virus you use thanks
I use Zone Alarm, Avast Antivirus and Spybot, but on a recent scan the following viurses showed up:also I would like to have an idea of how I got these viruses and see below concerns about my start up files. Detected 6/28/07 Scanning of selected filesAction was completed successfully!Virus has been detected! File Name: A0081006.exe.vir FileID: 11 Virus Description: Win32:Trojan-gen. {VC} Scanning of selected files
Although there is no B12 Virus, there is a connection between Viruses and B12. It turns out that having higher B12 levels can inhibit some nasty viruses.
Hi Everyone, Would it ever be possible for a Mac to get a virus if there were Mac viruses floating around like PC viruses. What about...
Much beyond this rate, RNA viruses risk crossing an "error threshold," or the point at which there are too many deleterious mutations for the viral ...
A virus is a non-cellular genetic element that hijacks a cell for its own replication. In its extracellular state the virus particle ,also known as a vi...
Symantec announced its antivirus lab has discovered a new strain of viruses hidden within Microsoft Excel documents. A second variety of the relatively harmless Excel macro viruses, this new strain attaches blank pages to Excel documents and changes the phrase "Microsoft Excel" to "Microsofa Excel," according to Charles Renert, development manager at Symantec. The company says it is working on a cure.
This eMedTV segment provides a wealth of information on viruses and the conditions they cause. Articles discuss individual viruses in detail, including transmission methods, symptoms, treatment methods, and more.
Virus: Virus, an infectious agent of small size and simple composition that can multiply only in living cells of animals, plants, or bacteria.
Viruses cannot grow or reproduce, but they can manufacture copies of themselves by stealing protein mass and other nutrients from host cells. Viruses propagate exponentially, given adequate material...
This is the latest virus pattern to detect the latest viruses. This update will work on the following products: NAV 2000 for Win9x/NT/2000, NAV 2001 for Win95b/98/NT/2000/Me, NAV 2002 Professional E...
How do viruses resemble non-living things? Or Organise a discussion in your class on the topic. 'Are viruses living or non-living'?
Mensagem com vírus enviada aparentemente pelo remetente indicado. --- Scan information follows --- Result: Virus Detected Virus Name: [email protected] File Attachment: document_all02c.zip Attachment Status: deleted --- Original message information follows --- From: [email protected] To: [email protected] Date: Fri, 23 Apr 2004 18:35:03 -0300 Subject: Re: Hi Received: from agf2.agf.com.br ([128.250.115.2]) by agfrelay.agf.com.br (SAVSMTP 3.1.5.43) with SMTP id M2004042318393326700 for ,[email protected],; Fri, 23 Apr 2004 18:39:33 -0300 ...
25 September 1998 Virus difference worth exploitingKNOW which form of barley virus you are up against before choosing a variety.That is the message emergin
Ran Protector Plus virus program this morning and found W32/Virut.Gen virus located in NetWaiting exe file plus 7 other files which were quarantined. If I dele
Definition of virus: Infectious and parasitic microorganism much smaller than a bacterium, too small to be seen with a regular microscope or to be trapped even by ceramic filters. A virus is incapable of independent ...
1) Virus is a little program whos activity can destruct/destroy some files and a computer system. If this program does not open, its inactive and...
Vonage Dam virus came back.....I did contact AVG and did what they said....I went as far as logging into safemode and running the VS cwsshredder adaware sysbot avg and all seemed fine then that dam virus popped up again. I am now installing Norton which I d
avast! Virus Cleaner is a free tool that will completely remove selected viruses & worms from your computer: Badtrans, Beagle, Blaster, BugBear, Ganda, Klez, MiMail, MyDoom, Nimda, Opas, Scold, Sircam, Sober, Sobig, Swen, Yaha, incl. variants.
Health Abraham Rinquist October 14, 2016 Viruses challenge our definition of life. Neither dead nor alive, they are simply functional or not. Viruses do no
Play Virus 2 a free Puzzle at OneMoreLevel.com. Thousands of free addictive Flash games like Virus 2 and many more. Updated daily.
Hi, I'm stuck and need help badly. My PC has something drastically wrong with it, that i'm putting down to being a virus. A little while ago i noticed my PC (wh...
I have virus rootkit.trace and only(1)item which is this virus comes up in Malwarebytes. After i select to remove/quarintine it and run the program...
Hi, i contracted the moneypak virus while surfing the web. Ive seen this virus before and was able to remove it from a friends laptop with some avira
... Starting September 19, Sophos successfully became the lamest virus ever. An update put out by their auto-update service has rendered many machines across the world useless. This update detected false positives and deleted or quarantined them...
Quick, whats the most widely distributed virus or worm of all time? Its the Klez worm, which continues to top the virus tracking charts. Heres what to do about it.
In contrast to their negative reputation as disease causing agents, some viruses can perform crucial biological and evolutionary functions that help to
much_like_flipping_a_light_switch_the_hepatitis_c_virus_turns_on_human_immune_defenses_upon_entering_the_body_but_also_turns_off_those_defenses_by_manipulating_interaction_of_key_cellular_proteins_ut_southwestern_medical_center_researchers_have_found_
Genome replication in picornaviruses is catalyzed by a virally encoded RNA-dependent RNA polymerase, termed 3D. These viruses also use a small protein primer, named VPg, to initiate RNA replication. The recent explosion of structural information on picornaviral 3D polymerases has provided insights into the initiation of RNA synthesis and chain elongation. Comparing these data with results from previous structural analyses of viral RNA-dependent RNA polymerases that catalyze de novo RNA synthesis sheds light on the different strategies that these viruses use to initiate replication. © 2006 Elsevier Ltd. All rights reserved ...
The Cryphonectria parasitica gene cpmk2, which encodes a mitogen-activated protein kinase belonging to the yeast extracellular signalling-regulated kinase (YERK1) subfamily, was isolated and its biological function was examined. Disruption of cpmk2 resulted in impaired pigmentation and abolished conidiation. Growth defects were observed in the cpmk2 mutant grown on solid plates, but growth of the mutant appeared normal in liquid media, including EP complete and PD broth, suggesting that the cpmk2 gene is involved in sensing and responding to growth conditions. The mutant's production of laccase, as measured by the size of the coloured area produced on tannic-acid-supplemented plates, was significantly reduced compared with the wild-type, but the intensity of the coloured area was unchanged, suggesting that the reduced laccase activity was owing to reduced growth on solid media rather than transcriptional downregulation. A dramatic reduction observed in the canker area produced by the cpmk2 mutant
Two members of the Benyviridae family, Beet soil borne mosaic virus (BSBMV) and Beet necrotic yellow vein virus (BNYVV), possess identical genome organisation, host range and high sequence similarity. To understand functional differences in molecular biology, pathogenicity mechanisms, symptom expression as well as interaction with the host and between viral species, a reverse genetic system represents a prerequisite. Infectious cDNA full length clones of both viruses were constructed by isothermal in vitro recombination. Artificial formation of BNYVV and BSBMV RNA1+2 reassortants were viable and spread long distance in N. benthamiana. Small genomic RNAs were exchangeable and systemically infected B. macrocarpa. Moreover, fluorescence labelled full length clones were achieved by replacing a part of the RNA2 encoded coat protein read through domain. Co infection experiments with labelled BSBMV and BNYVV showed that both viruses remained spatially separated after N. benthamiana agroinoculation. In ...
American chestnut is a tree of great historical, ecological, and economical importance. It once dominated forests in eastern United States until the introduction of chestnut blight fungus (Cryphonectria parasitica) in the late 19th century. Within 50 years, C. parasitica killed almost all of the 4 billion American chestnut trees in the eastern United States. The fungus first infects wounded stem, secretes oxalic acid to decrease the pH of the infected tissue to toxic levels for the tree, but optimum for fungal enzymes, and then mycelia fans spread forming a canker which when it girdles a branch prevents water and nutrient transport, eventually killing the tree above the canker. The fungus does not infect the roots, thus allowing the growth of adventitious shoots to keep the tree alive. However, this survival is only temporary because these spouts will again get infected by the fungus and die back to the ground. It is this continuing circle that made American chestnut, once a great canopy tree, ...
There are few diseases of chestnut trees in North America. However, the one disease chestnut trees have, chestnut blight, is still thought of as one of the worst tree diseases in history.. Chestnut blight has killed more chestnut trees around the world than any other forest disease. The fungus that causes chestnut blight can be traced from China and Japan where it did not cause much disease when compared to North America and Europe where it killed several billion trees. More recently it was found in Australian chestnut orchards and they destroyed several orchards and thousands of trees to hopefully eradicate this disease.. Chestnut blight has the deserved reputation of being impossible to manage when growing chestnut blight-susceptible trees, such as American chestnut. The only species with resistance to the blight fungus are Chinese and Japanese chestnut trees. In Michigan, we primarily grow Chinese trees or European X Japanese hybrid cultivars. While the Chinese trees are chestnut ...
We used (1) ultracentrifugation followed by RT-PCR and (2) real-time RT-PCR to detect and quantify nodaviruses in seawater in which Atlantic halibut Hippoglossus hippoglossus larvae/fry had been held at rearing facilities. Evaluated against in vitro propagated viruses, the viral concentration corresponded to 1.6 × 104 TCID50 (50% tissue culture infectious dose) ml-1. Evaluated against in vitro transcribed RNA, the concentration was estimated at 2 × 107 virus particles ml-1 seawater ...
Mullapudi, E; Fuzik, T; Pridal, A; Plevka, P, 2017: Cryo-electron Microscopy Study of the Genome Release of the Dicistrovirus Israeli Acute Bee Paralysis Virus. JOURNAL OF VIROLOGY 91(4), doi: 10.1128/jvi.02060-16. Research Groups:. ...
The dynamics of viruses are critical to our understanding of disease pathogenesis. Using honey bee Deformed wing virus (DWV) as a model, we conducted field and laboratory studies to investigate the roles of abiotic and biotic stress factors as well as host health conditions in dynamics of virus replication in honey bees. The results showed that temperature decline could lead to not only significant decrease in the rate for pupae to emerge as adult bees, but also an increased severity of the virus infection in emerged bees, partly explaining the high levels of winter losses of managed honey bees, Apis mellifera, around the world. By experimentally exposing adult bees with variable levels of parasitic mite Varroa destructor, we showed that the severity of DWV infection was positively correlated with the density and time period of Varroa mite infestation, confirming the role of Varroa mites in virus transmission and activation in honey bees. Further, we showed that host conditions have a significant impact
Author summary The regulation of type I interferon signaling pathway is dynamic sequential processes and must be tightly regulated to keep balance between antiviral immune and hyper-inflammatory responses. The precise regulation mechanisms of the innate immune signaling pathway are still worth studying. Here, we found a novel role of the interferon-inducible p200 family protein IFI204 that specifically inhibits the IRF7-mediated type I interferon production by negative control of the transcriptional activity of IRF7 in the nucleus at the late stage of RNA virus infection. Previous studies showed that IFI204 is involved in DNA sensing during DNA virus infection to initiate antiviral immune responses. We demonstrate that IFI204 can inhibit IRF7-mediated activation of type I IFN responses induced by RNA virus infection, which is in contrast with its role in IRF3 activation in cGAS-STING DNA sensing pathway during DNA virus infection. Such negative regulation may help to avoid hyper-inflammatory responses

Patrizia FARCI. Hepatitis Delta Virus Hepatitis B surface antigen (HBsAg) HDV RNA genome Hepatitis delta antigen (HDAg) 36 nm...Patrizia FARCI. Hepatitis Delta Virus Hepatitis B surface antigen (HBsAg) HDV RNA genome Hepatitis delta antigen (HDAg) 36 nm...

HDV RNA genome Hepatitis delta antigen (HDAg) 36 nm From HDV: From HBV: From HDV:From HBV: ... Hepatitis Delta Virus Hepatitis B surface antigen (HBsAg) ... 4 Features of the HDV RNA I Transcribed by host RNA Polymerase ... Hepatitis Delta Virus Hepatitis B surface antigen (HBsAg) HDV RNA genome Hepatitis delta antigen (HDAg) 36 nm From HDV: From ... Hepatitis Delta Virus Hepatitis B surface antigen (HBsAg) HDV RNA genome Hepatitis delta antigen (HDAg) 36 nm From HDV: From ...
more infohttp://slideplayer.com/slide/4375152/

THE ROLE OF TOMBUSVIRUS REPLICASE PROTEINS AND RNA IN REPLICASE ASSEMB by Zivile Sliesaraviciute Panaviene"THE ROLE OF TOMBUSVIRUS REPLICASE PROTEINS AND RNA IN REPLICASE ASSEMB" by Zivile Sliesaraviciute Panaviene

... viral RNA replication, subgenomic RNA synthesis and RNA recombination. This data shed new light on the complex roles of the ... their associated DI RNAs, subgenomic (sg)RNA synthesis and DI RNA recombination in vivo. Experiments using a two-component ... Further studies defined RNA motifs within two short DI RNA regions that enhanced active CNV replicase formation. In summary, ... this study showed that the conserved RNA binding motif of the tombusvirus replicase proteins and viral RNA are involved in ...
more infohttps://uknowledge.uky.edu/gradschool_diss/435/

Chinese medicinal herbs for measles | CochraneChinese medicinal herbs for measles | Cochrane

Measles (rubeola) is an infectious disease caused by multiplication of a single-strand ribonucleic acid (RNA) virus of the ...
more infohttp://www.cochrane.org/CD005531/ARI_chinese-medicinal-herbs-for-measles

RNA viruses | PNASRNA viruses | PNAS

Functional conservation despite structural divergence in ligand-responsive RNA switches Mark A. Boerneke, Sergey M. Dibrov, ...
more infohttps://www.pnas.org/keyword/rna-viruses

RNA-virus - WikipediaRNA-virus - Wikipedia

RNA-virus har små og tette genom.[1] RNA-virus benytter RNA-avhengig RNA-polymerase eller revers transkriptase til å kopiere ... RNA-virus er virus som benytter RNA som arvestoff.[1] De benytter organismer fra alle de biologiske rikene som verter.[2] RNA- ... De enkelttråda RNA-virusene kan ha både positiv og negativ RNA-polaritet.[3] RNA-virus er den vanligste klassen av virus som ... og mutasjoner i genoma til RNA-virus blir slik lettere videreførte. Dette bevirker at RNA-virus utvikler seg mye hurtigere enn ...
more infohttps://no.wikipedia.org/wiki/RNA-virus

Double-stranded RNA VirusesDouble-stranded RNA Viruses

... Version 05 February 2006 (temporary). http://tolweb.org/Double-stranded_RNA_Viruses/21833/2006.02. ... Double-stranded RNA Viruses Click on an image to view larger version & data in a new window ... other Viruses. * Double-stranded RNA Viruses * Single-stranded Negative Sense RNA Viruses ... Double-stranded RNA Viruses Branch Page. collections. * Double-stranded RNA Viruses Images ...
more infohttp://tolweb.org/Double-stranded_RNA_Viruses/21833

Mutation rates among RNA viruses | PNASMutation rates among RNA viruses | PNAS

Riboviruses (RNA viruses exclusive of retroviruses) tend to display very high mutation rates (4); however, quantifying those ... Mutation rates among RNA viruses. John W. Drake and John J. Holland ... Bacteriophage φ6 has a segmented, double-stranded RNA genome and thus differs profoundly from the viruses in Table 1. ... A previous analysis of mutation rates in RNA viruses (specifically in riboviruses rather than retroviruses) was constrained by ...
more infohttps://www.pnas.org/content/96/24/13910?ijkey=0dea8efc3f7c64f37d66fd8dd7f16ecc635396cc&keytype2=tf_ipsecsha

Single-stranded Negative Sense RNA VirusesSingle-stranded Negative Sense RNA Viruses

... Click on an image to view larger version & data in a new window ... Arenaviridae are RNA viruses whose particles are spherical and have an average diameter of 110-130 nanometers. Arenaviridae ... Version 05 February 2006 (temporary). http://tolweb.org/Single-stranded_Negative_Sense_RNA_Viruses/21834/2006.02.05 in The Tree ... other Viruses. * Double-stranded RNA Viruses * Single-stranded Negative Sense RNA Viruses ...
more infohttp://www.tolweb.org/Single-stranded_Negative_Sense_RNA_Viruses/21834

RNA Viruses and Lymphocyte Immune Functions | SpringerLinkRNA Viruses and Lymphocyte Immune Functions | SpringerLink

Among the diverse strategies used by viruses to induce human disease, their ability to cause immune defects has received ... Gazzolo L., Dodon M.D., Gessain A., Robert-Guroff M., de-The G. (1985) RNA Viruses and Lymphocyte Immune Functions. In: Gallo R ... Hardy, W.D., Jr., (1984) In Human T-cell leukemia/lymphoma virus, eds. Gallo, R.C., Essex, M.E. & Gross, L. (Cold Spring Harbor ... Among the diverse strategies used by viruses to induce human disease, their ability to cause immune defects has received ...
more infohttps://link.springer.com/chapter/10.1007/978-1-4612-5008-1_31

Single-stranded Positive Sense RNA Viruses ImagesSingle-stranded Positive Sense RNA Viruses Images

Single-stranded Positive Sense RNA Viruses articles & notes. *Single-stranded Positive Sense RNA Viruses Branch Page ... Single-stranded Positive Sense RNA Viruses Images Click on an image to view larger version & data in a new window ... other Viruses. * Double-stranded RNA Viruses * Single-stranded Negative Sense RNA Viruses ... Single-stranded Positive Sense RNA Viruses Movies people. * Single-stranded Positive Sense RNA Viruses People ...
more infohttp://tolweb.org/images/Single-stranded%20Positive%20Sense%20RNA%20Viruses/21835

Neuroviral Infections: RNA Viruses and Retroviruses (Hardback) - RoutledgeNeuroviral Infections: RNA Viruses and Retroviruses (Hardback) - Routledge

Neuroviral Infections: RNA Viruses and Retroviruses presents an… ... Neuroviral Infections: RNA Viruses and Retroviruses presents an up-to-date overview of the general principles of infections and ... Rabies Virus Neurovirulence. Claire L. Jeffries, Ashley C. Banyard, Derek M. Healy, Daniel L. Horton, Nicholas Johnson, and ... major neuroviral infections caused by RNA viruses and retroviruses. It is designed for virologists, specialists in infectious ...
more infohttps://www.routledge.com/Neuroviral-Infections-RNA-Viruses-and-Retroviruses/Singh-Ruzek/p/book/9781466567207

RNA-virus - WikipediaRNA-virus - Wikipedia

RNA-virus er virus som nyttar RNA som arvestoff.[1] Dei nyttar organismar frå alle dei biologiske rika som vertar.[2] RNA-virus ... RNA-virus har småe og tette genom.[1] RNA-virus nyttar RNA-avhengig RNA-polymerase eller revers transkriptase til å kopiera ... Dei enkelttråda RNA-virusa kan ha både positiv og negativ RNA-polaritet.[3] RNA-virus er den vanlegaste klassen av virus som ... og mutasjonar i genoma til RNA-virus vert slik lettare førte vidare. Dette fører til at RNA-virus utviklar seg mykje snøggare ...
more infohttps://nn.wikipedia.org/wiki/RNA-virus

Antivirals against RNA viruses (1639) - SVAAntivirals against RNA viruses (1639) - SVA

Antivirals against RNA viruses. Publicerad 2018-01-15 RNA viruses are highly dependent on host cell machinery to fulfill their ... of RNA virus infections and to develop novel antiviral strategies to battle against several highly pathogenic RNA viruses such ... To date, most of the drugs against viruses act as direct-antivirals, meaning that compounds are designed to directly target ... Direct antivirals are believed to act as highly selective towards specific viruses, however these treatments are often ...
more infohttp://www.sva.se/forskning-och-utveckling/aktuella-forskningsprojekt/antivirals-against-rna-viruses-1639

RNA virus persistence meeting | Universitätsklinikum FreiburgRNA virus persistence meeting | Universitätsklinikum Freiburg

Mechanisms and consequences of RNA virus persistent infections:. It is generally assumed that following acute infection RNA ... RNA virus persistence meeting: mechanisms and consequences August, 23 - 25, 2018, Institute of Virology, Medical Center - ... The purpose of this two-day conference is bringing together scientists working on many different viruses to address and ... discuss underlying general and specific questions concerning the mechanisms and consequences of persistent RNA virus infections ...
more infohttps://www.uniklinik-freiburg.de/rna-virus-persistence.html

Heterosigma akashiwo RNA virus - WikispeciesHeterosigma akashiwo RNA virus - Wikispecies

Regnum: Virus. Group IV: ssRNA(+) Ordo: Picornavirales Familia: Marnaviridae Genus: Marnavirus Species: Heterosigma akashiwo ... Retrieved from "https://species.wikimedia.org/w/index.php?title=Heterosigma_akashiwo_RNA_virus&oldid=6025638" ...
more infohttps://species.wikimedia.org/wiki/Heterosigma_akashiwo_RNA_virus

Keystone Symposia Conference | Positive-Strand RNA Viruses - ProgramKeystone Symposia Conference | Positive-Strand RNA Viruses - Program

Positive-Strand RNA Viruses (E2). Scientific Organizers: Frank van Kuppeveld and Andrea Gamarnik June 9-13, 2019. INEC, ... Rates and Deadlines listed below are for the 2019-E2 "Positive-Strand RNA Viruses" conference only. *All deadlines end at 11:59 ...
more infohttp://www.keystonesymposia.org/index.cfm?e=web.Meeting.Scholarships&meetingid=1649&subTab=scholarships

Medical Xpress - rna virusesMedical Xpress - rna viruses

Related topics: viruses Sorry, no news articles match your request. Your search criteria may be too narrow.. ...
more infohttps://medicalxpress.com/tags/rna+viruses/sort/date/12h/

RNA virus - wikidocRNA virus - wikidoc

Double-stranded RNA viruses. Further information: [[:Double-stranded RNA viruses]]. The double-stranded (ds)RNA viruses ... An RNA virus is a virus that has ribonucleic acid (RNA) as its genetic material and does not replicate using a DNA intermediate ... Although RNA usually mutates rapidly, recent work found that the SARS virus and related RNA viruses contain a gene that mutates ... This means that the virus must bring along with it the RNA-dependent RNA polymerase enzyme. The positive-sense RNA molecule ...
more infohttps://www.wikidoc.org/index.php/RNA_virus

RNA virus - wikidocRNA virus - wikidoc

Double-stranded RNA viruses. Further information: [[:Double-stranded RNA viruses]]. The double-stranded (ds)RNA viruses ... An RNA virus is a virus that has ribonucleic acid (RNA) as its genetic material and does not replicate using a DNA intermediate ... Although RNA usually mutates rapidly, recent work found that the SARS virus and related RNA viruses contain a gene that mutates ... This means that the virus must bring along with it the RNA-dependent RNA polymerase enzyme. The positive-sense RNA molecule ...
more infohttps://www.wikidoc.org/index.php/Positive-sense_ssRNA_virus

Free Laboratory Science Flashcards about RNA VirusesFree Laboratory Science Flashcards about RNA Viruses

RNA Viruses. Micro 701 Exam 1. Envelope present. RNA structure. Envelope Present. RNA structure. Medically Important Viruses. ... Rubella virus. Bunyavirus. helical. Yes. SS circular (-) 3 segments. Hantaan virus, Korean hemorrhagic fever, Lacrosse Fever, ... Yellow Fever virus, dengue virus, Hep C, West Nile. Togavirus. icosahedral. Yes. SS linear, (+) nonsegmented. ...
more infohttps://www.studystack.com/flashcard-88861

Frontiers | ER stress, autophagy, and RNA viruses | MicrobiologyFrontiers | ER stress, autophagy, and RNA viruses | Microbiology

In this review, we summarize the current knowledge about how RNA viruses, including influenza virus, poliovirus, coxsackievirus ... In this review, we summarize the current knowledge about how RNA viruses, including influenza virus, poliovirus, coxsackievirus ... enterovirus 71, Japanese encephalitis virus, hepatitis C virus, and dengue virus, regulate these processes. We also discuss ... enterovirus 71, Japanese encephalitis virus, hepatitis C virus, and dengue virus, regulate these processes. We also discuss ...
more infohttps://www.frontiersin.org/articles/10.3389/fmicb.2014.00388/full

Clonal Interference and the Evolution of RNA Viruses | ScienceClonal Interference and the Evolution of RNA Viruses | Science

The effects of clonal interference were measured in the asexual RNA virus vesicular stomatitis virus; rates and average effects ... RNA viruses show the highest mutation rates in nature (6). This, together with their potentially large effective population ... In this light, how is one to explain the high mutation rates of RNA viruses? When clonal interference is considered, it becomes ... Some have speculated that the high mutation rates of RNA viruses are maintained evolutionarily because of the great adaptive ...
more infohttp://science.sciencemag.org/content/285/5434/1745

RNA Viruses - Videos & Lessons | Study.comRNA Viruses - Videos & Lessons | Study.com

Who hasnt had a cold caused by a virus? Do you know that some viruses are classified as RNA viruses? These viruses have RNA in ... The Ebola Virus and other Deadly Filoviridae Viruses. Examine Filoviridae viruses, like Ebola virus, Marburg virus and ... RNA viruses are the focus of this chapter. Lessons will cover the transmission, structure and life cycles of RNA viruses. Some ... Other RNA Virus Families of Commercial and Zoonotic Importance. Study the rare virus families that are based on RNA. ...
more infohttps://study.com/academy/topic/rna-viruses.html

Order reduction for an RNA virus evolution modelOrder reduction for an RNA virus evolution model

In this paper we conduct the procedure of model order reduction for a reasonably simple model of RNA virus evolution reducing ... Order reduction for an RNA virus evolution model. Andrei Korobeinikov 1, , Aleksei Archibasov 2, and Vladimir Sobolev 3, ... L. S. Tsimring, H. Levine and D. A. Kessler, RNA virus evolution via a fitness-space model,, Phys. Rev. Lett., 76 (1996), 4440 ... L. S. Tsimring, H. Levine and D. A. Kessler, RNA virus evolution via a fitness-space model,, Phys. Rev. Lett., 76 (1996), 4440 ...
more infohttps://aimsciences.org/article/doi/10.3934/mbe.2015.12.1007
  • This comprehensive compilation of the altered gene expression profiles and signal transduction pathways in host cells in response to the majority of human/animal RNA viruses opens new directions for basic and clinical research on viral pathogenesis, and also provides valuable biomarkers for researchers to select gene targets in the development of diagnostic tests and antiviral therapeutics for a number of infectious diseases. (whsmith.co.uk)
  • Animal RNA viruses are classified by the ICTV. (wikipedia.org)
  • DNA damage can contribute to the pathogenesis of RNA viruses through the triggering of apoptosis, stimulation of inflammatory immune responses and the introduction of deleterious mutations that can increase the risk of tumorigenesis. (mdpi.com)
  • In recent years the increasing knowledge of virus particle assembly, virus-cell interactions, and viral pathogenesis allow approaches for the development of novel antiviral strategies or agents. (wikipedia.org)
  • De med positiv polaritet kan oversette RNA-molekylet sitt direkte til protein, mens de med negativ polaritet først må skrive det av til budbærer-RNA før de kan omsette det til protein . (wikipedia.org)
  • Dei med positiv polaritet kan setja om RNA-molekylet sitt direkte til protein , medan dei med negativ polaritet fyrst lyt skriva det av til bodberar-RNA før dei kan setja det om til protein. (wikipedia.org)
  • These in silico primers are capable of detecting 100% of the RNA viruses included in the latest U.S National Center for Biotechnology Information Reference Sequence (NCBI RefSeq) database, an open access curated collection of DNA and RNA nucleotide sequences and their protein products. (news-medical.net)
  • RNA viruses generally have very high mutation rates as they lack DNA polymerases which can find and fix mistakes, and are therefore unable to conduct DNA repair of damaged genetic material. (wikidoc.org)
  • A virus consists of genetic material, which may be either DNA or RNA, and is surrounded by a protein coat and, in some viruses, by a membranous envelope. (thefreedictionary.com)
  • Within the host cell the genetic material of a DNA virus is replicated and transcribed into messenger RNA by host cell enzymes, and proteins coded for by viral genes are synthesized by host cell ribosomes. (thefreedictionary.com)
  • 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)
  • Over the last two decades it has become increasingly clear that many RNA viruses add the capacity to exchange genetic material with one another, and to acquire genes from their hosts, to this evolutionary repertoire. (biology-online.org)
  • and (iv) the small interfering RNA/microRNA-mediated gene silencing pathway, a recently characterized new host defense mechanism against viral infection.Organized into 27 highly accessible and well-illustrated chapters, this volume explores state-of-the-art knowledge of the molecular mechanisms of RNA virus infection and host-virus interactions. (whsmith.co.uk)
  • The double-stranded (ds)RNA viruses represent a diverse group of viruses that vary widely in host range (humans, animals, plants, fungi , and bacteria ), genome segment number (one to twelve), and virion organization (T-number, capsid layers, or turrets). (wikidoc.org)
  • Some viruses have only a few genes coding for capsid proteins. (thefreedictionary.com)
  • A distinguishing feature of the dsRNA viruses, irrespective of their family association, is their ability to carry out transcription of the dsRNA segments, under appropriate conditions, within the capsid. (wikipedia.org)
  • CPV exhibits striking capsid stability and is fully capable of endogenous RNA transcription and processing. (wikipedia.org)
  • One of these includes RNA replicase , which copies the viral RNA to form a double-stranded replicative form, in turn this directs the formation of new virions. (wikidoc.org)
  • In turn this dsRNA directs the formation of new viral RNA. (wikipedia.org)
  • The 3 sequences cluster with Mobala virus (80% bootstrap support), an arenavirus discovered in Praomys sp. (thefreelibrary.com)
  • The new DGIST reference resource, the MTPrimerV database, contains 152, 380, 247 PCR primer pairs for the detection of 1,818 viruses, covering 7,144 gene-coding sequences or CDSs (from coding DNA sequence), which are the portion of a gene's DNA or RNA that codes for a protein. (news-medical.net)
  • hybrid sequences resulting from aberrant homologous recombination (when similar viruses exchange sequence without maintaining strict alignment) and nonhomologous recombination (recombination between unrelated RNA sequences) are also commonly observed (Lai, 1992). (biology-online.org)
  • In this paper we conduct the procedure of model order reduction for a reasonably simple model of RNA virus evolution reducing the original system of three integro-partial derivative equations to a single equation. (aimsciences.org)
  • It is generally assumed that following acute infection RNA viruses are effectively cleared by the immune system. (uniklinik-freiburg.de)
  • Establishing persistent infection likely involves a number of molecular, cellular and immunological determinants, including the genetics of the viruses, the genetics of their hosts and potential new host species, and many environmental factors, such as other microorganisms. (uniklinik-freiburg.de)
  • As such, purified RNA of a positive-sense virus can directly cause infection though it may be less infectious than the whole virus particle. (wikidoc.org)
  • Double-Stranded RNA Virus: Host Signaling Responses to Reovirus Infection (D Pan et al. (whsmith.co.uk)
  • Although RNA usually mutates rapidly, recent work found that the SARS virus and related RNA viruses contain a gene that mutates very slowly. (wikidoc.org)
  • In recent years, new and fatal diseases due to RNA viruses have emerged, notably severe acute respiratory syndrome (SARS) and Middle East respiratory disease (MERS), both of which had severe health and economic impacts. (news-medical.net)
  • Take a look at viruses in the Bunyaviridae family. (study.com)
  • Hantaviruses (family Bunyaviridae) are RNA viruses primarily carried by rodents and soricomorphs (shrews and moles), although 2 new species have recently been described in bats (2,3). (thefreelibrary.com)
  • Members of both genera can cause life-threatening diseases in humans: arena-viruses cause hemorrhagic fevers in the Americas and Africa, and hantaviruses cause hemorrhagic fever with renal syndrome in Asia and Europe and hantavirus cardiopulmonary syndrome in the Americas. (thefreelibrary.com)
  • This is one reason why it is difficult to make effective vaccines to prevent diseases caused by RNA viruses. (wikipedia.org)
  • The International Committee on Taxonomy of Viruses (ICTV) classifies RNA viruses as those that belong to Group III, Group IV or Group V of the Baltimore classification system of classifying viruses and does not consider viruses with DNA intermediates in their life cycle as RNA viruses. (wikipedia.org)
  • The synanthropic nature of some rodent species makes them important reservoirs of RNA viruses pathogenic to humans, such as hantaviruses (e.g. (thefreelibrary.com)
  • Numerous viruses introduce DNA damage and genetic instability in host cells during their lifecycles and some species also manipulate components of the DNA damage response (DDR), a complex and sophisticated series of cellular pathways that have evolved to detect and repair DNA lesions. (mdpi.com)
  • Families Amalgaviridae Birnaviridae Chrysoviridae Cystoviridae Endornaviridae Hypoviridae Megabirnaviridae Partitiviridae Picobirnaviridae Quadriviridae Reoviridae Totiviridae Unassigned species La France isometric virus Reoviridae are currently classified into nine genera. (wikipedia.org)
  • Among the diverse strategies used by viruses to induce human disease, their ability to cause immune defects has received increasing attention, concurrently with the identification of cells able to mount a large variety of immune responses and secrete numerous factors modulating these responses. (springer.com)
  • Discover the virus family that includes equine encephalitis, rubella and German measles. (study.com)
  • The orthoreoviruses (reoviruses) are the prototypic members of the virus Reoviridae family and representative of the turreted members, which comprise about half the genera. (wikipedia.org)
  • A cell is infected with one (or more) virus particles. (pnas.org)
  • M. A. Nowak and R. M. May, Virus dynamics: Mathematical principles of Immunology and Virology ,, Oxford University Press , (2000). (aimsciences.org)