Mosaic Viruses: Viruses which produce a mottled appearance of the leaves of plants.Cucumovirus: A genus of plant viruses of the family BROMOVIRIDAE, which infect cucurbits and solanaceous plants. Transmission occurs via aphids in a non-persistent manner, and also via seeds. The type species Cucumber mosaic virus, a CUCUMOVIRUS, should not be confused with Cucumber green mottle mosaic virus, a TOBAMOVIRUS.Tobacco: A plant genus of the family SOLANACEAE. Members contain NICOTINE and other biologically active chemicals; its dried leaves are used for SMOKING.Caulimovirus: A genus of PLANT VIRUSES, in the family CAULIMOVIRIDAE, that are transmitted by APHIDS in a semipersistent manner. Aphid-borne transmission of some caulimoviruses requires certain virus-coded proteins termed transmission factors.Comovirus: A genus of plant viruses of the family COMOVIRIDAE in which the bipartite genome is encapsidated in separate icosahedral particles. Mosaic and mottle symptoms are characteristic, and transmission is exclusively by leaf-feeding beetles. Cowpea mosaic virus is the type species.Tobacco Mosaic Virus: The type species of TOBAMOVIRUS which causes mosaic disease of tobacco. Transmission occurs by mechanical inoculation.Plant Diseases: Diseases of plants.Plants, Toxic: Plants or plant parts which are harmful to man or other animals.Plant Viruses: Viruses parasitic on plants higher than bacteria.RNA, Viral: Ribonucleic acid that makes up the genetic material of viruses.Plant Viral Movement Proteins: Viral proteins that facilitate the movement of viruses between plant cells by means of PLASMODESMATA, channels that traverse the plant cell walls.Bromovirus: A genus of tripartite plant viruses in the family BROMOVIRIDAE. Transmission is by beetles. Brome mosaic virus is the type species.RNA Viruses: Viruses whose genetic material is RNA.Viral Proteins: Proteins found in any species of virus.Tymovirus: A genus of plant viruses, in the family TYMOVIRIDAE, possessing a narrow host range that includes CRUCIFERAE. Transmission occurs by BEETLES and mechanical inoculation.Protoplasts: The protoplasm and plasma membrane of plant, fungal, bacterial or archaeon cells without the CELL WALL.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.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.Potexvirus: A genus of plant viruses in the family FLEXIVIRIDAE, that cause mosaic and ringspot symptoms. Transmission occurs mechanically. Potato virus X is the type species.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.Capsid: The outer protein protective shell of a virus, which protects the viral nucleic acid.Cucumber Mosaic Virus Satellite: A satellite RNA (not a satellite virus) which has several types. Different cucumoviruses can act as helper viruses for different types.Plants, Genetically Modified: PLANTS, or their progeny, whose GENOME has been altered by GENETIC ENGINEERING.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.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)Plant Leaves: Expanded structures, usually green, of vascular plants, characteristically consisting of a bladelike expansion attached to a stem, and functioning as the principal organ of photosynthesis and transpiration. (American Heritage Dictionary, 2d ed)Virus Assembly: The assembly of VIRAL STRUCTURAL PROTEINS and nucleic acid (VIRAL DNA or VIRAL RNA) to form a VIRUS PARTICLE.Capsid Proteins: Proteins that form the CAPSID of VIRUSES.Potyviridae: A family of RNA plant viruses with flexuous, filamentous particles and consisting of six genera: POTYVIRUS; Ipomovirus; Macluravirus; Rymovirus; Tritimovirus; and Bymovirus. All members of the family form cytoplasmic cylindrical inclusion bodies during infection.Chenopodium quinoa: A species of the Chenopodium genus which is the source of edible seed called quinoa. It contains makisterone A and other STEROIDS, some having ECDYSTEROID activity on insects.Mosaicism: The occurrence in an individual of two or more cell populations of different chromosomal constitutions, derived from a single ZYGOTE, as opposed to CHIMERISM in which the different cell populations are derived from more than one zygote.Genes, Viral: The functional hereditary units of VIRUSES.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.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)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.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.Manihot: A plant genus of the family EUPHORBIACEAE that is perennial with conspicuous, almost palmate leaves like those of RICINUS but more deeply parted into five to nine lobes. It is a source of a starch after removal of the cyanogenic glucosides. The common name of Arrowroot is also used with Maranta (MARANTACEAE). The common name of yuca is also used for YUCCA.Virus Cultivation: Process of growing viruses in live animals, plants, or cultured cells.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.Virus Diseases: A general term for diseases produced by 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).Geminiviridae: A family of plant viruses where the VIRION possesses an unusual morphology consisting of a pair of isometric particles. Transmission occurs via leafhoppers or whitefly. Some viruses cause economically important diseases in cultivated plants. There are four genera: Mastrevirus, Curtovirus, Topocuvirus, and BEGOMOVIRUS.DNA, Viral: Deoxyribonucleic acid that makes up the genetic material of viruses.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.Brassica: A plant genus of the family Cruciferae. It contains many species and cultivars used as food including cabbage, cauliflower, broccoli, Brussel sprouts, kale, collard greens, MUSTARD PLANT; (B. alba, B. junica, and B. nigra), turnips (BRASSICA NAPUS) and rapeseed (BRASSICA RAPA).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.Sasa: A plant genus of the family POACEAE. Folin is the water-soluble extract from Sasa albomarginata. Sasa kurinensis is an ingredient of Sho-ju-sen, a Japanese herbal medicine.Hordeum: A plant genus of the family POACEAE. The EDIBLE GRAIN, barley, is widely used as food.DNA Viruses: Viruses whose nucleic acid is DNA.Cucurbita: A plant genus of the family CUCURBITACEAE, order Violales, subclass Dilleniidae, which includes pumpkin, gourd and squash.Fabaceae: The large family of plants characterized by pods. Some are edible and some cause LATHYRISM or FAVISM and other forms of poisoning. Other species yield useful materials like gums from ACACIA and various LECTINS like PHYTOHEMAGGLUTININS from PHASEOLUS. Many of them harbor NITROGEN FIXATION bacteria on their roots. Many but not all species of "beans" belong to this family.Aphids: A family (Aphididae) of small insects, in the suborder Sternorrhyncha, that suck the juices of plants. Important genera include Schizaphis and Myzus. The latter is known to carry more than 100 virus diseases between plants.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).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.Alfalfa mosaic virus: The type species of the genus ALFAMOVIRUS that is non-persistently transmitted by aphids.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.Measles virus: The type species of MORBILLIVIRUS and the cause of the highly infectious human disease MEASLES, which affects mostly children.Plants: Multicellular, eukaryotic life forms of kingdom Plantae (sensu lato), comprising the VIRIDIPLANTAE; RHODOPHYTA; and GLAUCOPHYTA; all of which acquired chloroplasts by direct endosymbiosis of CYANOBACTERIA. They are characterized by a mainly photosynthetic mode of nutrition; essentially unlimited growth at localized regions of cell divisions (MERISTEMS); cellulose within cells providing rigidity; the absence of organs of locomotion; absence of nervous and sensory systems; and an alternation of haploid and diploid generations.Panicum: A plant genus of the family POACEAE. The seed is one of the EDIBLE GRAINS used in millet cereals and in feed for birds and livestock (ANIMAL FEED). It contains diosgenin (SAPONINS).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.Tobacco mosaic satellite virus: A spherical RNA satellite virus which requires an obligatory helper TOBACCO MOSAIC VIRUS for replication.Gene Expression Regulation, Viral: Any of the processes by which cytoplasmic factors influence the differential control of gene action in viruses.Begomovirus: A genus of plant viruses in the family GEMINIVIRIDAE that are transmitted in nature by whitefly Bemisia tabaci.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.Nucleic Acid Conformation: The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.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.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.Lycopersicon esculentum: A plant species of the family SOLANACEAE, native of South America, widely cultivated for their edible, fleshy, usually red fruit.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Genome, Viral: The complete genetic complement contained in a DNA or RNA molecule in a virus.Plant Proteins: Proteins found in plants (flowers, herbs, shrubs, trees, etc.). The concept does not include proteins found in vegetables for which VEGETABLE PROTEINS is available.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.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.Medicago sativa: A plant species of the family FABACEAE widely cultivated for ANIMAL FEED.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.Plants, Medicinal: Plants whose roots, leaves, seeds, bark, or other constituent parts possess therapeutic, tonic, purgative, curative or other pharmacologic attributes, when administered to man or animals.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.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.Antigens, Viral: Substances elaborated by viruses that have antigenic activity.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.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.Host-Pathogen Interactions: The interactions between a host and a pathogen, usually resulting in disease.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).Triticum: A plant genus of the family POACEAE that is the source of EDIBLE GRAIN. A hybrid with rye (SECALE CEREALE) is called TRITICALE. The seed is ground into FLOUR and used to make BREAD, and is the source of WHEAT GERM AGGLUTININS.Citrullus: A plant genus of the family CUCURBITACEAE known for the edible fruit.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Cucumis sativus: A creeping annual plant species of the CUCURBITACEAE family. It has a rough succulent, trailing stem and hairy leaves with three to five pointed lobes.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.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.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.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.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.Malvaceae: The mallow family of the order Malvales, subclass Dilleniidae, class Magnoliopsida. Members include GOSSYPIUM, okra (ABELMOSCHUS), HIBISCUS, and CACAO. The common names of hollyhock and mallow are used for several genera of Malvaceae.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.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Oncogenic Viruses: Viruses that produce tumors.Ilarvirus: A genus of the family BROMOVIRIDAE which infects mainly woody plants. Species are divided into ten subgroups. Tobacco streak virus is the type species.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.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.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.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.Arabidopsis: A plant genus of the family BRASSICACEAE that contains ARABIDOPSIS PROTEINS and MADS DOMAIN PROTEINS. The species A. thaliana is used for experiments in classical plant genetics as well as molecular genetic studies in plant physiology, biochemistry, and development.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.Green Fluorescent Proteins: Protein analogs and derivatives of the Aequorea victoria green fluorescent protein that emit light (FLUORESCENCE) when excited with ULTRAVIOLET RAYS. They are used in REPORTER GENES in doing GENETIC TECHNIQUES. Numerous mutants have been made to emit other colors or be sensitive to pH.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.Gene Expression Regulation, Plant: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in plants.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.Genes, Plant: The functional hereditary units of PLANTS.Mumps virus: The type species of RUBULAVIRUS that causes an acute infectious disease in humans, affecting mainly children. Transmission occurs by droplet infection.Salicylic Acid: A compound obtained from the bark of the white willow and wintergreen leaves. It has bacteriostatic, fungicidal, and keratolytic actions.Parainfluenza Virus 1, Human: A species of RESPIROVIRUS also called hemadsorption virus 2 (HA2), which causes laryngotracheitis in humans, especially children.Plasmodesmata: Membrane-like channels of cytoplasm connecting adjacent plant cells. Plasmodesmata connect through pores in the CELL WALL and associate with the CYTOSKELETON machinery. They are essential for intercellular transport and communication.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.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.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.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.Semliki forest virus: A species of ALPHAVIRUS isolated in central, eastern, and southern Africa.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.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Avian Sarcoma Viruses: Group of alpharetroviruses (ALPHARETROVIRUS) producing sarcomata and other tumors in chickens and other fowl and also in pigeons, ducks, and RATS.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.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.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).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.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.Sequence Deletion: Deletion of sequences of nucleic acids from the genetic material of an individual.Inclusion Bodies, Viral: An area showing altered staining behavior in the nucleus or cytoplasm of a virus-infected cell. Some inclusion bodies represent "virus factories" in which viral nucleic acid or protein is being synthesized; others are merely artifacts of fixation and staining. One example, Negri bodies, are found in the cytoplasm or processes of nerve cells in animals that have died from rabies.Nepovirus: A genus of polyhedral plant viruses of the family COMOVIRIDAE causing ringspots and spotting on leaves or sometimes symptomless infection. Transmission occurs by seeds, soil nematodes, or experimentally by mechanical inoculation. Tobacco ringspot virus is the type species.Carica: A plant genus of the family Caricaceae, order Violales, subclass Dilleniidae, class Magnoliopsida. It is the source of edible fruit and PAPAIN.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.Genetic Variation: Genotypic differences observed among individuals in a population.Viruses, Unclassified: Viruses whose taxonomic relationships have not been established.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.Helper Viruses: Viruses which enable defective viruses to replicate or to form a protein coat by complementing the missing gene function of the defective (satellite) virus. Helper and satellite may be of the same or different genus.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.Avian leukosis virus: The type species of ALPHARETROVIRUS producing latent or manifest lymphoid leukosis in fowl.3' Untranslated Regions: The sequence at the 3' end of messenger RNA that does not code for product. This region contains transcription and translation regulating sequences.Transformation, Genetic: Change brought about to an organisms genetic composition by unidirectional transfer (TRANSFECTION; TRANSDUCTION, GENETIC; CONJUGATION, GENETIC, etc.) and incorporation of foreign DNA into prokaryotic or eukaryotic cells by recombination of part or all of that DNA into the cell's genome.Sesbania: A plant genus of the family FABACEAE. Members contain piperidine alkaloids (PIPERIDINES).Mutagenesis, Site-Directed: Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.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.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.Tobamovirus: A genus of plant viruses in which the virion is a rigid filament. Transmission is by mechanical inoculation or seed. The type species is TOBACCO MOSAIC VIRUS.Soybeans: An annual legume. The SEEDS of this plant are edible and used to produce a variety of SOY FOODS.Orthomyxoviridae Infections: Virus diseases caused by the ORTHOMYXOVIRIDAE.Disease Resistance: The capacity of an organism to defend itself against pathological processes or the agents of those processes. This most often involves innate immunity whereby the organism responds to pathogens in a generic way. The term disease resistance is used most frequently when referring to plants.Trifolium: A plant genus of the family FABACEAE.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.Alfamovirus: A genus of the family BROMOVIRIDAE with a wide host range. Transmission is by aphids and the type species is ALFALFA MOSAIC VIRUS.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.Mutagenesis: Process of generating a genetic MUTATION. It may occur spontaneously or be induced by MUTAGENS.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.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.GlucuronidaseProtein 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.Luminescent Proteins: Proteins which are involved in the phenomenon of light emission in living systems. Included are the "enzymatic" and "non-enzymatic" types of system with or without the presence of oxygen or co-factors.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.Yellow fever virus: The type species of the FLAVIVIRUS genus. Principal vector transmission to humans is by AEDES spp. mosquitoes.Brassica napus: A plant species of the family BRASSICACEAE best known for the edible roots.Immunity, Innate: The capacity of a normal organism to remain unaffected by microorganisms and their toxins. It results from the presence of naturally occurring ANTI-INFECTIVE AGENTS, constitutional factors such as BODY TEMPERATURE and immediate acting immune cells such as NATURAL KILLER CELLS.Simplexvirus: A genus of the family HERPESVIRIDAE, subfamily ALPHAHERPESVIRINAE, consisting of herpes simplex-like viruses. The type species is HERPESVIRUS 1, HUMAN.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.Luteoviridae: A family of RNA plant viruses infecting disparate plant families. They are transmitted by specific aphid vectors. There are three genera: LUTEOVIRUS; Polerovirus; and Enamovirus.Luteovirus: A genus of plant viruses that infects both monocotyledonous and dicotyledonous plants. Its organisms are persistently transmitted by aphids, and weeds may provide reservoirs of infection.Antibodies, Viral: Immunoglobulins produced in response to VIRAL ANTIGENS.RNA, Plant: Ribonucleic acid in plants having regulatory and catalytic roles as well as involvement in protein synthesis.Recombinant Proteins: Proteins prepared by recombinant DNA technology.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.Myxoma virus: The type species of LEPORIPOXVIRUS causing infectious myxomatosis, a severe generalized disease, in rabbits. Tumors are not always present.Capsicum: A plant genus of the family SOLANACEAE. The hot peppers yield CAPSAICIN, which activates VANILLOID RECEPTORS. Several varieties have sweet or pungent edible fruits that are used as vegetables when fresh and spices when the pods are dried.Amino Acid Substitution: The naturally occurring or experimentally induced replacement of one or more AMINO ACIDS in a protein with another. If a functionally equivalent amino acid is substituted, the protein may retain wild-type activity. Substitution may also diminish, enhance, or eliminate protein function. Experimentally induced substitution is often used to study enzyme activities and binding site properties.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.Cowpox virus: A species of ORTHOPOXVIRUS that is the etiologic agent of COWPOX. It is closely related to but antigenically different from VACCINIA VIRUS.DNA, Complementary: Single-stranded complementary DNA synthesized from an RNA template by the action of RNA-dependent DNA polymerase. cDNA (i.e., complementary DNA, not circular DNA, not C-DNA) is used in a variety of molecular cloning experiments as well as serving as a specific hybridization probe.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.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.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.Cucumis melo: A plant species of the family CUCURBITACEAE, order Violales, subclass Dilleniidae known for the melon fruits with reticulated (net) surface including cantaloupes, honeydew, casaba, and Persian melons.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.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.Chenopodiaceae: The goosefoot plant family of the order Caryophyllales, subclass Caryophyllidae, class Magnoliopsida. It includes beets and chard (BETA VULGARIS), as well as SPINACH, and salt tolerant plants.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.Brassica rapa: A plant species cultivated for the seed used as animal feed and as a source of canola cooking oil.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.RNA Helicases: A family of proteins that promote unwinding of RNA during splicing and translation.Agrobacterium tumefaciens: A species of gram-negative, aerobic bacteria isolated from soil and the stems, leafs, and roots of plants. Some biotypes are pathogenic and cause the formation of PLANT TUMORS in a wide variety of higher plants. The species is a major research tool in biotechnology.Chikungunya virus: A species of ALPHAVIRUS causing an acute dengue-like fever.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.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)Restriction Mapping: Use of restriction endonucleases to analyze and generate a physical map of genomes, genes, or other segments of DNA.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.Chimera: An individual that contains cell populations derived from different zygotes.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.Codon: A set of three nucleotides in a protein coding sequence that specifies individual amino acids or a termination signal (CODON, TERMINATOR). Most codons are universal, but some organisms do not produce the transfer RNAs (RNA, TRANSFER) complementary to all codons. These codons are referred to as unassigned codons (CODONS, NONSENSE).Sequence Homology: The degree of similarity between sequences. Studies of AMINO ACID SEQUENCE HOMOLOGY and NUCLEIC ACID SEQUENCE HOMOLOGY provide useful information about the genetic relatedness of genes, gene products, and species.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.Gene Silencing: Interruption or suppression of the expression of a gene at transcriptional or translational levels.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.DNA Virus Infections

Physical and functional heterogeneity in TYMV RNA: evidence for the existence of an independent messenger coding for coat protein. (1/667)

Turnip yellow mosaic virus RNA can be separated into two distinct components of 2 times 10(6) and 300 000 daltons molecular weight after moderate heat treatment in the presence of SDS or EDTA. The two species cannot have arisen by accidental in vitro degradation of a larger RNA, as they both possess capped 5' ends. Analysis of the newly synthesized proteins resulting from translation of each RNA by a wheat germ extract shows that the 300 000 molecular weight RNA can be translated very efficiently into coat protein. When translated in vitro the longer RNA gave a series of high molecular weight polypeptides but only very small amounts of a polypeptide having about the same mass as the coat protein. Thus our results suggest that the small RNA is the functional messenger for coat protein synthesis in infected cells.  (+info)

Complete sequence and genome properties of Chinese wheat mosaic virus, a new furovirus from China. (2/667)

The complete nucleotide sequence of a virus infecting winter wheat in Shandong province, China has been determined. This was previously thought to be soil-borne wheat mosaic virus but, while the two viruses are related, they are only 75% (RNA1) and 63% (RNA2) identical at the nucleotide level, while the amino acid sequences share from 62% (19 kDa RNA2 product) to 84% (RNA1 replicase) identity. The analysis shows that the Chinese virus should be considered a new member of the genus Furovirus and has been named Chinese wheat mosaic virus (CWMV). A Cys-Gly ... Cys-Gly-X-X-His amino acid pattern was identified in the cysteine-rich protein of CWMV and those of several other plant virus genera, which seems likely to have some functional significance.  (+info)

The sCYMV1 hairpin ribozyme: targeting rules and cleavage of heterologous RNA. (3/667)

The catalytic center of the RNA from the negative strand of the satellite RNA of chicory yellow mottle virus type 1 (sCYMV1) is in the hairpin ribozyme family, has catalytic activity, and cleaves substrates before a preferred GUA sequence. This is different from that of the satellite RNA from the negative strand of tobacco ringspot virus (sTRSV) which prefers a GUC sequence at the site of cleavage. The sCYMV1 hairpin ribozyme has now been developed for cleaving heterologous RNA substrates. When helix 1 was extended from the native 5 bp to 6 bp with a newly added A:U base pair, catalytic activity increased three-fold. The preferred sequence for the substrate loop was the native A*GUA sequence where * is the site of cleavage. When each nucleotide in this sequence was changed to each of the other three nucleotides, catalytic activity decreased 66-100%. RNA targets, containing this A*GUA sequence, were located in both human papillomavirus and HIV-1. Ribozymes were developed which efficiently cleaved these targets in vitro. These results identify a new class of hairpin ribozymes capable of cleaving substrates before a preferred GUA sequence rather than the GUC preferred by the sTRSV hairpin ribozyme. This expands the repertoire of target sites available for gene therapy using the hairpin ribozyme.  (+info)

Rapid generation of genetic heterogeneity in progenies from individual cDNA clones of peach latent mosaic viroid in its natural host. (4/667)

Viroids, small single-stranded circular RNAs endowed with autonomous replication, are unique systems to conduct evolutionary studies of complete RNA genomes. The primary structure of 36 progeny variants of peach latent mosaic viroid (PLMVd), evolved from inoculations of the peach indicator GF-305 with four individual PLMVd cDNAs differing in their pathogenicity, has been determined. Most progeny variants had unique sequences, revealing that the extremely heterogeneous character of PLMVd natural isolates most probably results from the intrinsic ability of this RNA to accumulate changes, rather than from repeated inoculations of the same individual trees under field conditions. The structure of the populations derived from single PLMVd sequences differed according to the observed phenotype. Variant gds6 induced a reproducible symptomatic infection and gave rise to a more uniform progeny that preserves some parental features, whereas variant gds15, which induced a variable phenotype, showed a more complex behaviour, generating two distinct progenies in symptomatic and asymptomatic individual plants. Progenies derived from variants esc10 and Is11, which incited latent infections, followed a similar evolutionary pattern, leading to a population structure consisting of two main groups of variants, one of which was formed by variants closely related to the parental sequence. The evolution rate exhibited by PLMVd, considerably higher than that reported for potato spindle tuber viroid, may contribute to the fluctuating symptomatology of the severe PLMVd natural isolates. However, the polymorphism observed in PLMVd progenies does preserve some structural and functional elements previously proposed for this viroid, supporting the fact that they act as constraints limiting the genetic divergence of PLMVd quasispecies generated de novo.  (+info)

Sequences of European wheat mosaic virus and oat golden stripe virus and genome analysis of the genus furovirus. (5/667)

The complete nucleotide sequences of both RNAs of oat golden stripe virus (OGSV) and a wheat-infecting furovirus isolate from France, previously thought to be soil-borne wheat mosaic virus (SBWMV), have been determined. Both viruses had a similar genomic organisation to SBWMV and Chinese wheat mosaic virus, the two other furoviruses previously sequenced but had <70% nucleotides identical to them. The French isolate has been named European wheat mosaic virus (EWMV). Phylogenetic analyses supported the recognition of these isolates as distinct viruses in the genus Furovirus. Analysis of the coat protein readthrough domain on RNA2 of all furoviruses strongly predicts two mutually compatible conserved transmembrane domains that may be significant for fungus transmission. The second of these regions is eliminated by a deletion in the isolate of OGSV studied. Leaky opal (UGA) stop codons occur on both RNAs of all four furoviruses characterised and, in common with most other leaky opal codons identified in plant viruses, they are followed by a CGG codon.  (+info)

Structural fingerprinting: subgrouping of comoviruses by structural studies of red clover mottle virus to 2.4-A resolution and comparisons with other comoviruses. (6/667)

Red clover mottle virus (RCMV) is a member of the comoviruses, a group of picornavirus-like plant viruses. The X-ray structure of RCMV strain S has been determined and refined to 2.4 A. The overall structure of RCMV is similar to that of two other comoviruses, Cowpea mosaic virus (CPMV) and Bean pod mottle virus (BPMV). The sequence of the coat proteins of RCMV strain O were modeled into the capsid structure of strain S without causing any distortion, confirming the close resemblance between the two strains. By comparing the RCMV structure with that of other comoviruses, a structural fingerprint at the N terminus of the small subunit was identified which allowed subgrouping of comoviruses into CPMV-like and BPMV-like viruses.  (+info)

Quasi-elastic behavior of solutions of viral capsid and RNA at very low shearing stresses. (7/667)

By the application of shearing stresses on the order of 10(-3) dyne cm-2 (10(-2) muN cm-2), via the magnetic viscodensimeter, extremely high relative viscosities (greater than 500) were observed when turnip yellow mosaic virus was degraded in alkali into its capsid and RNA. The solutions, however, possessed a watery consistency at this stage and exhibited a quasi-elastic character by rotor-recoil experiments. The development of this curious behavior was concentration and temperature dependent; it was not seen less than 0.5% nor at 8 degrees, and appeared sooner at 30 degrees than at 20 degrees. The time of appearance was delayed as the pH was lowered; however, the effect was still observed when the pH was as low as 9. Whereas reversibility was demonstrated when the shearing stresses exceeded the elastic resistance [0.17 dyne cm-2 (1.7 muN CM-2)], thorough mixing usually resulted in a normal behavior of the solutions thereafter. Values for the modulus of rigidity at 20 degrees for about 1% virus concentration was less than 2 X 10(-2) dyne cm-2 rad-1 (0.2 muN cm-2 rad-1), which, while extremely small, was reproducible. A porous structure, possibly involving a capsid and RNA complex, is envisioned.  (+info)

A gene cluster encoded by panicum mosaic virus is associated with virus movement. (8/667)

A subgenomic RNA (sgRNA) of about 1500 nucleotides has been detected in millet plants and protoplasts infected with panicum mosaic virus (PMV). This sgRNA expressed p8, p6.6, p15, and the 26-kDa capsid protein (CP) genes during in vitro translation assays, as determined by using mutants inactivated for expression of each open reading frame. Abolishing expression of p8 and p6.6, the two 5'-proximal genes on the sgRNA, did not affect the replication of PMV in millet protoplasts, but obstructed spread in plants. As predicted for a typical cell-to-cell movement protein, p8 localized to the cell wall fraction of PMV-infected millet plants. The introduction of premature stop codons downstream of the PMV p15 start codon (p15*) abolished infectivity in planta, but did not impair replication in protoplasts. However, a delayed systemic infection in millet plants was supported by the p15aug(-) start codon mutant, which may reflect very low levels of expression from a suboptimal start codon context and/or leaky scanning to a second inframe AUG codon to express the C-terminal portion of the 15-kDa protein. PMV CP mutants had little effect on sgRNA accumulation, but were correlated with a reduction of the gRNA and the decreased expression of the 8-kDa protein in protoplasts as well as abolishment of cell-to-cell spread in plants. These results imply that the successful establishment of a PMV systemic infection in millet host plants appears to be dependent on the concerted expression of the p8, p6.6, p15, and CP genes.  (+info)

  • During the 1930s attenuated rinderpest vaccines were developed by passage of the virus in nonnatural hosts, e.g. rabbit and embryonated eggs (lapinized avian-ized) or goats (caprinized). (centrallakesclinic.biz)
  • Leaves that are distorted by the virus cannot function normally, so plants stop gaining size and may produce dense clusters of infertile flowers. (growveg.co.uk)
  • During the eradication campaign, most smallpox vaccines (vaccinia virus) had a level of side effects which made them unacceptable for current use. (centrallakesclinic.biz)
  • Alfalfa mosaic virus (AlMV) RNAs 1 and 2 with deletions in their 3′ non‑translated regions (NTRs) have been previously shown to be encapsidated into virions by coat protein (CP) expressed from RNA3, indicating that the 3′ NTRs of RNAs 1 and 2 are not required for virion assembly. (mdpi.com)
  • The topic of my research is the Cauliflower Mosaic Virus (CaMV). (kenyon.edu)
  • Cauliflower Mosaic Virus (CaMV), specifically, effects the Brassicaceae family and impacts a host range including crops such as broccoli, cabbage, cauliflower and turnips.Cauliflower mosaic virus is classified as a Group VII. (kenyon.edu)
  • Recently researchers from the John Innes Centre (JIC) for plant research in Great Britain have again claimed that the Cauliflower Mosaic Virus (CaMV) promoter used to genetically modify virtually all of the transgenic crops now marketed or being tested for marketing has been proven to be safe for human consumption because humans have been consuming virus infected crucifers for a long time. (i-sis.org.uk)
  • Even if virus infected crucifers could be prepared and consumed as dietary treats the fact is that the behavior and potential hazard of the CaMV promoter in transgenic crops is unrelated to the replication and behavior of the virus in the plant cell. (i-sis.org.uk)
  • It is simply unreasonable to maintain that the the integrated CaMV promoter in transgenic crops behaves the same way in the virus replication cycle as it does in the chromosome of the transgenic crop. (i-sis.org.uk)
  • CaMV is a pararetrovirus which means that it transmitted as a double stranded DNA virus that replicates using reverse transcription of RNA into DNA. (i-sis.org.uk)
  • When CaMV genes are inserted into the DNA of the plant chromosome those genes may recombine with infecting CaMV virus. (i-sis.org.uk)
  • Wintermantel and Schoelz (1996) found that recombination was observable in every plant when virus invaded transgenic plants with CaMV genes inserted on plant chromosome. (i-sis.org.uk)
  • They believed that most observed recombination occurred in the cytoplasm during reverse transcription and that there was little chance for recombination between invading virus and CaMV transgenes on the chromosome. (i-sis.org.uk)
  • Here, we show that cauliflower mosaic virus ( CaMV ) MP contains three tyrosine-based sorting signals that interact with an Arabidopsis ( Arabidopsis thaliana ) μA-adaptin subunit. (plantphysiol.org)
  • Altogether, these results demonstrate that CaMV MP traffics in the endocytic pathway and that virus viability depends on functional host endomembranes. (plantphysiol.org)
  • Here, we focus on this second group of tubule-forming MP s and examine the intracellular trafficking of cauliflower mosaic virus ( CaMV ) MP . (plantphysiol.org)
  • Translation of the polycistronic 35S RNA of CaMV (cauliflower mosaic virus) occurs via a reinitiation mechanism, which requires TAV (transactivator/viroplasmin). (biochemsoctrans.org)
  • Until now, identification of the OAS in the tripartite Alfalfa mosaic virus (AlMV), a member of the Bromoviridae family, has been elusive. (mdpi.com)
  • The sequence similarities of RNA replication genes and strategies for BMV have been shown to extend to a wide range of plant and animal viruses beyond the alphaviruses, including many other positive-strand RNA viruses from other families. (wikipedia.org)
  • From replication testing, it is believed the 109S component is the panicum mosaic pathogen and the 42S component of the pathogen is the panicum satellite virus because the 109S component replicates independently while 42S cannot replicate without the presence of the 109S component. (wikipedia.org)
  • the amiRNA targets were fully conserved in all three isolates, indicating virus replication on some transgenics was not a result of mutational escape by the virus. (wiley.com)
  • Several lines of evidence suggest that multiple steps in positive-strand RNA virus RNA replication depend on specific host factors. (pnas.org)
  • The replication complex of each virus assembles on specific membrane sites in the infected cell ( 3 - 5 ), and such association with cell membranes appears particularly important for positive-strand RNA synthesis ( 6 ). (pnas.org)
  • The localization of MP with ER membranes is consistent with results of several studies indicating that ER membranes act as sites for virus replication and virus protein synthesis ( 6 , 42 , 76 ). (asm.org)
  • Here, we constructed various mutants by deleting sequences within the 3′ NTR of AlMV subgenomic (sg) RNA4 (same as of RNA3) and examined the effect of these deletions on replication and translation of chimeric Tobacco mosaic virus (TMV) expressing AlMV sgRNA4 from the TMV CP sg promoter (Av/A4) in tobacco protoplasts and Nicotiana benthamiana plants. (mdpi.com)
  • The satRNAs are dependent on CMV for their replication, encapsidation, and dispersion, but they are not necessary for the life cycle of the virus. (plantcell.org)
  • Members of Tombusviridae are transmitted as positive sense single-stranded non-enveloped RNA viruses, with an icosohedral capsid. (wikipedia.org)
  • The appearance of the interior surface of the virus capsid, along with buried surface area calculations, suggest that a pentameric unit is lost during decapsidation. (rcsb.org)
  • During virus assembly, the capsid interacts with genomic RNA to form nucleocapsids. (neuromics.com)
  • Despite the fact that CMV has only 19% capsid protein sequence identity (34% similarity) to cowpea chlorotic mottle virus (CCMV), the core structures of these two members of the Bromoviridae family are highly homologous. (asm.org)
  • To further investigate this virus, phylogenetic and population genetics based methods were used to investigate the temporal and spatial dynamics of the evolutionary mechanism and genetic variability among the DsMV isolates. (researchgateway.ac.nz)
  • Analysis of DsMV isolates on a temporal scale suggested the role of stochastic or selection-fitness levels are the key mechanisms in the dynamics of plant virus population genetics and evolution. (researchgateway.ac.nz)
  • Wheat streak mosaic virus (WSMV) is a persistent threat to wheat production, necessitating novel approaches for protection. (wiley.com)
  • The virus poses a new threat to the wheat production and required development of new bio-security practices. (wiley.com)
  • The widespread occurrence of the virus and its vector, the potential major impacts on yield, and the impracticality of managing the mites add to the priority of breeding virus-resistant varieties and developing alternative methods of virus control through development of virus-resistant transgenic wheat. (wiley.com)
  • There are other diseases of concern, but wheat streak mosaic is always found somewhere in this wheat growing region, and every couple of years, we have an epidemic of it,' Rush said. (southwestfarmpress.com)
  • In a separate study, Price planted an area of a wheat field in July and allowed it to become infested with the virus-carrying mites. (southwestfarmpress.com)
  • Identification of the amino acid residues and domains in the cysteine-rich protein of Chinese wheat mosaic virus that are important for RNA silencing suppression and subcellular localization. (biomedsearch.com)
  • Here, we present evidence that the conserved cysteine residues and Cys-Gly-X-X-His motif in the CRP of Chinese wheat mosaic virus (CWMV) are critical for protein stability and silencing suppression activity. (biomedsearch.com)
  • Wheat streak mosaic virus was confirmed on the white wheat variety Caledonia at a research plot in Williamston, Michigan last week. (msu.edu)
  • This virus is vectored by the wheat curl mite, Aceria tulipae . (msu.edu)
  • This could lead to plant death and a reduction of crop production which is why the study of mosaic viruses are essential to improve agriculture by both quantity and quality. (kenyon.edu)
  • Both viruses were equipped with fragments of the magnesium chelatase subunit H and phytoene desaturase genes. (cuvillier.de)
  • A remarkable similarity was demonstrated between the structure of CMV and that of cowpea chlorotic mottle virus (CCMV), another member of the Bromoviridae . (asm.org)
  • Understanding how these viruses replicate and targeting key points in their life cycle can help advance antiviral treatments worldwide. (wikipedia.org)