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Chrymotiviricetes
''Ghabrivirales'' is an order of double-stranded RNA viruses. It is the only order in the class ''Chrysmotiviricetes''. The name of the class is a portmanteau of member families: ''chrys''oviridae, ''m''egabirnaviridae, and ''toti''viridae; and -''viricetes'' which is the suffix for a virus class. The name of the order derives from Said ''Ghabri''al, a pioneering researcher who studied viruses in this order, and -''virales'' which is the suffix for a virus order. Taxonomy The following families are recognized: *'' Chrysoviridae'' *'' Megabirnaviridae'' *'' Quadriviridae'' *''Totiviridae ''Totiviridae'' is a family of double-stranded RNA viruses. Giardia lamblia, leishmania, trichomonas vaginalis, and fungi serve as natural hosts. The name of the group derives from Latin ''toti'' which means undivided or whole. There are 28 spec ...'' References Viruses {{Virus-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Double-stranded RNA Viruses
Double-stranded RNA viruses (dsRNA viruses) are a polyphyletic group of viruses that have double-stranded genomes made of ribonucleic acid. The double-stranded genome is used to transcribe a positive-strand RNA by the viral RNA-dependent RNA polymerase (RdRp). The positive-strand RNA may be used as messenger RNA (mRNA) which can be translated into viral proteins by the host cell's ribosomes. The positive-strand RNA can also be replicated by the RdRp to create a new double-stranded viral genome. Double-stranded RNA viruses are classified in two separate phyla ''Duplornaviricota'' and ''Pisuviricota'' (specifically class ''Duplopiviricetes''), which are in the kingdom ''Orthornavirae'' and realm ''Riboviria''. The two groups do not share a common dsRNA virus ancestor. Double-stranded RNA viruses evolved two separate times from positive-strand RNA viruses. In the Baltimore classification system, dsRNA viruses belong to Group III. Virus group members vary widely in host range (anim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saccharomyces Cerevisiae Virus L-A
''Saccharomyces cerevisiae virus L-A'', also called L-A helper virus, is a member of the ''Totiviridae'' family of viruses found primarily in ''Saccharomyces cerevisiae''. Its discovery in the 1970s was the main starting point of research on yeast virology. It is a ~4.6 kb double-stranded RNA virus with no extracellular phase and so is inherited through vertical cytoplasmic transmission. Additionally, in many strains of the yeast, it is found along with another virus called the M virus (or "M dsRNA", "Saccharomyces cerevisiae killer virus"), known to encode the killer toxin in many ''S. cerevisiae'' strains which confers the ability to kill neighboring sensitive cells that do not harbor the virus. It is indeed for this reason the virus is referred to as a helper virus, due to the M genome's dependence on it for its own survival and replication. (More recently, the M dsRNA is described as a satellite RNA.) A Yeast lineage with a M/killer virus is known as a " killer strain". The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portmanteau
A portmanteau word, or portmanteau (, ) is a blend of wordsGarner's Modern American Usage , p. 644. in which parts of multiple words are combined into a new word, as in ''smog'', coined by blending ''smoke'' and ''fog'', or ''motel'', from ''motor'' and ''hotel''. In , a portmanteau is a single morph that is analyzed as representing two (or more) underlying s. When portmanteaus shorten es ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virus
A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898,Dimmock p. 4 more than 9,000 virus species have been described in detail of the millions of types of viruses in the environment. Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity. The study of viruses is known as virology, a subspeciality of microbiology. When infected, a host cell is often forced to rapidly produce thousands of copies of the original virus. When not inside an infected cell or in the process of infecting a cell, viruses exist in the form of independent particles, or ''virions'', consisting of (i) the genetic material, i. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chrysoviridae
''Chrysoviridae'' is a family of double-stranded RNA viruses. Members of the family are called chrysoviruses. Virology The capsid is about 35-40 nm in diameter. The genome In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding g ... has four segments (tetrapartit). These segments are separately encapsulated.SIBChrysoviridae at: Expasy ViralZone Taxonomy The following genera are recognized: * '' Alphachrysovirus'' * '' Betachrysovirus'' References External links ICTV Report: ''Chrysoviridae'' Virus families Riboviria {{virus-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megabirnaviridae
''Megabirnaviridae'' is a family of double-stranded RNA viruses with one genus ''Megabirnavirus'' which infects fungi. The group name derives from member's ''bi''partite ds''RNA'' genome and ''mega'' that is greater genome size (16 kbp) than families ''Birnaviridae'' (6 kbp) and '' Picobirnaviridae'' (4 kbp). There is only one species in this family: ''Rosellinia necatrix megabirnavirus 1''. Diseases associated with this family include: reduced host virulence. Structure Viruses in the family ''Megabirnaviridae'' are non-enveloped, with icosahedral geometries, and T=1 symmetry. The diameter is around 50 nm. Genome The genome is composed of two double-stranded RNA segments of 7.2–8.9 kbp each and of a total length of 16.1 kbp. The genome codes for four proteins. Life cycle Viral replication is cytoplasmic. Entry into the host cell is achieved by penetration into the host cell. Replication follows the double-stranded RNA virus replication model. Double-stranded RNA vir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadriviridae
''Quadriviridae'' is a family of double-stranded RNA viruses with a single genus ''Quadrivirus''. The fungi ''Rosellinia necatrix'' serves as a natural host. The name of the group derives from the ''quadri''partite genome of its members where in Latin ''quad'' means four. There is only one species in this family: ''Rosellinia necatrix quadrivirus 1''. Structure Mycoviruses in the family ''Quadriviridae'' have a non-enveloped isometric capsid which consists of 60 copies of heterodimers of the structural proteins P2 and P4. The diameter of the capsid is around 48 nm. Genome Family member genomes are composed of double-stranded RNA. They are divided in to four segments which each code for a protein. The length of the different segments are between 3.5 to 5.0 kbp. The total genome is around 16.8 kbp. Inside the capsid with the genome there is also the RNA-dependent RNA polymerase. Life cycle Quadriviruses are transmitted internally. They are propagated during cell divis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Totiviridae
''Totiviridae'' is a family of double-stranded RNA viruses. Giardia lamblia, leishmania, trichomonas vaginalis, and fungi serve as natural hosts. The name of the group derives from Latin ''toti'' which means undivided or whole. There are 28 species in this family, assigned to 5 genera. Structure Viruses in the family ''Totiviridae'' are non-enveloped, double-stranded RNA viruses with icosahedral geometries, and T=2 symmetry. The virion consists of a single capsid protein and is about 40 nanometers in diameter. Genome The genome is composed of a monopartite, linear double-stranded RNA molecule of 4.6–6.7 kilobases. It contains two overlapping open reading frames (ORF) – ''gag'' and ''pol –'' which respectively encode the capsid protein and the RNA-dependent RNA polymerase. Some totiviruses contain a third small potential ORF. Life cycle Viral replication is cytoplasmic. Replication follows the double-stranded RNA virus replication model. Double-stranded RNA virus tran ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
