|
Totiviridae
''Totivirus'' is a genus of double-stranded RNA viruses in the family ''Orthototiviridae''. Fungi serve as natural hosts. The name of the group derives from Latin ''toti'' which means undivided or whole. There are 32 species in this genus. Structure Viruses in the genus ''Totivirus'' are non-enveloped, with icosahedron, icosahedral symmetry, and T=2 architecture. The diameter is around 40 nm. Genome Totiviruses have a genome of 4700–6700 nucleotides in length and only a single copy of the genome is present in the particle. The nucleic acid content of a totivirus capsid is usually of one segment but can also contain three or four segments of linear dsRNA, double stranded RNA. The genome contains two large overlapping open reading frames (ORFs). These open reading frames (ORFs) code for a capsid protein (CP) and an RNA-dependent RNA polymerase (RdRp). The 5' end of the positive strand of the dsRNA genome has no cap and is very structured. Totiviruses contain a long 5' unt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
L-A Helper Virus
''Saccharomyces cerevisiae virus L-A'', also called L-A helper virus, is a member of the ''Totivirus'' genus 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". Ther ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Totivirus Go
''Totivirus'' is a genus of double-stranded RNA viruses in the family '' Orthototiviridae''. Fungi serve as natural hosts. The name of the group derives from Latin ''toti'' which means undivided or whole. There are 32 species in this genus. Structure Viruses in the genus ''Totivirus'' are non-enveloped, with icosahedral symmetry, and T=2 architecture. The diameter is around 40 nm. Genome Totiviruses have a genome of 4700–6700 nucleotides in length and only a single copy of the genome is present in the particle. The nucleic acid content of a totivirus capsid is usually of one segment but can also contain three or four segments of linear double stranded RNA. The genome contains two large overlapping open reading frames (ORFs). These open reading frames (ORFs) code for a capsid protein (CP) and an RNA-dependent RNA polymerase (RdRp). The 5' end of the positive strand of the dsRNA genome has no cap and is very structured. Totiviruses contain a long 5' untranslated region ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
