|
Ngari Virus
Ngari virus (NRIV) is a single-stranded, negative sense, tri-segmented RNA virus. It is a subtype of the Bunyamwera virus (BUNV) and closely related to the Batai virus (BATV). NRIV is the only reassortment virus of the subtypes. There is evidence suggesting that NRIV stems from a naturally occurring reassortment event in which a host was infected with both BUNV and BATV. It is commonly found in areas that experience an outbreak of Rift Valley fever virus In geology, a rift is a linear zone where the lithosphere is being pulled apart and is an example of extensional tectonics. Typical rift features are a central linear downfaulted depression, called a graben, or more commonly a half-graben wi ... (RFVF) Transmission The primary form of transmission of the virus to humans is through mosquitos. Although mosquitos are the primary source, the virus was also detected in Ixodid ticks found on cattle in Guinea but there is no evidence indicating that they are able to spread th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coding Strand
When referring to DNA transcription, the coding strand (or informational strand) is the DNA strand whose base sequence is identical to the base sequence of the RNA transcript produced (although with thymine replaced by uracil). It is this strand which contains codons, while the non-coding strand contains anticodons. During transcription, RNA Pol II binds to the non-coding template strand, reads the anti-codons, and transcribes their sequence to synthesize an RNA transcript with complementary bases. By convention, the coding strand is the strand used when displaying a DNA sequence. It is presented in the 5' to 3' direction. Wherever a gene exists on a DNA molecule, one strand is the coding strand (or sense strand), and the other is the noncoding strand (also called the antisense strand, anticoding strand, template strand or transcribed strand). Strands in transcription bubble During transcription, RNA polymerase unwinds a short section of the DNA double helix near the start o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Negative-strand RNA Virus
Negative-strand RNA viruses (−ssRNA viruses) are a group of related viruses that have negative-sense, single-stranded genomes made of ribonucleic acid. They have genomes that act as complementary strands from which messenger RNA (mRNA) is synthesized by the viral enzyme RNA-dependent RNA polymerase (RdRp). During replication of the viral genome, RdRp synthesizes a positive-sense antigenome that it uses as a template to create genomic negative-sense RNA. Negative-strand RNA viruses also share a number of other characteristics: most contain a viral envelope that surrounds the capsid, which encases the viral genome, −ssRNA virus genomes are usually linear, and it is common for their genome to be segmented. Negative-strand RNA viruses constitute the phylum ''Negarnaviricota'', in the kingdom '' Orthornavirae'' and realm '' Riboviria''. They are descended from a common ancestor that was a double-stranded RNA (dsRNA) virus, and they are considered to be a sister clade of reovi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bunyamwera Orthobunyavirus
''Bunyamwera orthobunyavirus'' (BUNV) is a negative-sense, single-stranded enveloped RNA virus. It is assigned to the ''Orthobunyavirus'' genus, in the ''Bunyavirales'' order. ''Bunyamwera orthobunyavirus'' can infect both humans and ''Aedes aegypti'' (yellow fever mosquito). It is named for Bunyamwera, a town in western Uganda, where it was isolated in 1943. Reassortant viruses derived from ''Bunyamwera orthobunyavirus'', such as '' Ngari virus'', have been associated with large outbreaks of viral haemorrhagic fever in Kenya and Somalia. Molecular biology The genetic structure of ''Bunyamwera orthobunyavirus'' is typical for ''Bunyavirales'' viruses, which are an order of enveloped negative-sense, single-stranded RNA viruses with a genome split into three parts—Small (S), Middle (M), and Large (L). The L RNA segment encodes an RNA-dependent RNA polymerase (L protein), the M RNA segment encodes two surface glycoproteins (Gc and Gn) and a nonstructural protein (NSm), whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Batai Orthobunyavirus
''Batai orthobunyavirus'' (BATV) is a RNA virus belonging to order ''Bunyavirales'', genus ''Orthobunyavirus''. Introduction Batai virus (BATV) is an enveloped, single-stranded, negative sense RNA genome. It is a member of the genus Orthobunyavirus and belongs to the order Bunyavirales; it was first isolated from Culex mosquitoes in Malaysia in 1955. Evidence from serological surveillance and virus isolation shows that this virus is widely distributed around the world. Similar to other orthobunyaviruses it contributes to both human and animal disease. In humans it has been noted in causing severe fever, and in bovines has been associated with premature birth, birth defects, and increased abortion rates. It is transmitted through mosquito bites, ticks, and biting midges, and occurs from cold to tropical regions of Africa, Asia, and Europe. Structure The structure of Batai virus (BATV) consists of an enveloped nucleocapsid that is composed of three RNA segments: small (S), medium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reassortment
Reassortment is the mixing of the genetic material of a species into new combinations in different individuals. Several different processes contribute to reassortment, including assortment of chromosomes, and chromosomal crossover. It is particularly used when two similar viruses that are infecting the same cell exchange genetic material. In particular, reassortment occurs among influenza viruses, whose genomes consist of eight distinct segments of RNA. These segments act like mini-chromosomes, and each time a flu virus is assembled, it requires one copy of each segment. If a single host (a human, a chicken, or other animal) is infected by two different strains of the influenza virus, then it is possible that new assembled viral particles will be created from segments whose origin is mixed, some coming from one strain and some coming from another. The new reassortant strain will share properties of both of its parental lineages. Reassortment is responsible for some of the major ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
