What are the segmented viruses?
Among viruses that infect vertebrates, those that carry segmented genomes belong to the Arenaviridae, Birnaviridae, Bunyavirales, Orthomyxoviridae, Picobirnaviridae, and Reoviridae. Reassortment has been documented to occur in nature for each of these viral taxa [1–6].
What is the advantage of segmented genome in viruses?
A segmented genome enables the virus to generate reassortants. In this process, the RNA molecules of different virus strains are mixed or reshuffled in doubly infected cells during replication and morphogenesis. In this way, progeny viruses can obtain new combinations of RNA segments and thus gain novel properties.
How do segmented viruses replicate?
Viruses with segmented genomes replicate in the nucleus, and the RdRp produces one monocistronic mRNA strand from each genome segment.
Are all viruses segmented?
Both DNA and RNA viruses can either single stranded or double stranded, with a circular, linear or segmented arrangement. DNA and RNA viruses are distinguished by their features, such as monopartite or multipartite. In monopartite, their genome is having a single nucleic acid molecule.
What does it mean when a virus is said to have a segmented genome?
A viral genome fragmented into two or more nucleic acid molecules. For example, the alfalfa mosaic virus has four different RNA segments, each packaged in a different virion.
How do you remember the difference between DNA and RNA?
RNA stands for “ribonucleic acid,” which is a simple way to remember that it contains the sugar ribose. DNA, on the other hand, stands for “deoxyribonucleic acid.” Its sugar is deoxyribose, which is identical to ribose except it is missing a hydroxyl (-OH) group on its second carbon.
How is a virus sequence compared with other virus sequences?
For example, after CDC sequences an influenza A (H3N2) virus collected through surveillance, the virus sequence is cataloged with other virus sequences that have a similar HA gene (H3), and a similar NA gene (N2). As part of this process, CDC compares the new virus sequence with the other virus sequences, and looks for differences among them.
How many gene segments are in the influenza virus?
Influenza A and B viruses – the primary influenza viruses that infect people – are RNA viruses that have eight gene segments.
What is the significance of concatemers in viral replication?
This insures an orderly production of viral proteins. The replication of several dsDNA viruses results in the production of concatemers, where several viral genomes are linked together due to short single-stranded regions with terminal repeats.
How is the A(H3N2) virus phylogenetic tree determined?
As part of this process, CDC compares the new virus sequence with the other virus sequences, and looks for differences among them. CDC then uses a phylogenetic tree to visually represent how genetically different the A (H3N2) viruses are from each other. CDC performs genetic characterization of influenza viruses year round.