''Tymoviridae'' is a family of single-stranded positive sense

RNA Ribonucleic acid (RNA) is a polymeric molecule essential in various biological roles in coding, decoding, regulation and expression of genes. RNA and deoxyribonucleic acid ( DNA) are nucleic acids. Along with lipids, proteins, and carbohydra ...

viruses 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 1 ...

in the order ''

Tymovirales ''Tymovirales'' is an order of viruses with five families. The group consists of viruses which have positive-sense, single-stranded RNA genomes. Their genetic material is protected by a special coat protein. Description Tymoviruses are mainly ...

''. Plants serve as natural hosts. There are 42 species in this family, assigned to three genera, with two species unassigned to a genus.

Taxonomy

The family includes the following three genera: * ''

Maculavirus ''Maculavirus'' is a genus of viruses in the order ''Tymovirales'', in the family ''Tymoviridae ''Tymoviridae'' is a family of single-stranded positive sense RNA viruses in the order '' Tymovirales''. Plants serve as natural hosts. There a ...

'' * ''

Marafivirus ''Marafivirus'' is a genus of viruses in the order ''Tymovirales'', in the family ''Tymoviridae ''Tymoviridae'' is a family of single-stranded positive sense RNA viruses in the order '' Tymovirales''. Plants serve as natural hosts. There a ...

'' * ''

Tymovirus ''Tymovirus'' is a genus of viruses in the order ''Tymovirales'', in the family ''Tymoviridae''. Plants serve as natural hosts. There are 28 species in this genus. Taxonomy The genus contains the following species: * ''Anagyris vein yellowing ...

'' Additionally, the following two species are not assigned to a genus: * ''

Bombyx mori latent virus ''Bombyx'' is the genus of true silk moths or mulberry silk moths of the family Bombycidae, also known as silkworms, which are the larvae or caterpillars of silk moths. The genus was erected as a subgenus by Carl Linnaeus in his 10th edition of ...

'' * ''

Poinsettia mosaic virus ''Poinsettia mosaic virus'' (PnMV) is a pathogenic plant virus Plant viruses are viruses that affect plants. Like all other viruses, plant viruses are obligate intracellular parasites that do not have the molecular machinery to replicate wi ...

Proposed viruses

Culex tymovirus ''Culex'' is a genus of mosquitoes, several species of which serve as vectors of one or more important diseases of birds, humans, and other animals. The diseases they vector include arbovirus infections such as West Nile virus, Japanese encep ...

Wang L, Lv X, Zhai Y, Fu S, Wang D, Rayner S, Tang Q, Liang G (2012) Genomic characterization of a novel virus of the family tymoviridae isolated from mosquitoes. PLoS One 7(7):e39845. * Fig fleck-associated virus

Virology

The virions are non-enveloped and isometric with a diameter of around 30 nm, with an

icosahedral In geometry, an icosahedron ( or ) is a polyhedron with 20 faces. The name comes and . The plural can be either "icosahedra" () or "icosahedrons". There are infinitely many non- similar shapes of icosahedra, some of them being more symmetrica ...

structure and a

triangulation number A capsid is the protein shell of a virus, enclosing its genetic material. It consists of several oligomeric (repeating) structural subunits made of protein called protomers. The observable 3-dimensional morphological subunits, which may or may ...

T=3. The linear

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 ge ...

is between of 6–7.5 kilobases in length and encodes one large

open reading frame In molecular biology, open reading frames (ORFs) are defined as spans of DNA sequence between the start and stop codons. Usually, this is considered within a studied region of a prokaryotic DNA sequence, where only one of the six possible readin ...

. It is capped at the 5’ terminus. The 3’ terminus may have a

tRNA Transfer RNA (abbreviated tRNA and formerly referred to as sRNA, for soluble RNA) is an adaptor molecule composed of RNA, typically 76 to 90 nucleotides in length (in eukaryotes), that serves as the physical link between the mRNA and the amino ac ...

-like structure or a polyA tract, depending upon the species. The genome is relatively

cytosine Cytosine () ( symbol C or Cyt) is one of the four nucleobases found in DNA and RNA, along with adenine, guanine, and thymine (uracil in RNA). It is a pyrimidine derivative, with a heterocyclic aromatic ring and two substituents attached (an am ...

rich.

Life cycle

Viral replication is cytoplasmic, and is lysogenic. Entry into the host cell is achieved by penetration into the host cell. Replication follows the positive stranded RNA virus replication model. Positive stranded RNA virus transcription is the method of transcription. Translation takes place by leaky scanning. The virus exits the host cell by monopartite non-tubule guided viral movement. Plants serve as the natural host. The virus is transmitted via a vector (insects). Transmission routes are vector and mechanical.

References

External links

ICTV

UniProt Taxonomy
{{Taxonbar, from=Q6729 Virus families

Taxonomy

Proposed viruses

Virology

Life cycle

References

Further reading

External links