''Closterovirus'', also known as beet yellows viral group, is a genus of

viruses A virus is a submicroscopic infectious agent that replicates only inside the living cells Cell most often refers to: * Cell (biology), the functional basic unit of life Cell may also refer to: Locations * Monastic cell, a small room ...

, in the family ''

Closteroviridae ''Closteroviridae'' is a family of viruses. Plants serve as natural hosts. There are four genera and 59 species in this family, seven of which are unassigned to a genus. Diseases associated with this family include: yellowing and necrosis, parti ...

''. Plants serve as natural hosts. There are 17 species in this genus. Diseases associated with this genus include: yellowing and necrosis, particularly affecting the phloem. This genus has a probably worldwide distribution and includes among other viral species the '' Beet yellows virus'' (the type species) and ''

Citrus tristeza virus Citrus tristeza virus (CTV) is a viral species of the genus ''Closterovirus'' that causes the most economically damaging disease to its namesake plant genus, ''Citrus''. The disease has led to the death of millions of ''Citrus'' trees all ove ...

'', rather economically important plant diseases. At least some species require vectors such as

aphid Aphids are small sap-sucking insects and members of the superfamily Aphidoidea. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white woolly aphids. A ...

s or

mealybug Mealybugs are insects in the family Pseudococcidae, unarmored scale insects found in moist, warm habitats. Many species are considered pests as they feed on plant juices of greenhouse plants, house plants and subtropical trees and also act as a ...

s for their transmission from plant to plant.

Taxonomy

The following species are assigned to the genus: * ''

Arracacha virus 1 Arracacha (''Arracacia xanthorrhiza'') is a root vegetable that originates in the Andes, whose starchy taproot is a popular food item across South America where it is a major commercial crop. Common names Being a South American plant, its most ...

'' * '' Beet yellow stunt virus'' * '' Beet yellows virus'' * '' Blackcurrant closterovirus 1'' * '' Burdock yellows virus'' * ''

Carnation necrotic fleck virus Carnation necrotic fleck virus (CNFV) is a plant pathogenic virus of the family ''Closteroviridae ''Closteroviridae'' is a family of viruses. Plants serve as natural hosts. There are four genera and 59 species in this family, seven of which a ...

'' * ''

Carrot closterovirus 1 The carrot (''Daucus carota'' subsp. ''sativus'') is a root vegetable, typically orange in color, though purple, black, red, white, and yellow cultivars exist, all of which are domesticated forms of the Daucus carota, wild carrot, ''Daucus ...

'' * ''

Carrot yellow leaf virus Summary Host The carrot yellow-leaf virus (CYLV) infects carrots, particularly the carrot root cells. There are viruses that are similar to CYLV which affect hogweed and beet roots as well.Adams, I. P., Skelton, A., Macarthur, R., Hodges, T., Hi ...

'' * ''

Grapevine leafroll-associated virus 2 Grapevine leafroll-associated virus 2 (GRLaV2) is a virus infecting grapevine in the genus '' Closterovirus''. It is associated with rugose wood condition of grapevine.According to Bosciai, 1995, ''grapevine corky bark-associated virus'' (GCBaV) i ...

'' * ''

Mint virus 1 MiNT is Now TOS (MiNT) is a free software alternative operating system kernel for the Atari ST system and its successors. It is a multi-tasking alternative to TOS and MagiC. Together with the free system components fVDI device drivers, XaAES ...

'' * ''

Raspberry leaf mottle virus The raspberry is the edible fruit of a multitude of plant species in the genus '' Rubus'' of the rose family, most of which are in the subgenus '' Idaeobatus''. The name also applies to these plants themselves. Raspberries are perennial wi ...

'' * ''

Rehmannia virus 1 ''Rehmannia'' is a genus of seven species of flowering plants in the order Lamiales and family Orobanchaceae, endemic to China. It has been placed as the only member of the monotypic tribe Rehmannieae, but molecular phylogenetic studies suggest ...

'' * ''

Rose leaf rosette-associated virus ''Rose leaf rosette-associated virus'' is a +ssRNA closterovirus which causes a unique, unusually dense and small rosette leaf habit on ''Rosa multiflora ''Rosa multiflora'' — ( syn. ''Rosa polyantha'') is a species of rose known commonl ...

'' * ''

Strawberry chlorotic fleck-associated virus The garden strawberry (or simply strawberry; ''Fragaria × ananassa'') is a widely grown hybrid species of the genus ''Fragaria'', collectively known as the strawberries, which are cultivated worldwide for their fruit. The fruit is widely app ...

'' * ''

Tobacco virus 1 Tobacco is the common name of several plants in the genus ''Nicotiana'' of the Family (biology), family Solanaceae, and the general term for any product prepared from the curing of tobacco, cured leaves of these plants. Nicotiana#Species, M ...

'' * ''

Wheat yellow leaf virus Wheat yellow leaf virus (WYLV) is a wheat (''Triticum'' spp. L.), barley (''Hordeum vulgare'' L.), rye (''Secale cereale'' M.Bieb.), and oat (''Avena sativa'' L.) pathogenic virus of the family ''Closteroviridae''. WYLV virions are 1600–1850 ...

RNA pseudoknot

The viral RNA molecules of some members of this genus contain four hair-pin structures and a

pseudoknot __NOTOC__ A pseudoknot is a nucleic acid secondary structure containing at least two stem-loop structures in which half of one stem is intercalated between the two halves of another stem. The pseudoknot was first recognized in the turnip yellow ...

in the

3'UTR In molecular genetics, the three prime untranslated region (3′-UTR) is the section of messenger RNA (mRNA) that immediately follows the translation termination codon. The 3′-UTR often contains regulatory regions that post-transcriptionally ...

. These secondary structures have been found to be important in viral RNA replication.

Life cycle

Viral replication is cytoplasmic. 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. The virus exits the host cell by tubule-guided viral movement. Plants serve as the natural host. Transmission routes are mechanical.

Structure

Viruses in ''Closterovirus'' are non-enveloped, with flexuous and filamentous geometries. The diameter is around 10-13 nm, with a length of 1250-2200 nm. Genomes are linear, around 19.3kb in length.

References

External links

ICTV Report: ''Closteroviridea''

* {{Taxonbar, from=Q5135471 Closteroviridae Viral plant pathogens and diseases Virus genera