''Crinivirus'', formerly the ''lettuce infectious yellows virus 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 ...

''. They are linear, single-stranded positive sense

RNA virus An RNA virus is a virusother than a retrovirusthat has ribonucleic acid (RNA) as its genetic material. The nucleic acid is usually single-stranded RNA ( ssRNA) but it may be double-stranded (dsRNA). Notable human diseases caused by RNA viruse ...

es (and are therefore

group IV The carbon group is a periodic table group consisting of carbon (C), silicon (Si), germanium (Ge), tin (Sn), lead (Pb), and flerovium (Fl). It lies within the p-block. In modern IUPAC notation, it is called group 14. In the field of semicond ...

). There are 14 species in this genus. Diseases associated with this genus include: yellowing and necrosis, particularly affecting the phloem. Examples of species whose entire

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 ...

s have been

sequenced In genetics and biochemistry, sequencing means to determine the primary structure (sometimes incorrectly called the primary sequence) of an unbranched biopolymer. Sequencing results in a symbolic linear depiction known as a sequence which succi ...

that are currently classified into the genus include the Sweet potato chlorotic stunt virus (SPCSV) and the Lettuce infectious yellows virus (LIYV).ICTVdB Management (2006)

Genetics

The viruses of this genus have segmented, bipartite genomes that add up to 7,500–19,500

nucleotide Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecul ...

s in length. Their genomes also code for

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respon ...

s that do not form part of the virion particles as well as structural proteins. The Universal Virus Database describes that their genome sequences near their 3'-ends are capable of hairpin-loop formation and also believe that their 5'-ends may have methylated caps. Each of the viral RNA molecules contains 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 ...

. The pseudoknot is unusual in that it contains a small

stem-loop Stem-loop intramolecular base pairing is a pattern that can occur in single-stranded RNA. The structure is also known as a hairpin or hairpin loop. It occurs when two regions of the same strand, usually complementary in nucleotide sequence wh ...

structure inside loop L1. In the related genus

Closterovirus ''Closterovirus'', also known as beet yellows viral group, is a genus of viruses, in the family ''Closteroviridae ''Closteroviridae'' is a family of viruses. Plants serve as natural hosts. There are four genera and 59 species in this famil ...

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

Structure

Viruses in the genus ''Crinivirus'' are non-enveloped, with bipartite filamentous geometries. The diameter is around 10-13 nm, with a length of 700-900 nm. Genomes are linear and bipartite, around 17.6kb in length.

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. The virus is transmitted via a vector (bemisia tabaci). Transmission route is mechanical.

Taxonomy

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

Abutilon yellows virus ''Abutilon yellows virus'' (AbYV (sometimes AYB) is a virus of the genus ''Crinivirus ''Crinivirus'', formerly the ''lettuce infectious yellows virus group'', is a genus of viruses, in the family ''Closteroviridae''. They are linear, single ...

'' *'' Bean yellow disorder virus'' *'' Beet pseudoyellows virus'' *'' Blackberry yellow vein-associated virus'' *''

Cucurbit yellow stunting disorder virus Cucurbit may refer to:- *A plant of the family Cucurbitaceae *The lower part of an alembic *Cucurbit flute The ''hulusi'' (traditional: 葫蘆絲; simplified: 葫芦丝; pinyin: húlúsī), also known as the cucurbit flute and the gourd ...

'' *'' Diodia vein chlorosis virus'' *'' Lettuce chlorosis virus'' *''

Lettuce infectious yellows virus Lettuce infectious yellows virus (LIYV) 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 ...

'' *''

Potato yellow vein virus The Potato yellow vein virus (PYVV) is a plant pathogen of the ''Closteroviridae'' family. It is a whitefly-transmitted closterovirus vectored by ''Trialeurodes vaporariorum'', which is known to cause a yellowing disease in potato crops in South ...

'' *'' Strawberry pallidosis-associated virus'' *''

Sweet potato chlorotic stunt virus Sweetness is a basic taste most commonly perceived when eating foods rich in sugars. Sweet tastes are generally regarded as pleasurable. In addition to sugars like sucrose, many other chemical compounds are sweet, including aldehydes, ket ...

'' *''

Tetterwort vein chlorosis virus Tetterwort is a common name for several plants in the family Papaveraceae and may refer to: *'' Chelidonium majus'', native to Europe *''Sanguinaria canadensis ''Sanguinaria canadensis'', bloodroot, is a perennial, herbaceous flowering plant ...

'' *''

Tomato chlorosis virus The tomato is the edible berry of the plant ''Solanum lycopersicum'', commonly known as the tomato plant. The species originated in western South America, Mexico, and Central America. The Mexican Nahuatl word gave rise to the Spanish word , ...

'' *''

Tomato infectious chlorosis virus The tomato is the edible berry of the plant ''Solanum lycopersicum'', commonly known as the tomato plant. The species originated in western South America, Mexico, and Central America. The Mexican Nahuatl word gave rise to the Spanish word , ...

References

External links

ICTV Report: ''Closteroviridae''

Rfam entry for 3'-terminal pseudoknot in SPCSV

Rfam entry for 3'-terminal pseudoknot of CuYV/BPYV

Rfam entry for 3'-terminal pseudoknot in PYVV
{{Taxonbar, from=Q3002668 Closteroviridae Viral plant pathogens and diseases Virus genera