| Nanoviridae | |
|---|---|
 | |
| Faba bean necrotic yellows virus (FBNYV), genus Nanovirus | |
Virus classification  | |
| (unranked): | Virus |
| Realm: | Monodnaviria |
| Kingdom: | Shotokuvirae |
| Phylum: | Cressdnaviricota |
| Class: | Arfiviricetes |
| Order: | Mulpavirales |
| Family: | Nanoviridae |
| Genera | |
Nanoviridae is a family of viruses. [1] Plants serve as natural hosts. There are currently 12 species in this family, divided among 2 genera and one unassigned species. [2] Diseases associated with this family include: stunting. [2] [3] [4]
The recognized genera are:
The unassigned species is Coconut foliar decay virus . [2]
Viruses in the family Nanoviridae are non-enveloped, with icosahedral and round geometries, and T=1 symmetry. The diameter is around 18–19 nm. [2] [3]
| Genus | Structure | Symmetry | Capsid | Genomic arrangement | Genomic segmentation |
|---|---|---|---|---|---|
| Nanovirus | Icosahedral | T=1 | Non-enveloped | Circular | Segmented |
| Babuvirus | Icosahedral | T=1 | Non-enveloped | Circular | Segmented |
Viral replication is nuclear. Entry into the host cell is achieved by penetration into the host cell. Replication follows the ssDNA rolling circle model. [3] After infection of a host cell, the small DNA molecules that have become encapsidated with the genomic ssDNA act as primers. They bind to complementary regions and help in initiation of DNA synthesis by host polymerases. On completion of synthesis, there will be a double stranded intermediate that is transcribed unidirectionally. Most individual nanovirus particles only encode for a single protein. DNA-templated transcription is the method of transcription. The virus exits the host cell by nuclear pore export, and tubule-guided viral movement. Plants serve as the natural host. The virus is transmitted via a vector (aphids). [2] [3]
| Genus | Host details | Tissue tropism | Entry details | Release details | Replication site | Assembly site | Transmission |
|---|---|---|---|---|---|---|---|
| Nanovirus | Plants: legumes | Phloem | Viral movement; mechanical inoculation | Secretion; viral movement | Nucleus | Nucleus | Aphids |
| Babuvirus | Plants: musa species | Phloem | Viral movement; mechanical inoculation | Secretion; viral movement | Nucleus | Nucleus | Aphids |
Geminiviridae is a family of plant viruses that encode their genetic information on a circular genome of single-stranded (ss) DNA. There are 520 species in this family, assigned to 14 genera. Diseases associated with this family include: bright yellow mosaic, yellow mosaic, yellow mottle, leaf curling, stunting, streaks, reduced yields. They have single-stranded circular DNA genomes encoding genes that diverge in both directions from a virion strand origin of replication. According to the Baltimore classification they are considered class II viruses. It is the largest known family of single stranded DNA viruses.
Circoviridae is a family of DNA viruses. Birds and mammals serve as natural hosts. There are 101 species in this family, assigned to 2 genera. Diseases associated with this family include: PCV-2: postweaning multisystemic wasting syndrome; CAV: chicken infectious anemia.
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, particularly affecting the phloem.
Potyviridae is a family of positive-strand RNA viruses that encompasses more than 30% of known plant viruses, many of which are of great agricultural significance. The family has 12 genera and 235 species, three of which are unassigned to a genus.
Tombusviridae is a family of single-stranded positive sense RNA plant viruses. There are three subfamilies, 17 genera, and 95 species in this family. The name is derived from Tomato bushy stunt virus (TBSV).
Alphaherpesvirinae is a subfamily of viruses in the family Herpesviridae, primarily distinguished by reproducing more quickly than other subfamilies in the Herpesviridae. In animal virology the most important herpesviruses belong to the Alphaherpesvirinae. Pseudorabies virus is the causative agent of Aujeszky's disease in pigs and Bovine herpesvirus 1 is the causative agent of bovine infectious rhinotracheitis and pustular vulvovaginitis. Mammals serve as natural hosts. There are currently 45 species in this subfamily, divided among 5 genera with one species unassigned to a genus. Diseases associated with this subfamily include: HHV-1 and HHV-2: skin vesicles or mucosal ulcers, rarely encephalitis and meningitis, HHV-3: chickenpox (varicella) and shingles, GaHV-2: Marek's disease.
Baltimore classification is a system used to classify viruses based on their manner of messenger RNA (mRNA) synthesis. By organizing viruses based on their manner of mRNA production, it is possible to study viruses that behave similarly as a distinct group. Seven Baltimore groups are described that take into consideration whether the viral genome is made of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA), whether the genome is single- or double-stranded, and whether the sense of a single-stranded RNA genome is positive or negative.
Tectiviridae is a family of viruses with 10 species in five genera. Bacteria serve as natural hosts. Tectiviruses have no head-tail structure, but are capable of producing tail-like tubes of ~ 60×10 nm upon adsorption or after chloroform treatment. The name is derived from Latin tectus.
Partitiviridae is a family of double-stranded RNA viruses. Plants, fungi, and protozoa serve as natural hosts. It has been suggested that they can also infect bacteria. The name comes from the Latin partitius, which means divided, and refers to the segmented genome of partitiviruses. There are five genera and 60 species in the family, 15 of which are unassigned to a genus.
Endornaviridae is a family of viruses. Plants, fungi, and oomycetes serve as natural hosts. There are 31 species in this family, assigned to 2 genera. Members of Alphaendornavirus infect plants, fungi and the oomycete Phytophthora sp., members of Betaendornavirus infect ascomycete fungi.
Hypovirus is a genus of viruses, in the family Hypoviridae. Fungi serve as natural hosts. There are four species in this genus. Infection reduces the virulence of its parasitic host, making it a hyperparasite useful for blight control.
Alphaflexiviridae is a family of viruses in the order Tymovirales. Plants and fungi serve as natural hosts. There are 65 species in this family, assigned to six genera. Diseases associated with this family include: mosaic and ringspot symptoms.
Betaflexiviridae is a family of viruses in the order Tymovirales. Plants and fungi serve as natural hosts. There are 108 species in this family, assigned to 13 genera in two subfamilies. Diseases associated with this family include mosaic and ringspot symptoms.
Secoviridae is a family of viruses in the order Picornavirales. Plants serve as natural hosts. There are 8 genera and 86 species in this family, one of which is unassigned to a genus. The family was created in 2009 with the grouping of families Sequiviridae, now dissolved, and Comoviridae, now subfamily Comovirinae, along with the then unassigned genera Cheravirus, Sadwavirus, and Torradovirus.
Babuvirus is a genus of viruses, in the family Nanoviridae. Musa species serve as natural hosts. There are three species in this genus. Diseases associated with this genus include: stunting, severe necrosis and early plant death. BBTV induces banana bunchy top disease (BBTD).
Curtovirus is a genus of ssDNA viruses, in the family Geminiviridae. Dicotyledonous plants serve as natural hosts. Curtoviruses are transmitted by leafhoppers. There are three species in this genus. Diseases associated with this genus include: Curly top disease.
Nanovirus is a genus of viruses, in the family Nanoviridae. Legume plants serve as natural hosts. There are 11 species in this genus. Diseases associated with this genus include: stunting, severe necrosis and early plant death.
Becurtovirus is a genus of viruses, in the family Geminiviridae. Dicotyledonous plants serve as natural hosts. There are three species in this genus.
Eragrovirus is a genus of viruses, in the family Geminiviridae. Dicotyledonous plants serve as natural hosts. There is only one species in this genus: Eragrostis curvula streak virus.
Turncurtovirus is a genus of viruses, in the family Geminiviridae. Dicotyledonous plants serve as natural hosts. There are three species in this genus.