Leishmaniavirus | |
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Leishmaniavirus detected in Leishmania guyanensis parasites by immunofluorescence microscopy [1] Blue: DAPI-stained parasitic DNA Green: Leishmaniavirus dsRNA Red: Leishmaniavirus capsid | |
Virus classification | |
(unranked): | Virus |
Realm: | Riboviria |
Kingdom: | Orthornavirae |
Phylum: | Duplornaviricota |
Class: | Chrymotiviricetes |
Order: | Ghabrivirales |
Family: | Totiviridae |
Genus: | Leishmaniavirus |
Species [2] | |
LRV1 |
Leishmaniavirus (also known as Leishmania RNA virus or LRV) is a genus of double-stranded RNA virus, in the family Totiviridae . Protozoa serve as natural hosts, and Leishmaniaviruses are present in several species of the human protozoan parasite Leishmania . There are two species in this genus. [3] [4]
The presence of virus-like particles in Leishmania hertigi was first reported in 1974. [5] Various molecular descriptions of Leishmaniavirus were revealed over the subsequent decade, and mostly performed on members of the South American L. (Viannia) subgenus of parasites (which carries the LRV1 species) such as L. guyanensis (L.g) [6] [7] [8] [9] [10] [11] and then later in L. braziliensis (L.b). [1] [12] Recently, interest in these microbial viruses has been renewed by a finding that they may play a role in leishmanial pathology. [13]
The prevalence of LRV1 in human parasites is still largely unknown. So far, no LRV1 has been detected in other key L. (Viannia) species, such as L. panamensis (L.p). Further, LRV1 is rarely found in species outside the Neotropics, and so far, all Paleotropic LRV isolates have shown genetic differences that were sufficient to classify them in a new subcategory named “LRV2”. This variant of LRV was first classified in a single isolate of L. major (L.m), [14] and is recorded as the only and exceptional member of L.m to carry it. Recently, LRV2 has also been found in strains of L. aethiopica (L.ae) [15] isolated from biopsies of cutaneous leishmaniasis patients in the Ethiopian highlands.
The following species are assigned to the genus: [4]
Viruses in Leishmaniavirus are non-enveloped, with icosahedral geometries, and T=2 symmetry. The diameter is around 33 nm. Genomes are linear, around 5.3kb in length. The genome has 2 large open reading frames. [3]
Genus | Structure | Symmetry | Capsid | Genomic arrangement | Genomic segmentation |
---|---|---|---|---|---|
Leishmaniavirus | Icosahedral | T=2 | Non-enveloped | Linear | Monopartite |
Viral replication is cytoplasmic. Replication follows the double-stranded RNA virus replication model. Double-stranded RNA virus transcription is the method of transcription. Translation takes place by +1 ribosomal frameshifting. Protozoa serve as the natural host. [3]
Genus | Host details | Tissue tropism | Entry details | Release details | Replication site | Assembly site | Transmission |
---|---|---|---|---|---|---|---|
Leishmaniavirus | Protozoa: leishmania | None | Cell receptor endocytosis | Cell division | Cytoplasm | Cytoplasm | Cell division |
Leishmania is a parasitic protozoan, a single-celled organism of the genus Leishmania that are responsible for the disease leishmaniasis. They are spread by sandflies of the genus Phlebotomus in the Old World, and of the genus Lutzomyia in the New World. At least 93 sandfly species are proven or probable vectors worldwide. Their primary hosts are vertebrates; Leishmania commonly infects hyraxes, canids, rodents, and humans.
Virusoids are circular single-stranded RNA(s) dependent on viruses for replication and encapsidation. The genome of virusoids consist of several hundred (200–400) nucleotides and does not code for any proteins.
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Poxviridae is a family of double-stranded DNA viruses. Vertebrates and arthropods serve as natural hosts. There are currently 83 species in this family, divided among 22 genera, which are divided into two subfamilies. Diseases associated with this family include smallpox.
Cystovirus is a genus of double-stranded RNA viruses which infects bacteria. It is the only genus in the family Cystoviridae. The name of the group cysto derives from Greek kystis which means bladder or sack. There are seven species in this genus.
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Lutzomyia is a genus of phlebotomine sand flies consisting of nearly 400 species, at least 33 of which have medical importance as vectors of human disease. Species of the genus Lutzomyia are found only in the New World, distributed in southern areas of the Nearctic and throughout the Neotropical realm. Lutzomyia is one of the two genera of the subfamily Phlebotominae to transmit the Leishmania parasite, with the other being Phlebotomus, found only in the Old World. Lutzomyia sand flies also serve as vectors for the bacterial Carrion's disease and a number of arboviruses.
Leishmania infantum is the causative agent of infantile visceral leishmaniasis in the Mediterranean region and in Latin America, where it has been called Leishmania chagasi. It is also an unusual cause of cutaneous leishmaniasis, which is normally caused by specific lineages. Wild canids and domestic dogs are the natural reservoir of this organism. The sandfly species Lutzomyia longipalpis serves as the primary vector for the transmission of the disease.
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.
Double-stranded RNA viruses are a polyphyletic group of viruses that have double-stranded genomes made of ribonucleic acid. The double-stranded genome is used to transcribe a positive-strand RNA by the viral RNA-dependent RNA polymerase (RdRp). The positive-strand RNA may be used as messenger RNA (mRNA) which can be translated into viral proteins by the host cell's ribosomes. The positive-strand RNA can also be replicated by the RdRp to create a new double-stranded viral genome.
Canine leishmaniasis (LEESH-ma-NIGH-ah-sis) is a zoonotic disease caused by Leishmania parasites transmitted by the bite of an infected phlebotomine sandfly. Canine leishmaniasis was first identified in Europe in 1903, and in 1940, 40% of all dogs in Rome were determined to be positive for leishmaniasis. Traditionally thought of as a disease only found near the Mediterranean basin, 2008 research claims new findings are evidence that canine leishmaniasis is currently expanding in continental climate areas of northwestern Italy, far from the recognized disease-endemic areas along the Mediterranean coasts. Cases of leishmaniasis began appearing in North America in 2000, and, as of 2008, Leishmania-positive foxhounds have been reported in 22 U.S. states and two Canadian provinces.
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Mimivirus-dependent virus Sputnik is a subviral agent that reproduces in amoeba cells that are already infected by a certain helper virus; Sputnik uses the helper virus's machinery for reproduction and inhibits replication of the helper virus. It is known as a virophage, in analogy to the term bacteriophage.
This glossary of virology is a list of definitions of terms and concepts used in virology, the study of viruses, particularly in the description of viruses and their actions. Related fields include microbiology, molecular biology, and genetics.
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Entebbe bat virus is an infectious disease caused by a Flavivirus that is closely related to yellow fever.
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