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Potyviridae
''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 contains 13 genera that contain 259 species. Structure Potyvirid virions are nonenveloped, flexuous filamentous, rod-shaped particles. The diameter is around 11–20 nm, with a length of 650–950 nm. Genome Genomes are linear and usually nonsegmented, around 8–12kb in length, consisting of positive-sense RNA, which is surrounded by a protein coat made up of a single viral encoded protein called a capsid. All induce the formation of virus inclusion bodies called cylindrical inclusions (‘pinwheels’) in their hosts. These consist of a single protein (about 70 Dalton (unit), kDa) made in their hosts from a single viral genome product. Member viruses encode large polypeptides that are cleaved into mature proteins. In 5'–3' order these proteins are * P1 (a serine protease): 83 kDa * H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potyvirus
''Potyvirus'' is a genus of positive-strand RNA viruses (named after its type species, potato virus Y, Potato virus Y (''Potyvirus yituberosi,'' PVY)'')'' in the family ''Potyviridae''. Plants serve as natural hosts. Like begomoviruses, members of this genus may cause significant losses in agricultural, pastoral, Horticulture industry, horticultural, and Ornamental plant, ornamental crops. More than 200 species of aphids spread potyviruses, and most are from the subfamily ''Aphidinae'' (genera ''Macrosiphum'' and ''Myzus''). The genus contains 190 species and potyviruses account for about thirty percent of all currently known plant viruses. Structure The virion is Viral envelope, non-enveloped with a flexuous and filamentous Capsid, nucleocapsid, 680 to 900 nanometers (nm) long and is 11–20 nm in diameter. The nucleocapsid contains around 2000 copies of the capsid protein. The symmetry of the nucleocapsid is helical with a pitch of 3.4-3.5 nm. Genome The genome ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ipomovirus
''Ipomovirus'' is a genus of positive-strand RNA viruses in the family ''Potyviridae''. Member viruses infect plants and are transmitted by whiteflies ('' Bemisia tabaci''). The name of the genus is derived from ''Ipomoea'' – the generic name of sweet potato. There are seven species in this genus. Structure Viruses in genus ''Ipomovirus'' are non-enveloped, with flexuous and filamentous geometries. The diameter is around 12–15 nm, and may have a variety of lengths depending on the species (for single segmented species lengths of around 650–900 nm, or for double segmented species 200–300 nm and 500–600 nm). The capsid has helical symmetry with a pitch of 3.4 nm. They induce characteristic inclusion bodies (pinwheels) within infected plant cells. Genome The genome is either monpartite or bipartite depending on the species. Member viruses have linear, single stranded RNA genome of positive polarity about 10-11 kilobases in length. The 3’ terminus h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macluravirus
''Macluravirus'' is a genus of viruses, in the family ''Potyviridae''. Plants serve as natural hosts. There are 11 species in this genus. Description ''Macluravirus'' is characterised by its flexuous filamentous particles, inclusion bodies in infected plant cells and a polyprotein genome strategy. Unlike the other genera it is transmitted by insects. It also has shorter particles (650-660 nm in length). The genomes are monopartite. The name is derived from member species Maclura mosaic virus. History The genus was proposed at the ICTV meeting in San Diego in 1998, and subsequently ratified. Structure Viruses in Macluravirus are non-enveloped, with flexuous and Filamentous geometries. The diameter is around 12-15 nm, with a length of 650-660 nm. Genomes are linear and non-segmented, bipartite, around 8.0kb in length. Life cycle Viral replication is cytoplasmic. Entry into the host cell is achieved by penetration into the host cell. Replication follo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bymovirus
''Bymovirus'' is a genus of viruses, in the family ''Potyviridae ''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 contains 13 genera that contain 259 species. Structure Potyviri ...''. Plants serve as natural hosts. There are six species in this genus. Taxonomy The genus contains the following species, listed by scientific name and followed by the exemplar virus of the species: * ''Bymovirus avenae'', Oat mosaic virus * ''Bymovirus hordei'', Barley mild mosaic virus * ''Bymovirus hordeiluteum'', Barley yellow mosaic virus * ''Bymovirus oryzae'', Rice necrosis mosaic virus * ''Bymovirus tritici'', Wheat spindle streak mosaic virus * ''Bymovirus triticitessellati'', Wheat yellow mosaic virus Structure Viruses in ''Bymovirus'' are non-enveloped, with flexuous and Filamentous geometries. The diameter is around 12-15 nm, with a length o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brambyvirus
''Brambyvirus'' is a genus of viruses, in the family ''Potyviridae ''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 contains 13 genera that contain 259 species. Structure Potyviri ...''. Plants serve as natural hosts. There is only one species in this genus: Blackberry virus Y (''Brambyvirus rubi''). Structure Viruses in ''Brambyvirus'' are non-enveloped, with flexuous and filamentous geometries. The diameter is around 12-15 nm, with a length of 800 nm. Genomes are linear and non-segmented, around 11kb 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. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inosine Triphosphate Pyrophosphatase
Inosine triphosphate pyrophosphatase is an enzyme that in humans is encoded by the ''ITPA'' gene, by the ''rdgB'' gene in bacteria ''E.coli'' and the ''HAM1'' gene in yeast ''S. cerevisiae''; the protein is also encoded by some RNA viruses of the ''Potyviridae'' family. Two transcript variants encoding two different isoforms have been found for this gene. Also, at least two other transcript variants have been identified which are probably regulatory rather than protein-coding. Function The protein encoded by this gene hydrolyzes inosine triphosphate and deoxyinosine triphosphate to the monophosphate nucleotide and diphosphate. The enzyme possesses specificity to multiple substrates, and acts on other nucleotides including xanthosine triphosphate and deoxyxanthosine triphosphate. The encoded protein, which is a member of the HAM1 NTPase protein family, is found in the cytoplasm and acts as a homodimer In biochemistry, a protein dimer is a macromolecular complex or protein mul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Positive-strand RNA Virus
Positive-strand RNA viruses (+ssRNA viruses) are a group of related viruses that have Sense (molecular biology), positive-sense, single-stranded genomes made of ribonucleic acid. The positive-sense genome can act as messenger RNA (mRNA) and can be directly translation (biology), translated into viral proteins by the host cell, host cell's ribosomes. Positive-strand RNA viruses encode an RNA-dependent RNA polymerase (RdRp) which is used during replication of the genome to synthesize a negative-sense antigenome that is then used as a template to create a new positive-sense viral genome. Positive-strand RNA viruses are divided between the phyla ''Kitrinoviricota'', ''Lenarviricota'', and ''Pisuviricota'' (specifically classes ''Pisoniviricetes'' and ''Stelpaviricetes, Stelpavirictes'') all of which are in the kingdom ''Orthornavirae'' and Realm (virology), realm ''Riboviria''. They are Monophyly, monophyletic and descended from a common RNA virus ancestor. In the Baltimore classi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Virus
Plant viruses are viruses that have the potential to affect plants. Like all other viruses, plant viruses are obligate intracellular parasites that do not have the molecular machinery to replicate without a host. Plant viruses can be pathogenic to vascular plants ("higher plants"). Many plant viruses are rod-shaped, with protein discs forming a tube surrounding the viral genome; isometric particles are another common structure. They rarely have an envelope. The great majority have an RNA genome, which is usually small and single stranded (ss), but some viruses have double-stranded (ds) RNA, ssDNA or dsDNA genomes. Although plant viruses are not as well understood as their animal counterparts, one plant virus has become very recognizable: '' tobacco mosaic virus'' (TMV), the first virus to be discovered. This and other viruses cause an estimated US$60 billion loss in crop yields worldwide each year. Plant viruses are grouped into 73 genera and 49 families. However, these fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inclusion Bodies
Inclusion bodies are aggregates of specific types of protein found in neurons, and a number of tissue (biology), tissue cells including red blood cells, bacteria, viruses, and plants. Inclusion bodies of aggregations of multiple proteins are also found in muscle fiber, muscle cells affected by inclusion body myositis and hereditary inclusion body myopathy. Inclusion bodies in neurons may accumulate in the cytoplasm or cell nucleus, nucleus, and are associated with many neurodegenerative diseases. Inclusion bodies in neurodegenerative diseases are protein folding, aggregates of misfolded proteins (aggresomes) and are hallmarks of many of these diseases, including Lewy bodies in dementia with Lewy bodies, and Parkinson's disease, neuroserpin, neuroserpin inclusion bodies called Collins bodies in familial encephalopathy with neuroserpin inclusion bodies, inclusion bodies in Huntington's disease, Papp–Lantos bodies in multiple system atrophy, and various inclusion bodies in frontot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chytrid Fungus
Chytridiomycota are a division of zoosporic organisms in the kingdom Fungi, informally known as chytrids. The name is derived from the Ancient Greek ('), meaning "little pot", describing the structure containing unreleased zoospores. Chytrids are one of the earliest diverging fungal lineages, and their membership in kingdom Fungi is demonstrated with chitin cell walls, a posterior whiplash flagellum, absorptive nutrition, use of glycogen as an energy storage compound, and synthesis of lysine by the -amino adipic acid (AAA) pathway. Chytrids are saprobic, degrading refractory materials such as chitin and keratin, and sometimes act as parasites. There has been a significant increase in the research of chytrids since the discovery of '' Batrachochytrium dendrobatidis'', the causal agent of chytridiomycosis. Classification Species of Chytridiomycota have traditionally been delineated and classified based on development, morphology, substrate, and method of zoospore discharge. Ho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aphid
Aphids are small sap-sucking insects in the Taxonomic rank, family Aphididae. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white Eriosomatinae, woolly aphids. A typical life cycle involves flightless females giving Viviparity, live birth to female Nymph (biology), nymphs—who may also be already Pregnancy, pregnant, an adaptation scientists call telescoping generations—without the involvement of males. Developmental biology, Maturing rapidly, females breed profusely so that the number of these insects multiplies quickly. Alate, Winged females may develop later in the season, allowing the insects to colonize new plants. In Temperate climate, temperate regions, a phase of sexual reproduction occurs in the autumn, with the insects often overwintering as eggs. The life cycle of some species involves an alternation between two species of host plants, for example between an annual crop and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whitefly
Whiteflies are Hemipterans that typically feed on the undersides of plant leaves. They comprise the family Aleyrodidae, the only family in the superfamily Aleyrodoidea. More than 1550 species have been described. Description and taxonomy The Aleyrodidae are a family in the suborder Sternorrhyncha and at present comprise the entire superfamily Aleyrodoidea, related to the superfamily Psylloidea. The family often occurs in older literature as "Aleurodidae", but that is a junior synonym and accordingly incorrect in terms of the international standards for zoological nomenclature. Aleyrodidae are small insects, most species with a wingspan of less than 3 mm and a body length of 1 mm to 2 mm. Many are so small that their size complicates their control in greenhouses because they can only be excluded by screening with very fine mesh; in fact they can enter mesh so fine that many of their natural enemies cannot come in after them, so that unchecked whitefly population ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
