Plant virus

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Pepper mild mottle virus Pepper mild mottle virus.png
Pepper mild mottle virus
Leaf curl virus SequoiaBio Leaf Curl.jpg
Leaf curl 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").

Contents

Most 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 figures relate only to cultivated plants, which represent only a tiny fraction of the total number of plant species. Viruses in wild plants have not been well-studied, but the interactions between wild plants and their viruses often do not appear to cause disease in the host plants. [1]

To transmit from one plant to another and from one plant cell to another, plant viruses must use strategies that are usually different from animal viruses. Most plants do not move, and so plant-to-plant transmission usually involves vectors (such as insects). Plant cells are surrounded by solid cell walls, therefore transport through plasmodesmata is the preferred path for virions to move between plant cells. Plants have specialized mechanisms for transporting mRNAs through plasmodesmata, and these mechanisms are thought to be used by RNA viruses to spread from one cell to another. [2] Plant defenses against viral infection include, among other measures, the use of siRNA in response to dsRNA. [3] Most plant viruses encode a protein to suppress this response. [4] Plants also reduce transport through plasmodesmata in response to injury. [2]

History

Electron micrograph of the rod-shaped particles of tobacco mosaic virus TobaccoMosaicVirus.jpg
Electron micrograph of the rod-shaped particles of tobacco mosaic virus

The discovery of plant viruses causing disease is often accredited to A. Mayer (1886) working in the Netherlands demonstrated that the sap of mosaic obtained from tobacco leaves developed mosaic symptom when injected in healthy plants. However the infection of the sap was destroyed when it was boiled. He thought that the causal agent was bacteria. However, after larger inoculation with a large number of bacteria, he failed to develop a mosaic symptom.

In 1898, Martinus Beijerinck, who was a professor of microbiology at the Technical University the Netherlands, put forth his concepts that viruses were small and determined that the "mosaic disease" remained infectious when passed through a Chamberland filter-candle. This was in contrast to bacteria microorganisms, which were retained by the filter. Beijerinck referred to the infectious filtrate as a "contagium vivum fluidum", thus the coinage of the modern term "virus".

After the initial discovery of the 'viral concept' there was need to classify any other known viral diseases based on the mode of transmission even though microscopic observation proved fruitless. In 1939 Holmes published a classification list of 129 plant viruses. This was expanded and in 1999 there were 977 officially recognized, and some provisional, plant virus species.

The purification (crystallization) of TMV was first performed by Wendell Stanley, who published his findings in 1935, although he did not determine that the RNA was the infectious material. However, he received the Nobel Prize in Chemistry in 1946. In the 1950s a discovery by two labs simultaneously proved that the purified RNA of the TMV was infectious which reinforced the argument. The RNA carries genetic information to code for the production of new infectious particles.

More recently virus research has been focused on understanding the genetics and molecular biology of plant virus genomes, with a particular interest in determining how the virus can replicate, move and infect plants. Understanding the virus genetics and protein functions has been used to explore the potential for commercial use by biotechnology companies. In particular, viral-derived sequences have been used to provide an understanding of novel forms of resistance. The recent boom in technology allowing humans to manipulate plant viruses may provide new strategies for production of value-added proteins in plants.

Structure

Structural comparison of some plant viruses Molecules-23-02311-g001.png
Structural comparison of some plant viruses

Viruses are so small that they can only be observed under an electron microscope. The structure of a virus is given by its coat of proteins, which surround the viral genome. Assembly of viral particles takes place spontaneously.

Over 50% of known plant viruses are rod-shaped (flexuous or rigid). The length of the particle is normally dependent on the genome but it is usually between 300 and 500 nm with a diameter of 15–20 nm. Protein subunits can be placed around the circumference of a circle to form a disc. In the presence of the viral genome, the discs are stacked, then a tube is created with room for the nucleic acid genome in the middle. [5]

The second most common structure amongst plant viruses are isometric particles. They are 25–50 nm in diameter. In cases when there is only a single coat protein, the basic structure consists of 60 T subunits, where T is an integer. Some viruses may have 2 coat proteins that associate to form an icosahedral shaped particle.

There are three genera of Geminiviridae that consist of particles that are like two isometric particles stuck together.

A few number of plant viruses have, in addition to their coat proteins, a lipid envelope. This is derived from the plant cell membrane as the virus particle buds off from the cell.

Transmission

Through sap

Viruses can be spread by direct transfer of sap by contact of a wounded plant with a healthy one. Such contact may occur during agricultural practices, as by damage caused by tools or hands, or naturally, as by an animal feeding on the plant. Generally TMV, potato viruses and cucumber mosaic viruses are transmitted via sap.

By insects

Plant virus transmission strategies in insect vectors Viruses-08-00303-g001.png
Plant virus transmission strategies in insect vectors

Plant viruses need to be transmitted by a vector, most often insects such as leafhoppers. One class of viruses, the Rhabdoviridae, has been proposed to actually be insect viruses that have evolved to replicate in plants. The chosen insect vector of a plant virus will often be the determining factor in that virus's host range: it can only infect plants that the insect vector feeds upon. This was shown in part when the old world white fly made it to the United States, where it transferred many plant viruses into new hosts. Depending on the way they are transmitted, plant viruses are classified as non-persistent, semi-persistent and persistent. In non-persistent transmission, viruses become attached to the distal tip of the stylet of the insect and on the next plant it feeds on, it inoculates it with the virus. [6] Semi-persistent viral transmission involves the virus entering the foregut of the insect. Those viruses that manage to pass through the gut into the haemolymph and then to the salivary glands are known as persistent. There are two sub-classes of persistent viruses: propagative and circulative. Propagative viruses are able to replicate in both the plant and the insect (and may have originally been insect viruses), whereas circulative can not. Circulative viruses are protected inside aphids by the chaperone protein symbionin, produced by bacterial symbionts. Many plant viruses encode within their genome polypeptides with domains essential for transmission by insects. In non-persistent and semi-persistent viruses, these domains are in the coat protein and another protein known as the helper component. A bridging hypothesis has been proposed to explain how these proteins aid in insect-mediated viral transmission. The helper component will bind to the specific domain of the coat protein, and then the insect mouthparts – creating a bridge. In persistent propagative viruses, such as tomato spotted wilt virus (TSWV), there is often a lipid coat surrounding the proteins that is not seen in other classes of plant viruses. In the case of TSWV, 2 viral proteins are expressed in this lipid envelope. It has been proposed that the viruses bind via these proteins and are then taken into the insect cell by receptor-mediated endocytosis.

By nematodes

Soil-borne nematodes have been shown to transmit viruses. They acquire and transmit them by feeding on infected roots. Viruses can be transmitted both non-persistently and persistently, but there is no evidence of viruses being able to replicate in nematodes. The virions attach to the stylet (feeding organ) or to the gut when they feed on an infected plant and can then detach during later feeding to infect other plants. Nematodes transmit viruses such as tobacco ringspot virus and tobacco rattle virus. [7]

By plasmodiophorids

A number of virus genera are transmitted, both persistently and non-persistently, by soil borne zoosporic protozoa. These protozoa are not phytopathogenic themselves, but parasitic. Transmission of the virus takes place when they become associated with the plant roots. Examples include Polymyxa graminis , which has been shown to transmit plant viral diseases in cereal crops [8] and Polymyxa betae which transmits Beet necrotic yellow vein virus. Plasmodiophorids also create wounds in the plant's root through which other viruses can enter.

On seed and pollen

Plant virus transmission from generation to generation occurs in about 20% of plant viruses. When viruses are transmitted by seeds, the seed is infected in the generative cells and the virus is maintained in the germ cells and sometimes, but less often, in the seed coat. When the growth and development of plants is delayed because of situations like unfavorable weather, there is an increase in the amount of virus infections in seeds. There does not seem to be a correlation between the location of the seed on the plant and its chances of being infected. Little is known about the mechanisms involved in the transmission of plant viruses via seeds, although it is known that it is environmentally influenced and that seed transmission occurs because of a direct invasion of the embryo via the ovule or by an indirect route with an attack on the embryo mediated by infected gametes. These processes can occur concurrently or separately depending on the host plant. It is unknown how the virus is able to directly invade and cross the embryo and boundary between the parental and progeny generations in the ovule. Many plants species can be infected through seeds including but not limited to the families Leguminosae, Solanaceae, Compositae, Rosaceae, Cucurbitaceae, Gramineae. Bean common mosaic virus is transmitted through seeds.

Directly from plant to humans

There is tenuous evidence that a virus common to peppers, the Pepper Mild Mottle Virus (PMMoV) may have moved on to infect humans. [9] This is a rare and unlikely event as, to enter a cell and replicate, a virus must "bind to a receptor on its surface, and a plant virus would be highly unlikely to recognize a receptor on a human cell. One possibility is that the virus does not infect human cells directly. Instead, the naked viral RNA may alter the function of the cells through a mechanism similar to RNA interference, in which the presence of certain RNA sequences can turn genes on and off," according to Virologist Robert Garry. [10]

Effects on hosts

The intracellular life of plant viruses in hosts is still understudied especially the earliest stages of infection. [11] Many membranous structures which viruses induce plant cells to produce are motile, often being used to traffic new virions within the producing cell and into their neighbors. [11] Viruses also induce various changes to plants' own intracellular membranes. [11] The work of Perera et al. 2012 in mosquito virus infection and various others studying yeast models of plant viruses find this to be due to changes in homeostasis of the lipids that compose their intracellular membranes, including increasing synthesis. [11] These comparable lipid alterations inform our expectations and research directions for the lesser understood area of plant viruses. [11]

Translation of plant viral proteins

Polyprotein processing is used by 45% of plant viruses. Plant virus families that produce polyproteins, their genomes, and colored triangles indicating self-cleavage sites. Fpls-09-00666-g002.jpg
Polyprotein processing is used by 45% of plant viruses. Plant virus families that produce polyproteins, their genomes, and colored triangles indicating self-cleavage sites.

75% of plant viruses have genomes that consist of single stranded RNA (ssRNA). 65% of plant viruses have +ssRNA, meaning that they are in the same sense orientation as messenger RNA but 10% have -ssRNA, meaning they must be converted to +ssRNA before they can be translated. 5% are double stranded RNA and so can be immediately translated as +ssRNA viruses. 3% require a reverse transcriptase enzyme to convert between RNA and DNA. 17% of plant viruses are ssDNA and very few are dsDNA, in contrast a quarter of animal viruses are dsDNA and three-quarters of bacteriophage are dsDNA. [13] Viruses use the plant ribosomes to produce the 4-10 proteins encoded by their genome. However, since many of the proteins are encoded on a single strand (that is, they are polycistronic) this will mean that the ribosome will either only produce one protein, as it will terminate translation at the first stop codon, or that a polyprotein will be produced. Plant viruses have had to evolve special techniques to allow the production of viral proteins by plant cells.

5' Cap

For translation to occur, eukaryotic mRNAs require a 5' Cap structure. This means that viruses must also have one. This normally consists of 7MeGpppN where N is normally adenine or guanine. The viruses encode a protein, normally a replicase, with a methyltransferase activity to allow this.

Some viruses are cap-snatchers. During this process, a 7mG-capped host mRNA is recruited by the viral transcriptase complex and subsequently cleaved by a virally encoded endonuclease. The resulting capped leader RNA is used to prime transcription on the viral genome. [14]

However some plant viruses do not use cap, yet translate efficiently due to cap-independent translation enhancers present in 5' and 3' untranslated regions of viral mRNA. [15]

Readthrough

Some viruses (e.g. tobacco mosaic virus (TMV)) have RNA sequences that contain a "leaky" stop codon. In TMV 95% of the time the host ribosome will terminate the synthesis of the polypeptide at this codon but the rest of the time it continues past it. This means that 5% of the proteins produced are larger than and different from the others normally produced, which is a form of translational regulation. In TMV, this extra sequence of polypeptide is an RNA polymerase that replicates its genome.

Production of sub-genomic RNAs

Some viruses use the production of subgenomic RNAs to ensure the translation of all proteins within their genomes. In this process the first protein encoded on the genome, and is the first to be translated, is a replicase. This protein will act on the rest of the genome producing negative strand sub-genomic RNAs then act upon these to form positive strand sub-genomic RNAs that are essentially mRNAs ready for translation.

Segmented genomes

Some viral families, such as the Bromoviridae instead opt to have multipartite genomes, genomes split between multiple viral particles. For infection to occur, the plant must be infected with all particles across the genome. For instance Brome mosaic virus has a genome split between 3 viral particles, and all 3 particles with the different RNAs are required for infection to take place.

Polyprotein processing

Polyprotein processing is adopted by 45% of plant viruses, such as the Potyviridae and Tymoviridae. [12] The ribosome translates a single protein from the viral genome. Within the polyprotein is an enzyme (or enzymes) with proteinase function that is able to cleave the polyprotein into the various single proteins or just cleave away the protease, which can then cleave other polypeptides producing the mature proteins.

Genome packaging

Besides involvement in the infection process, viral replicase is a directly necessary part of the packaging of RNA viruses' genetic material. This was expected due to replicase involvement already being confirmed in various other viruses. [16]

Applications of plant viruses

Plant viruses can be used to engineer viral vectors, tools commonly used by molecular biologists to deliver genetic material into plant cells; they are also sources of biomaterials and nanotechnology devices. [17] [18] Knowledge of plant viruses and their components has been instrumental for the development of modern plant biotechnology. The use of plant viruses to enhance the beauty of ornamental plants can be considered the first recorded application of plant viruses. Tulip breaking virus is famous for its dramatic effects on the color of the tulip perianth, an effect highly sought after during the 17th-century Dutch "tulip mania." Tobacco mosaic virus (TMV) and cauliflower mosaic virus (CaMV) are frequently used in plant molecular biology. Of special interest is the CaMV 35S promoter, which is a very strong promoter most frequently used in plant transformations. Viral vectors based on tobacco mosaic virus include those of the magnICON® and TRBO plant expression technologies. [18]

Application of plant viruses to enhance the plant beauty. The Semper Augustus, famous for being the most expensive tulip sold during tulip mania. The effects of tulip breaking virus are seen in the striking streaks of white in its red petals. Semper Augustus Tulip 17th century.jpg
Application of plant viruses to enhance the plant beauty. The Semper Augustus, famous for being the most expensive tulip sold during tulip mania. The effects of tulip breaking virus are seen in the striking streaks of white in its red petals.

Building on the market approvals and sales of recombinant virus-based biopharmaceuticals for veterinary and human medicine, the use of engineered plant viruses has been proposed to enhance crop performance and promote sustainable production. [19]

Representative applications of plant viruses are listed below.

Applications of plant viruses [17]
UseDescriptionReferences
Enhanced plant aestheticsIncrease beauty and commercial value of ornamental plants [20]
Cross‐protectionDelivery of mild virus strains to prevent infections by their severe relatives [21]
Weed biocontrolViruses triggering lethal systemic necrosis as bioherbicides [22]
Pest biocontrolEnhanced toxin and pesticide delivery for insect and nematode control [23]
Nanoparticle scaffoldsVirion surfaces are functionalized and used to assemble nanoparticles [24]
NanocarriersVirions are used to transport cargo compounds [25]
Nanoreactors Enzymes are encapsulated into virions to engineer cascade reactions [26]
Recombinant protein/peptide expressionFast, transient overproduction of recombinant peptide, polypeptide libraries and protein complexes [27]
Functional genomic studiesTargeted gene silencing using VIGS and miRNA viral vectors [28]
Genome editing Targeted genome editing via transient delivery of sequence‐specific nucleases [29] [30]
Metabolic pathway engineeringBiosynthetic pathway rewiring to improve production of native and foreign metabolites [31] [32]
Flowering inductionViral expression of FLOWERING LOCUS T to accelerate flowering induction and crop breeding [33]
Crop gene therapy Open‐field use of viral vectors for transient reprogramming of crop traits within a single growing season [19] [34]

See also

Related Research Articles

<span class="mw-page-title-main">Tobacco mosaic virus</span> Virus affecting plants of the Solanaceae family

Tobacco mosaic virus (TMV) is a positive-sense single-stranded RNA virus species in the genus Tobamovirus that infects a wide range of plants, especially tobacco and other members of the family Solanaceae. The infection causes characteristic patterns, such as "mosaic"-like mottling and discoloration on the leaves. TMV was the first virus to be discovered. Although it was known from the late 19th century that a non-bacterial infectious disease was damaging tobacco crops, it was not until 1930 that the infectious agent was determined to be a virus. It is the first pathogen identified as a virus. The virus was crystallised by Wendell Meredith Stanley. It has a similar size to the largest synthetic molecule, known as PG5.

<span class="mw-page-title-main">Sedoreoviridae</span> Family of viruses

Sedoreoviridae is a family of double-stranded RNA viruses. Member viruses have a wide host range, including vertebrates, invertebrates, plants, protists and fungi. They lack lipid envelopes and package their segmented genome within multi-layered capsids. Lack of a lipid envelope has allowed three-dimensional structures of these large complex viruses to be obtained, revealing a structural and likely evolutionary relationship to the cystovirus family of bacteriophage. There are currently 97 species in this family, divided among 15 genera in two subfamilies. Reoviruses can affect the gastrointestinal system and respiratory tract. The name "reo-" is an acronym for "respiratory enteric orphan" viruses. The term "orphan virus" refers to the fact that some of these viruses have been observed not associated with any known disease. Even though viruses in the family Reoviridae have more recently been identified with various diseases, the original name is still used.

Cauliflower mosaic virus (CaMV) is a member of the genus Caulimovirus, one of the six genera in the family Caulimoviridae, which are pararetroviruses that infect plants. Pararetroviruses replicate through reverse transcription just like retroviruses, but the viral particles contain DNA instead of RNA.

<i>Geminiviridae</i> Family of viruses

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.

<i>Tomato bushy stunt virus</i> Species of virus

Tomato bushy stunt virus (TBSV) is a virus of the tombusvirus family. It was first reported in tomatoes in 1935 and primarily affects vegetable crops, though it is not generally considered an economically significant plant pathogen. Depending upon the host, TBSV causes stunting of growth, leaf mottling, and deformed or absent fruit. The virus is likely to be soil-borne in the natural setting, but can also be transmitted mechanically, for example through contaminated cutting tools. TBSV has been used as a model system in virology research on the life cycle of plant viruses, particularly in experimental infections of the model host plant Nicotiana benthamiana.

<span class="mw-page-title-main">Movement protein</span>

A movement protein (MP) is a specific virus-encoded protein that is thought to be a general feature of plant genomes. For a virus to infect a plant, it must be able to move between cells so it can spread throughout the plant. Plant cell walls make this moving/spreading quite difficult and therefore, for this to occur, movement proteins must be present. Movement proteins allow for local and systemic viral spread throughout a plant. MPs were first studied in the Tobacco Mosaic Virus (TMV), where it was found that viruses were unable to spread without the presence of a specific protein. In general, the plant viruses first move within the cell from replication sites to the plasmodesmata (PD). Then, the virus can go through the PD and spread to other cells. This process is controlled through MPs. Different MPs use different mechanisms and pathways to regulate the spread of some viruses. Nearly all plants express at least one MP, while some can encode many different MPs which help with cell-to-cell viral transmission. They serve to increase the size exclusion limits (SEL) of plasmodesmata to allow for greater spread of the virus.

<i>Potyvirus</i> Genus of positive-strand RNA viruses in the family Potyviridae

Potyvirus is a genus of positive-strand RNA viruses in the family Potyviridae. Plants serve as natural hosts. Like begomoviruses, members of this genus may cause significant losses in agricultural, pastoral, horticultural, and ornamental crops. More than 200 species of aphids spread potyviruses, and most are from the subfamily Aphidinae. The genus contains 190 species and potyviruses account for about thirty percent of all currently known plant viruses.

<span class="mw-page-title-main">Viroplasm</span>

A viroplasm, sometimes called "virus factory" or "virus inclusion", is an inclusion body in a cell where viral replication and assembly occurs. They may be thought of as viral factories in the cell. There are many viroplasms in one infected cell, where they appear dense to electron microscopy. Very little is understood about the mechanism of viroplasm formation.

<i>Cowpea chlorotic mottle virus</i> Species of virus

Cowpea chlorotic mottle virus, known by the abbreviation CCMV, is a virus that specifically infects the cowpea plant, or black-eyed pea. The leaves of infected plants develop yellow spots, hence the name "chlorotic". Similar to its "brother" virus, Cowpea mosaic virus (CPMV), CCMV is produced in high yield in plants. In the natural host, viral particles can be produced at 1–2 mg per gram of infected leaf tissue. Belonging to the bromovirus genus, cowpea chlorotic mottle virus (CCMV) is a small spherical plant virus. Other members of this genus include the brome mosaic virus (BMV) and the broad bean mottle virus (BBMV).

<i>Alfalfa mosaic virus</i> Species of virus

Alfalfa mosaic virus (AMV), also known as Lucerne mosaic virus or Potato calico virus, is a worldwide distributed phytopathogen that can lead to necrosis and yellow mosaics on a large variety of plant species, including commercially important crops. It is the only Alfamovirus of the family Bromoviridae. In 1931 Weimer J.L. was the first to report AMV in alfalfa. Transmission of the virus occurs mainly by some aphids, by seeds or by pollen to the seed.

Rice hoja blanca tenuivirus (RHBV), Spanish for "white leaf rice virus", is a plant virus in the family Phenuiviridae. RHBV causes Hoja blanca disease (HBD), which affects the leaves of the rice plant Oryza sativa, stunting the growth of the plant or killing it altogether. RHBV is carried by an insect vector, Tagosodes orizicolus, a type of planthopper. The virus is found in South America, Mexico, throughout Central America, the Caribbean region, and the southern United States. In South America, the disease is endemic to Colombia, Venezuela, Ecuador, Peru, Suriname, French Guiana and Guyana.

<i>Cucumber mosaic virus</i> Species of virus

Cucumber mosaic virus (CMV) is a plant pathogenic virus in the family Bromoviridae. This virus has a worldwide distribution and a very wide host range, having the reputation of the widest host range of any known plant virus. It can be transmitted from plant to plant both mechanically by sap and by aphids in a stylet-borne fashion. It can also be transmitted in seeds and by the parasitic weeds, Cuscuta sp. (dodder).

Tomato yellow leaf curl virus (TYLCV) is a DNA virus from the genus Begomovirus and the family Geminiviridae. TYLCV causes the most destructive disease of tomato, and it can be found in tropical and subtropical regions causing severe economic losses. This virus is transmitted by an insect vector from the family Aleyrodidae and order Hemiptera, the whitefly Bemisia tabaci, commonly known as the silverleaf whitefly or the sweet potato whitefly. The primary host for TYLCV is the tomato plant, and other plant hosts where TYLCV infection has been found include eggplants, potatoes, tobacco, beans, and peppers. Due to the rapid spread of TYLCV in the last few decades, there is an increased focus in research trying to understand and control this damaging pathogen. Some interesting findings include the virus being sexually transmitted from infected males to non-infected females, and an evidence that TYLCV is transovarially transmitted to offspring for two generations.

<span class="mw-page-title-main">Introduction to viruses</span> Non-technical introduction to viruses

A virus is a tiny infectious agent that reproduces inside the cells of living hosts. When infected, the host cell is forced to rapidly produce thousands of identical copies of the original virus. Unlike most living things, viruses do not have cells that divide; new viruses assemble in the infected host cell. But unlike simpler infectious agents like prions, they contain genes, which allow them to mutate and evolve. Over 4,800 species of viruses have been described in detail out of the millions in the environment. Their origin is unclear: some may have evolved from plasmids—pieces of DNA that can move between cells—while others may have evolved from bacteria.

<span class="mw-page-title-main">Virus</span> Infectious agent that replicates in cells

A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Viruses are found in almost every ecosystem on Earth and are the most numerous type of biological entity. Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898, more than 11,000 of the millions of virus species have been described in detail. The study of viruses is known as virology, a subspeciality of microbiology.

<i>Carnation Italian ringspot virus</i> Plant virus impacting carnation plants

Carnation Italian Ringspot Virus (CIRV) is a plant virus that impacts carnation plants. These flowers are a popular choice in ornamental flower arrangements. This article will provide an overview of CIRV. This will include the history of the virus, information on transmission, symptoms, and characteristics, and research about how it relates to plant physiology.

Triatoma virus (TrV) is a virus belonging to the insect virus family Dicistroviridae. Within this family, there are currently 3 genera and 15 species of virus. Triatoma virus belongs to the genus Cripavirus. It is non-enveloped and its genetic material is positive-sense, single-stranded RNA. The natural hosts of triatoma virus are invertebrates. TrV is a known pathogen to Triatoma infestans, the major vector of Chagas disease in Argentina which makes triatoma virus a major candidate for biological vector control as opposed to chemical insecticides. Triatoma virus was first discovered in 1984 when a survey of pathogens of triatomes was conducted in the hopes of finding potential biological control methods for T. infestans.

<i>Ground squirrel hepatitis virus</i> Species of virus

Ground squirrel hepatitis virus, abbreviated GSHV, is a partially double-stranded DNA virus that is closely related to human Hepatitis B virus (HBV) and Woodchuck hepatitis virus (WHV). It is a member of the family of viruses Hepadnaviridae and the genus Orthohepadnavirus. Like the other members of its family, GSHV has high degree of species and tissue specificity. It was discovered in Beechey ground squirrels, Spermophilus beecheyi, but also infects Arctic ground squirrels, Spermophilus parryi. Commonalities between GSHV and HBV include morphology, DNA polymerase activity in genome repair, cross-reacting viral antigens, and the resulting persistent infection with viral antigen in the blood (antigenemia). As a result, GSHV is used as an experimental model for HBV.

Carrot virus Y (CarVY) is a (+)ss-RNA virus that affects crops of the carrot family (Apiaceae), such as carrots, anise, chervil, coriander, cumin, dill and parsnip. Carrots are the only known crop to be infected in the field. Infection by the virus leads to deformed roots and discolored or mottled leaves. The virus is spread through insect vectors, and is currently only found in Australia.

<i>Modoc virus</i> Species of virus

Modoc virus (MODV) is a rodent-associated flavivirus. Small and enveloped, MODV contains positive single-stranded RNA. Taxonomically, MODV is part of the Flavivirus genus and Flaviviridae family. The Flavivirus genus includes nearly 80 viruses, both vector-borne and no known vector (NKV) species. Known flavivirus vector-borne viruses include Dengue virus, Yellow Fever virus, tick-borne encephalitis virus, and West Nile virus.

References

  1. Roossinck, Marilyn J. (2011). "The good viruses: viral mutualistic symbioses". Nature Reviews Microbiology. 9 (2): 99–108. doi: 10.1038/nrmicro2491 . PMID   21200397. S2CID   23318905.
  2. 1 2 Oparka, Karl J.; Roberts, Alison G. (1 January 2001). "Plasmodesmata. A Not So Open-and-Shut Case". Plant Physiology. 125 (1): 123–126. doi:10.1104/pp.125.1.123. PMC   1539342 . PMID   11154313.
  3. Alberts, Bruce; Johnson, Alexander; Lewis, Julian; Raff, Martin; Roberts, Keith; Walter, Peter (2002). "7: Control of Gene Expression". Molecular Biology of the Cell. Garland Science. pp. 451–452. ISBN   978-0-8153-3218-3.
  4. Ding, Shou-Wei; Voinnet, Olivier (2007). "Antiviral Immunity Directed by Small RNAs". Cell. 130 (3): 413–426. doi:10.1016/j.cell.2007.07.039. PMC   2703654 . PMID   17693253.
  5. Parvez, Mohammad Khalid (25 August 2020). "Geometric architecture of viruses". World Journal of Virology. 9 (2): 5–18. doi: 10.5501/wjv.v9.i2.5 . PMC   7459239 . PMID   32923381.
  6. Gray, Stewart M.; Banerjee, Nanditta (March 1999). "Mechanisms of Arthropod Transmission of Plant and Animal Viruses". Microbiology and Molecular Biology Reviews. 63 (1): 128–148. doi:10.1128/MMBR.63.1.128-148.1999. PMC   98959 . PMID   10066833.
  7. Verchot-Lubicz, Jeanmarie (2003). "Soilborne viruses: advances in virus movement, virus induced gene silencing, and engineered resistance". Physiological and Molecular Plant Pathology. 62 (2): 56. Bibcode:2003PMPP...62...55V. doi:10.1016/S0885-5765(03)00040-7.
  8. Kanyuka, Konstantin; Ward, Elaine; Adams, Michael J. (2003). "Polymyxa graminis and the cereal viruses it transmits: a research challenge". Molecular Plant Pathology. 4 (5): 393–406. doi: 10.1046/j.1364-3703.2003.00177.x . PMID   20569399.
  9. Aguado-García, Yarenci; Taboada, Blanca; Morán, Patricia; Rivera-Gutiérrez, Xaira; Serrano-Vázquez, Angélica; Iša, Pavel; Rojas-Velázquez, Liliana; Pérez-Juárez, Horacio; López, Susana; Torres, Javier; Ximénez, Cecilia; Arias, Carlos F. (12 August 2020). "Tobamoviruses can be frequently present in the oropharynx and gut of infants during their first year of life". Scientific Reports. 10 (1): 13595. Bibcode:2020NatSR..1013595A. doi:10.1038/s41598-020-70684-w. PMC   7423923 . PMID   32788688.
  10. "Evidence of First Virus That Moves from Plants to Humans". TechVert. 15 April 2010. Archived from the original on 22 April 2010.
  11. 1 2 3 4 5 Laliberté, Jean-François; Zheng, Huanquan (3 November 2014). "Viral Manipulation of Plant Host Membranes". Annual Review of Virology . 1 (1). Annual Reviews: 237–259. doi:10.1146/annurev-virology-031413-085532. ISSN   2327-056X. PMID   26958722.
  12. 1 2 Rodamilans, Bernardo; Shan, Hongying; Pasin, Fabio; García, Juan Antonio (2018). "Plant Viral Proteases: Beyond the Role of Peptide Cutters". Frontiers in Plant Science. 9: 666. doi: 10.3389/fpls.2018.00666 . PMC   5967125 . PMID   29868107.
  13. Hull, Robert (November 2001). "Classifying reverse transcribing elements: a proposal and a challenge to the ICTV". Archives of Virology. 146 (11): 2255–2261. doi: 10.1007/s007050170036 . PMID   11765927. S2CID   23269106.
  14. Duijsings; et al. (2001). "In vivo analysis of the TSWV cap-snatching mechanism: single base complementarity and primer length requirements". The EMBO Journal. 20 (10): 2545–2552. doi:10.1093/emboj/20.10.2545. PMC   125463 . PMID   11350944.
  15. Kneller, Elizabeth L. Pettit; Rakotondrafara, Aurélie M.; Miller, W. Allen (July 2006). "Cap-independent translation of plant viral RNAs". Virus Research. 119 (1): 63–75. doi:10.1016/j.virusres.2005.10.010. PMC   1880899 . PMID   16360925.
  16. Rao, A.L.N. (2006). "Genome Packaging by Spherical Plant RNA Viruses". Annual Review of Phytopathology . 44 (1). Annual Reviews: 61–87. doi:10.1146/annurev.phyto.44.070505.143334. PMID   16480335.
  17. 1 2 Pasin, Fabio; Menzel, Wulf; Daròs, José-Antonio (June 2019). "Harnessed viruses in the age of metagenomics and synthetic biology: an update on infectious clone assembly and biotechnologies of plant viruses". Plant Biotechnology Journal. 17 (6): 1010–1026. doi:10.1111/pbi.13084. ISSN   1467-7652. PMC   6523588 . PMID   30677208.
  18. 1 2 Abrahamian, Peter; Hammond, Rosemarie W.; Hammond, John (10 June 2020). "Plant Virus-Derived Vectors: Applications in Agricultural and Medical Biotechnology". Annual Review of Virology. 7 (1): 513–535. doi: 10.1146/annurev-virology-010720-054958 . ISSN   2327-0578. PMID   32520661. S2CID   219588089.
  19. 1 2 Pasin, Fabio; Uranga, Mireia; Charudattan, Raghavan; Kwon, Choon-Tak (15 May 2024). "Engineering good viruses to improve crop performance". Nature Reviews Bioengineering. 2 (7): 532–534. doi:10.1038/s44222-024-00197-y. ISSN   2731-6092. Full-text free access
  20. Valverde, Rodrigo A.; Sabanadzovic, Sead; Hammond, John (May 2012). "Viruses that Enhance the Aesthetics of Some Ornamental Plants: Beauty or Beast?". Plant Disease. 96 (5): 600–611. doi: 10.1094/PDIS-11-11-0928-FE . ISSN   0191-2917. PMID   30727518.
  21. Ziebell, Heiko; Carr, John Peter (2010). "Cross-protection: a century of mystery". Advances in Virus Research. 76: 211–264. doi:10.1016/S0065-3527(10)76006-1. ISSN   1557-8399. PMID   20965075.
  22. Harding, Dylan P.; Raizada, Manish N. (2015). "Controlling weeds with fungi, bacteria and viruses: a review". Frontiers in Plant Science. 6: 659. doi: 10.3389/fpls.2015.00659 . ISSN   1664-462X. PMC   4551831 . PMID   26379687.
  23. Bonning, Bryony C.; Pal, Narinder; Liu, Sijun; Wang, Zhaohui; Sivakumar, S.; Dixon, Philip M.; King, Glenn F.; Miller, W. Allen (January 2014). "Toxin delivery by the coat protein of an aphid-vectored plant virus provides plant resistance to aphids". Nature Biotechnology. 32 (1): 102–105. doi:10.1038/nbt.2753. ISSN   1546-1696. PMID   24316580. S2CID   7109502.
  24. Steele, John F. C.; Peyret, Hadrien; Saunders, Keith; Castells-Graells, Roger; Marsian, Johanna; Meshcheriakova, Yulia; Lomonossoff, George P. (July 2017). "Synthetic plant virology for nanobiotechnology and nanomedicine". Wiley Interdisciplinary Reviews. Nanomedicine and Nanobiotechnology. 9 (4): e1447. doi:10.1002/wnan.1447. ISSN   1939-0041. PMC   5484280 . PMID   28078770.
  25. Aumiller, William M.; Uchida, Masaki; Douglas, Trevor (21 May 2018). "Protein cage assembly across multiple length scales". Chemical Society Reviews. 47 (10): 3433–3469. doi:10.1039/c7cs00818j. ISSN   1460-4744. PMC   6729141 . PMID   29497713.
  26. Comellas-Aragonès, Marta; Engelkamp, Hans; Claessen, Victor I.; Sommerdijk, Nico A. J. M.; Rowan, Alan E.; Christianen, Peter C. M.; Maan, Jan C.; Verduin, Benedictus J. M.; Cornelissen, Jeroen J. L. M.; Nolte, Roeland J. M. (October 2007). "A virus-based single-enzyme nanoreactor". Nature Nanotechnology. 2 (10): 635–639. Bibcode:2007NatNa...2..635C. doi:10.1038/nnano.2007.299. hdl: 2066/35237 . ISSN   1748-3395. PMID   18654389. S2CID   226798.
  27. Gleba, Yuri Y.; Tusé, Daniel; Giritch, Anatoli (2014). Plant viral vectors for delivery by Agrobacterium. Current Topics in Microbiology and Immunology. Vol. 375. pp. 155–192. doi:10.1007/82_2013_352. ISBN   978-3-642-40828-1. ISSN   0070-217X. PMID   23949286.
  28. Burch-Smith, Tessa M.; Anderson, Jeffrey C.; Martin, Gregory B.; Dinesh-Kumar, S. P. (September 2004). "Applications and advantages of virus-induced gene silencing for gene function studies in plants". The Plant Journal: For Cell and Molecular Biology. 39 (5): 734–746. doi: 10.1111/j.1365-313X.2004.02158.x . ISSN   0960-7412. PMID   15315635.
  29. Zaidi, Syed Shan-E.-Ali; Mansoor, Shahid (2017). "Viral Vectors for Plant Genome Engineering". Frontiers in Plant Science. 8: 539. doi: 10.3389/fpls.2017.00539 . ISSN   1664-462X. PMC   5386974 . PMID   28443125.
  30. Dinesh-Kumar, Savithramma P.; Voytas, Daniel F. (July 2020). "Editing through infection". Nature Plants. 6 (7): 738–739. Bibcode:2020NatPl...6..738D. doi:10.1038/s41477-020-0716-1. ISSN   2055-0278. PMID   32601418. S2CID   220260018.
  31. Kumagai, M. H.; Donson, J.; della-Cioppa, G.; Harvey, D.; Hanley, K.; Grill, L. K. (28 February 1995). "Cytoplasmic inhibition of carotenoid biosynthesis with virus-derived RNA". Proceedings of the National Academy of Sciences of the United States of America. 92 (5): 1679–1683. Bibcode:1995PNAS...92.1679K. doi: 10.1073/pnas.92.5.1679 . ISSN   0027-8424. PMC   42583 . PMID   7878039.
  32. Majer, Eszter; Llorente, Briardo; Rodríguez-Concepción, Manuel; Daròs, José-Antonio (31 January 2017). "Rewiring carotenoid biosynthesis in plants using a viral vector". Scientific Reports. 7: 41645. Bibcode:2017NatSR...741645M. doi:10.1038/srep41645. ISSN   2045-2322. PMC   5282570 . PMID   28139696.
  33. McGarry, Roisin C.; Klocko, Amy L.; Pang, Mingxiong; Strauss, Steven H.; Ayre, Brian G. (January 2017). "Virus-Induced Flowering: An Application of Reproductive Biology to Benefit Plant Research and Breeding". Plant Physiology. 173 (1): 47–55. doi:10.1104/pp.16.01336. ISSN   1532-2548. PMC   5210732 . PMID   27856915.
  34. Torti, Stefano; Schlesier, René; Thümmler, Anka; Bartels, Doreen; Römer, Patrick; Koch, Birgit; Werner, Stefan; Panwar, Vinay; Kanyuka, Kostya; Wirén, Nicolaus von; Jones, Jonathan D. G.; Hause, Gerd; Giritch, Anatoli; Gleba, Yuri (February 2021). "Transient reprogramming of crop plants for agronomic performance". Nature Plants. 7 (2): 159–171. Bibcode:2021NatPl...7..159T. doi:10.1038/s41477-021-00851-y. ISSN   2055-0278. PMID   33594264. S2CID   231945168.

Further reading