The Experts below are selected from a list of 1908 Experts worldwide ranked by ideXlab platform
Jussi Hepojoki - One of the best experts on this subject based on the ideXlab platform.
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Snake Deltavirus Utilizes Envelope Proteins of Different Viruses To Generate Infectious Particles
mBio, 2020Co-Authors: Leonóra Szirovicza, Udo Hetzel, Olli Vapalahti, Anja Kipar, Luis Martínez-sobrido, Jussi HepojokiAbstract:Satellite Viruses, most commonly found in plants, rely on helper Viruses to complete their replication cycle. The only known example of a human Satellite virus is the hepatitis D virus (HDV), and it is generally thought to require hepatitis B virus (HBV) to form infectious particles. Until 2018, HDV was the sole representative of the genus Deltavirus and was thought to have evolved in humans, the only known HDV host. The subsequent identification of HDV-like agents in birds, snakes, fish, amphibians, and invertebrates indicated that the evolutionary history of deltaViruses is likely much longer than previously hypothesized. Interestingly, none of the HDV-like agents were found in coinfection with an HBV-like agent, suggesting that these Viruses use different helper virus(es). Here we show, using snake deltavirus (SDeV), that HBV and hepadnaViruses represent only one example of helper Viruses for deltaViruses. We cloned the SDeV genome into a mammalian expression plasmid, and by transfection could initiate SDeV replication in cultured snake and mammalian cell lines. By superinfecting persistently SDeV-infected cells with reptarenaViruses and hartmaniViruses, or by transfecting their surface proteins, we could induce production of infectious SDeV particles. Our findings indicate that deltaViruses can likely use a multitude of helper Viruses or even viral glycoproteins to form infectious particles. This suggests that persistent infections, such as those caused by arenaViruses and orthohantaViruses used in this study, and recurrent infections would be beneficial for the spread of deltaViruses. It seems plausible that further human or animal disease associations with deltavirus infections will be identified in the future.IMPORTANCE DeltaViruses need a coinfecting enveloped virus to produce infectious particles necessary for transmission to a new host. Hepatitis D virus (HDV), the only known deltavirus until 2018, has been found only in humans, and its coinfection with hepatitis B virus (HBV) is linked with fulminant hepatitis. The recent discovery of deltaViruses without a coinfecting HBV-like agent in several different taxa suggested that deltaViruses could employ coinfection by other enveloped Viruses to complete their life cycle. In this report, we show that snake deltavirus (SDeV) efficiently utilizes coinfecting reptarena- and hartmaniViruses to form infectious particles. Furthermore, we demonstrate that cells expressing the envelope proteins of arenaViruses and orthohantaViruses produce infectious SDeV particles. As the envelope proteins are responsible for binding and infecting new host cells, our findings indicate that deltaViruses are likely not restricted in their tissue tropism, implying that they could be linked to animal or human diseases other than hepatitis.
Marc Cornelissen - One of the best experts on this subject based on the ideXlab platform.
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Expression of tobacco necrosis virus open reading frames 1 and 2 is sufficient for the replication of Satellite tobacco necrosis virus
Virology, 1995Co-Authors: Marco Andriessen, Frank Meulewaeter, Marc CornelissenAbstract:Tobacco necrosis virus (TNV) is a small icosahedral plant virus which is often associated with Satellite Viruses. The genomic RNA of TNV contains six open reading frames (ORFs), of which ORFs 1 and 2 are thought to encode the viral polymerase. We demonstrate that tobacco protoplasts transfected with a vector containing TNV ORFs 1 and 2 under the control of the cauliflower mosaic virus 35S promoter, as well as protoplasts derived from transgenic Nicotiana tabacum containing the same gene(s), support replication of Satellite tobacco necrosis virus RNA.
Matthias G. Fischer - One of the best experts on this subject based on the ideXlab platform.
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A classification system for virophages and Satellite Viruses
Archives of Virology, 2016Co-Authors: Mart Krupovic, Jens H. Kuhn, Matthias G. FischerAbstract:Satellite Viruses encode structural proteins required for the formation of infectious particles but depend on helper Viruses for completing their replication cycles. Because of this unique property, Satellite Viruses that infect plants, arthropods, or mammals, as well as the more recently discovered Satellite-like Viruses that infect protists (virophages), have been grouped with other, so-called “sub-viral agents.” For the most part, Satellite Viruses are therefore not classified. We argue that possession of a coat-protein-encoding gene and the ability to form virions are the defining features of a bona fide virus. Accordingly, all Satellite Viruses and virophages should be consistently classified within appropriate taxa. We propose to create four new genera — Albetovirus , Aumaivirus , Papanivirus , and Virtovirus — for positive-sense single-stranded (+) RNA Satellite Viruses that infect plants and the family Sarthroviridae , including the genus Macronovirus , for (+)RNA Satellite Viruses that infect arthopods. For double-stranded DNA virophages, we propose to establish the family Lavidaviridae , including two genera, Sputnikvirus and Mavirus .
Leonóra Szirovicza - One of the best experts on this subject based on the ideXlab platform.
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Snake Deltavirus Utilizes Envelope Proteins of Different Viruses To Generate Infectious Particles
mBio, 2020Co-Authors: Leonóra Szirovicza, Udo Hetzel, Olli Vapalahti, Anja Kipar, Luis Martínez-sobrido, Jussi HepojokiAbstract:Satellite Viruses, most commonly found in plants, rely on helper Viruses to complete their replication cycle. The only known example of a human Satellite virus is the hepatitis D virus (HDV), and it is generally thought to require hepatitis B virus (HBV) to form infectious particles. Until 2018, HDV was the sole representative of the genus Deltavirus and was thought to have evolved in humans, the only known HDV host. The subsequent identification of HDV-like agents in birds, snakes, fish, amphibians, and invertebrates indicated that the evolutionary history of deltaViruses is likely much longer than previously hypothesized. Interestingly, none of the HDV-like agents were found in coinfection with an HBV-like agent, suggesting that these Viruses use different helper virus(es). Here we show, using snake deltavirus (SDeV), that HBV and hepadnaViruses represent only one example of helper Viruses for deltaViruses. We cloned the SDeV genome into a mammalian expression plasmid, and by transfection could initiate SDeV replication in cultured snake and mammalian cell lines. By superinfecting persistently SDeV-infected cells with reptarenaViruses and hartmaniViruses, or by transfecting their surface proteins, we could induce production of infectious SDeV particles. Our findings indicate that deltaViruses can likely use a multitude of helper Viruses or even viral glycoproteins to form infectious particles. This suggests that persistent infections, such as those caused by arenaViruses and orthohantaViruses used in this study, and recurrent infections would be beneficial for the spread of deltaViruses. It seems plausible that further human or animal disease associations with deltavirus infections will be identified in the future.IMPORTANCE DeltaViruses need a coinfecting enveloped virus to produce infectious particles necessary for transmission to a new host. Hepatitis D virus (HDV), the only known deltavirus until 2018, has been found only in humans, and its coinfection with hepatitis B virus (HBV) is linked with fulminant hepatitis. The recent discovery of deltaViruses without a coinfecting HBV-like agent in several different taxa suggested that deltaViruses could employ coinfection by other enveloped Viruses to complete their life cycle. In this report, we show that snake deltavirus (SDeV) efficiently utilizes coinfecting reptarena- and hartmaniViruses to form infectious particles. Furthermore, we demonstrate that cells expressing the envelope proteins of arenaViruses and orthohantaViruses produce infectious SDeV particles. As the envelope proteins are responsible for binding and infecting new host cells, our findings indicate that deltaViruses are likely not restricted in their tissue tropism, implying that they could be linked to animal or human diseases other than hepatitis.
Marco Andriessen - One of the best experts on this subject based on the ideXlab platform.
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Expression of tobacco necrosis virus open reading frames 1 and 2 is sufficient for the replication of Satellite tobacco necrosis virus
Virology, 1995Co-Authors: Marco Andriessen, Frank Meulewaeter, Marc CornelissenAbstract:Tobacco necrosis virus (TNV) is a small icosahedral plant virus which is often associated with Satellite Viruses. The genomic RNA of TNV contains six open reading frames (ORFs), of which ORFs 1 and 2 are thought to encode the viral polymerase. We demonstrate that tobacco protoplasts transfected with a vector containing TNV ORFs 1 and 2 under the control of the cauliflower mosaic virus 35S promoter, as well as protoplasts derived from transgenic Nicotiana tabacum containing the same gene(s), support replication of Satellite tobacco necrosis virus RNA.
