The Experts below are selected from a list of 177 Experts worldwide ranked by ideXlab platform
Nobuhiro Suzuki - One of the best experts on this subject based on the ideXlab platform.
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Viruses of the white root rot fungus rosellinia necatrix
Advances in Virus Research, 2013Co-Authors: Hideki Kondo, Satoko Kanematsu, Nobuhiro SuzukiAbstract:Abstract Rosellinia necatrix is a filamentous ascomycete that is pathogenic to a wide range of perennial plants worldwide. An extensive search for double-stranded RNA of a large collection of field isolates led to the detection of a variety of Viruses. Since the first identification of a reoVirus in this fungus in 2002, several novel Viruses have been molecularly characterized that include members of at least five Virus families. While some cause phenotypic alterations, many others show latent infections. Viruses attenuating the virulence of a host fungus to its plant hosts attract much attention as agents for virocontrol (biological control using Viruses) of the fungus, one of which is currently being tested in experimental fields. Like the Cryphonectria parasitica /Viruses, the R. necatrix /Viruses have emerged as an amenable system for studying Virus/host and Virus/Virus interactions. Several techniques have recently been developed that enhance the investigation of Virus Etiology, replication, and symptom induction in this mycoVirus/fungal host system.
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a novel bipartite double stranded rna mycoVirus from the white root rot fungus rosellinia necatrix molecular and biological characterization taxonomic considerations and potential for biological control
Journal of Virology, 2009Co-Authors: Sotaro Chiba, Satoko Kanematsu, Lakha Salaipeth, Atsuko Sasaki, Nobuhiro SuzukiAbstract:Viruses are found ubiquitously in major groups of filamentous fungi (40), and an increasing number of novel mycoViruses are being reported (3, 36). MycoViruses with RNA genomes are now classified into 10 families, of which four accommodate double-stranded RNA (dsRNA) Viruses and the remaining six comprise single-stranded RNA (ssRNA) Viruses (23). While many ssRNA mycoViruses, like hypoViruses and endornaViruses, do not produce particles, dsRNA Virus genomes, whether undivided (the family Totiviridae) or divided (11 or 12 segments for the family Reoviridae, 4 segments for the family Chrysoviridae, and 2 segments for the family Partitiviridae), are encapsidated in rigid particles. Most mycoViruses are considered to cause cryptic infections, while some cause phenotypic alterations that include hypovirulence and debilitation. However, the lack of artificial introduction methods for most mycoViruses has greatly hampered progress in exploring mycoVirus-host interactions (23, 40). Thus, a Virus Etiology of altered fungal phenotypes was established only for a limited number of examples, including hypoVirus-C. parasitica and mycoreoVirus-C. parasitica. White root rot is one of the most devastating diseases of perennial crops worldwide, particularly highly valued fruits in Japan like apple, Japanese pear, and grapevine. The causal fungus, Rosellinia necatrix, is an ascomycete with a wide range of host plants of >197 species spanning 50 families (31) and is difficult to control by conventional methods, as is often the case for soilborne pathogens. Fungicide application, though it may be effective, is labor-intensive and raises environmental concerns, while cultural practices may not be effective. Successful biocontrol of chestnut blight disease in Europe with hypovirulent strains (25, 38) inspired a group of Japanese researchers to conduct an extensive search of a large collection of >1,000 field fungal isolates for mycoViruses that might serve as virocontrol agents. Virocontrol or virological control refers to one form of biological control utilizing Viruses that infect organisms pathogenic to useful organisms (23). Approximately 20% of the collected isolates of R. necatrix were found to be dsRNA positive and presumed to be infected by mycoViruses (4, 29). Agarose gel profiles of dsRNAs suggested infections by members in the families Totiviridae, Partitiviridae, Reoviridae, and Chrysoviridae, as well as unassigned Viruses (S. Kanematsu and A. Sasaki, unpublished results). Among those dsRNAs, the genomic segments of MycoreoVirus 3 (MyRV3) (55) and Rosellinia necatrix partitiVirus 1 (RnPV1) (44) were well characterized. However, many other dsRNAs remain uncharacterized. Artificial virion introduction protocols, which are often unavailable for mycoViruses, have been developed for specific Viruses infecting the white root rot fungus. Using a polyethylene glycol (PEG)-mediated method, as established for MyRV1 and MyRV2 infecting C. parasitaca (27, 28), RnPV1 and MyRV3 were shown to be infectious as particles (45, 46). Subsequently, the cause-effect relationship was established: MyRV3 was demonstrated to confer hypovirulence (attenuated virulence) on an isogenic strain and a few vegetatively incompatible virulent strains of R. necatrix (33, 45), while RnPV1 was shown to be associated with symptomless infection. Protoplast fusion is also available for introduction of partitiViruses and uncharacterized Viruses into recipient fungal strains that are vegetatively incompatible with Virus-containing ones (A. Sasaki, unpublished results). Furthermore, DNA transformation systems are available for foreign gene expression in R. necatrix (33, 42). These technical advances have made the R. necatrix-mycoVirus systems attractive for studies of Virus-host interactions and virocontrol (23, 37). R. necatrix strain W779 was isolated by Ikeda et al. (29, 30) from soil in Ibaraki Prefecture as a dsRNA-positive strain that had yet to be characterized. Here we describe the purification and biological and molecular properties of a novel Virus isolated from W779. Particles ∼50 nm in diameter isolated from strain W779 consist of two dsRNA elements termed dsRNA-1 and -2 of approximately 9 and 7 kbp and a major protein of 135 kDa encoded by one of two open reading frames (ORFs) on dsRNA-1. Importantly, purified Virus particles were shown to be infectious and confer hypovirulence on vegetatively incompatible fungal strains. The two dsRNA segments share the conserved terminal sequences at both ends, and both possess extremely long (>1.6 kb) 5′ untranslated regions (UTRs) similar to each other, two ORFs, and relatively short 3′ UTRs. The 3′-proximal ORF of dsRNA-1 encodes an RNA-dependent RNA polymerase (RdRp) showing low levels (22 to 32%) of sequence identity to those of members of the families Totiviridae and Chrysoviridae. A phylogenetic analysis with RdRp sequences revealed that the W779 Virus is placed into a separate clade from the recognized Virus families. These attributes indicate that dsRNA-1 and -2 represent the genome segments of a novel bipartite Virus, designated Rosellinia necatrix megabirnaVirus 1 (RnMBV1), with virolocontrol agent potential. We propose the establishment of a new family, Megabirnaviridae, to accommodate RnMBV1 as the type species.
Satoko Kanematsu - One of the best experts on this subject based on the ideXlab platform.
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Viruses of the white root rot fungus rosellinia necatrix
Advances in Virus Research, 2013Co-Authors: Hideki Kondo, Satoko Kanematsu, Nobuhiro SuzukiAbstract:Abstract Rosellinia necatrix is a filamentous ascomycete that is pathogenic to a wide range of perennial plants worldwide. An extensive search for double-stranded RNA of a large collection of field isolates led to the detection of a variety of Viruses. Since the first identification of a reoVirus in this fungus in 2002, several novel Viruses have been molecularly characterized that include members of at least five Virus families. While some cause phenotypic alterations, many others show latent infections. Viruses attenuating the virulence of a host fungus to its plant hosts attract much attention as agents for virocontrol (biological control using Viruses) of the fungus, one of which is currently being tested in experimental fields. Like the Cryphonectria parasitica /Viruses, the R. necatrix /Viruses have emerged as an amenable system for studying Virus/host and Virus/Virus interactions. Several techniques have recently been developed that enhance the investigation of Virus Etiology, replication, and symptom induction in this mycoVirus/fungal host system.
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a novel bipartite double stranded rna mycoVirus from the white root rot fungus rosellinia necatrix molecular and biological characterization taxonomic considerations and potential for biological control
Journal of Virology, 2009Co-Authors: Sotaro Chiba, Satoko Kanematsu, Lakha Salaipeth, Atsuko Sasaki, Nobuhiro SuzukiAbstract:Viruses are found ubiquitously in major groups of filamentous fungi (40), and an increasing number of novel mycoViruses are being reported (3, 36). MycoViruses with RNA genomes are now classified into 10 families, of which four accommodate double-stranded RNA (dsRNA) Viruses and the remaining six comprise single-stranded RNA (ssRNA) Viruses (23). While many ssRNA mycoViruses, like hypoViruses and endornaViruses, do not produce particles, dsRNA Virus genomes, whether undivided (the family Totiviridae) or divided (11 or 12 segments for the family Reoviridae, 4 segments for the family Chrysoviridae, and 2 segments for the family Partitiviridae), are encapsidated in rigid particles. Most mycoViruses are considered to cause cryptic infections, while some cause phenotypic alterations that include hypovirulence and debilitation. However, the lack of artificial introduction methods for most mycoViruses has greatly hampered progress in exploring mycoVirus-host interactions (23, 40). Thus, a Virus Etiology of altered fungal phenotypes was established only for a limited number of examples, including hypoVirus-C. parasitica and mycoreoVirus-C. parasitica. White root rot is one of the most devastating diseases of perennial crops worldwide, particularly highly valued fruits in Japan like apple, Japanese pear, and grapevine. The causal fungus, Rosellinia necatrix, is an ascomycete with a wide range of host plants of >197 species spanning 50 families (31) and is difficult to control by conventional methods, as is often the case for soilborne pathogens. Fungicide application, though it may be effective, is labor-intensive and raises environmental concerns, while cultural practices may not be effective. Successful biocontrol of chestnut blight disease in Europe with hypovirulent strains (25, 38) inspired a group of Japanese researchers to conduct an extensive search of a large collection of >1,000 field fungal isolates for mycoViruses that might serve as virocontrol agents. Virocontrol or virological control refers to one form of biological control utilizing Viruses that infect organisms pathogenic to useful organisms (23). Approximately 20% of the collected isolates of R. necatrix were found to be dsRNA positive and presumed to be infected by mycoViruses (4, 29). Agarose gel profiles of dsRNAs suggested infections by members in the families Totiviridae, Partitiviridae, Reoviridae, and Chrysoviridae, as well as unassigned Viruses (S. Kanematsu and A. Sasaki, unpublished results). Among those dsRNAs, the genomic segments of MycoreoVirus 3 (MyRV3) (55) and Rosellinia necatrix partitiVirus 1 (RnPV1) (44) were well characterized. However, many other dsRNAs remain uncharacterized. Artificial virion introduction protocols, which are often unavailable for mycoViruses, have been developed for specific Viruses infecting the white root rot fungus. Using a polyethylene glycol (PEG)-mediated method, as established for MyRV1 and MyRV2 infecting C. parasitaca (27, 28), RnPV1 and MyRV3 were shown to be infectious as particles (45, 46). Subsequently, the cause-effect relationship was established: MyRV3 was demonstrated to confer hypovirulence (attenuated virulence) on an isogenic strain and a few vegetatively incompatible virulent strains of R. necatrix (33, 45), while RnPV1 was shown to be associated with symptomless infection. Protoplast fusion is also available for introduction of partitiViruses and uncharacterized Viruses into recipient fungal strains that are vegetatively incompatible with Virus-containing ones (A. Sasaki, unpublished results). Furthermore, DNA transformation systems are available for foreign gene expression in R. necatrix (33, 42). These technical advances have made the R. necatrix-mycoVirus systems attractive for studies of Virus-host interactions and virocontrol (23, 37). R. necatrix strain W779 was isolated by Ikeda et al. (29, 30) from soil in Ibaraki Prefecture as a dsRNA-positive strain that had yet to be characterized. Here we describe the purification and biological and molecular properties of a novel Virus isolated from W779. Particles ∼50 nm in diameter isolated from strain W779 consist of two dsRNA elements termed dsRNA-1 and -2 of approximately 9 and 7 kbp and a major protein of 135 kDa encoded by one of two open reading frames (ORFs) on dsRNA-1. Importantly, purified Virus particles were shown to be infectious and confer hypovirulence on vegetatively incompatible fungal strains. The two dsRNA segments share the conserved terminal sequences at both ends, and both possess extremely long (>1.6 kb) 5′ untranslated regions (UTRs) similar to each other, two ORFs, and relatively short 3′ UTRs. The 3′-proximal ORF of dsRNA-1 encodes an RNA-dependent RNA polymerase (RdRp) showing low levels (22 to 32%) of sequence identity to those of members of the families Totiviridae and Chrysoviridae. A phylogenetic analysis with RdRp sequences revealed that the W779 Virus is placed into a separate clade from the recognized Virus families. These attributes indicate that dsRNA-1 and -2 represent the genome segments of a novel bipartite Virus, designated Rosellinia necatrix megabirnaVirus 1 (RnMBV1), with virolocontrol agent potential. We propose the establishment of a new family, Megabirnaviridae, to accommodate RnMBV1 as the type species.
Riitta Turunen - One of the best experts on this subject based on the ideXlab platform.
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Atopic asthma after rhinoVirus-induced wheezing is associated with DNA methylation change in the SMAD3 gene promoter
Allergy, 2018Co-Authors: Riikka Lund, Riitta Turunen, Tytti Vuorinen, Maria Osmala, Maia Malonzo, Minna Lukkarinen, Annamari Leino, Jussi Salmi, Sanna Vuorikoski, Cezmi A. AkdisAbstract:Children with rhinoVirus-induced severe early wheezing have an increased risk of developing asthma later in life. The exact molecular mechanisms for this association are still mostly unknown. To identify potential changes in the transcriptional and epigenetic regulation in rhinoVirus-associated atopic or nonatopic asthma, we analyzed a cohort of 5-year-old children (n = 45) according to the Virus Etiology of the first severe wheezing episode at the mean age of 13 months and to 5-year asthma outcome. The development of atopic asthma in children with early rhinoVirus-induced wheezing was associated with DNA methylation changes at several genomic sites in chromosomal regions previously linked to asthma. The strongest changes in atopic asthma were detected in the promoter region of SMAD3 gene at chr 15q22.33 and introns of DDO/METTL24 genes at 6q21. These changes were validated to be present also at the average age of 8 years.
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the first wheezing episode respiratory Virus Etiology atopic characteristics and illness severity
Applied Immunohistochemistry & Molecular Morphology, 2014Co-Authors: Riitta Turunen, Annamari Koistinen, Tytti Vuorinen, Benedict Arku, Olli Ruuskanen, Maria Soderlundvenermo, Tuomas JarttiAbstract:Background Susceptibility to early rhinoVirus-induced wheezing has been recognized as an important risk factor for childhood asthma, but data on the first wheezing episode are limited. The aim of this selected population study was to investigate Virus Etiology, atopic characteristics, and illness severity, as well as their interrelation, among first-time wheezing children. Methods We studied 111 first-time wheezing children aged between 3 and 23 months (88/23 in-/outpatients). The investigated factors included atopy, food, perennial and aeroallergen sensitization, eczema, atopic eczema, elevated blood eosinophil count, and parental allergic rhinitis, asthma, and smoking. Nasopharyngeal aspirates were analyzed for adenoVirus, coronaViruses, enteroViruses, bocaVirus-1 (also serologically confirmed), influenza Viruses, metapneumoVirus, parainfluenza Viruses, rhinoVirus, and respiratory syncytial Virus using PCR methods. Results The mean age of the study patients was 12 months (standard deviation 6.0). Atopic characteristics could be found in 56%, atopic eczema in 16%, and sensitization in 23% of the cases. In all samples (100%), ≥1 Viruses were detected as follows: rhinoVirus (76%), respiratory syncytial Virus (29%), bocaVirus (18%, acute infections), and other Viruses <10% each. Virus coinfections occurred in 38% of the children. RhinoVirus infection was positively associated with age, blood eosinophil count, eczema, and duration of cough, as well as parental allergic rhinitis and smoking but negatively associated with Virus coinfection (all p < 0.05). Conclusions A respiratory Virus infection can be detected in all first-time wheezing children. RhinoVirus dominated the findings and was linked to atopic characteristics, prolonged cough, and parental smoking.
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The first wheezing episode: respiratory Virus Etiology, atopic characteristics, and illness severity.
Pediatric allergy and immunology : official publication of the European Society of Pediatric Allergy and Immunology, 2014Co-Authors: Riitta Turunen, Annamari Koistinen, Tytti Vuorinen, Benedict Arku, Maria Söderlund-venermo, Olli Ruuskanen, Tuomas JarttiAbstract:Background Susceptibility to early rhinoVirus-induced wheezing has been recognized as an important risk factor for childhood asthma, but data on the first wheezing episode are limited. The aim of this selected population study was to investigate Virus Etiology, atopic characteristics, and illness severity, as well as their interrelation, among first-time wheezing children. Methods We studied 111 first-time wheezing children aged between 3 and 23 months (88/23 in-/outpatients). The investigated factors included atopy, food, perennial and aeroallergen sensitization, eczema, atopic eczema, elevated blood eosinophil count, and parental allergic rhinitis, asthma, and smoking. Nasopharyngeal aspirates were analyzed for adenoVirus, coronaViruses, enteroViruses, bocaVirus-1 (also serologically confirmed), influenza Viruses, metapneumoVirus, parainfluenza Viruses, rhinoVirus, and respiratory syncytial Virus using PCR methods. Results The mean age of the study patients was 12 months (standard deviation 6.0). Atopic characteristics could be found in 56%, atopic eczema in 16%, and sensitization in 23% of the cases. In all samples (100%), ≥1 Viruses were detected as follows: rhinoVirus (76%), respiratory syncytial Virus (29%), bocaVirus (18%, acute infections), and other Viruses
Tuomas Jartti - One of the best experts on this subject based on the ideXlab platform.
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the first wheezing episode respiratory Virus Etiology atopic characteristics and illness severity
Applied Immunohistochemistry & Molecular Morphology, 2014Co-Authors: Riitta Turunen, Annamari Koistinen, Tytti Vuorinen, Benedict Arku, Olli Ruuskanen, Maria Soderlundvenermo, Tuomas JarttiAbstract:Background Susceptibility to early rhinoVirus-induced wheezing has been recognized as an important risk factor for childhood asthma, but data on the first wheezing episode are limited. The aim of this selected population study was to investigate Virus Etiology, atopic characteristics, and illness severity, as well as their interrelation, among first-time wheezing children. Methods We studied 111 first-time wheezing children aged between 3 and 23 months (88/23 in-/outpatients). The investigated factors included atopy, food, perennial and aeroallergen sensitization, eczema, atopic eczema, elevated blood eosinophil count, and parental allergic rhinitis, asthma, and smoking. Nasopharyngeal aspirates were analyzed for adenoVirus, coronaViruses, enteroViruses, bocaVirus-1 (also serologically confirmed), influenza Viruses, metapneumoVirus, parainfluenza Viruses, rhinoVirus, and respiratory syncytial Virus using PCR methods. Results The mean age of the study patients was 12 months (standard deviation 6.0). Atopic characteristics could be found in 56%, atopic eczema in 16%, and sensitization in 23% of the cases. In all samples (100%), ≥1 Viruses were detected as follows: rhinoVirus (76%), respiratory syncytial Virus (29%), bocaVirus (18%, acute infections), and other Viruses <10% each. Virus coinfections occurred in 38% of the children. RhinoVirus infection was positively associated with age, blood eosinophil count, eczema, and duration of cough, as well as parental allergic rhinitis and smoking but negatively associated with Virus coinfection (all p < 0.05). Conclusions A respiratory Virus infection can be detected in all first-time wheezing children. RhinoVirus dominated the findings and was linked to atopic characteristics, prolonged cough, and parental smoking.
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The first wheezing episode: respiratory Virus Etiology, atopic characteristics, and illness severity.
Pediatric allergy and immunology : official publication of the European Society of Pediatric Allergy and Immunology, 2014Co-Authors: Riitta Turunen, Annamari Koistinen, Tytti Vuorinen, Benedict Arku, Maria Söderlund-venermo, Olli Ruuskanen, Tuomas JarttiAbstract:Background Susceptibility to early rhinoVirus-induced wheezing has been recognized as an important risk factor for childhood asthma, but data on the first wheezing episode are limited. The aim of this selected population study was to investigate Virus Etiology, atopic characteristics, and illness severity, as well as their interrelation, among first-time wheezing children. Methods We studied 111 first-time wheezing children aged between 3 and 23 months (88/23 in-/outpatients). The investigated factors included atopy, food, perennial and aeroallergen sensitization, eczema, atopic eczema, elevated blood eosinophil count, and parental allergic rhinitis, asthma, and smoking. Nasopharyngeal aspirates were analyzed for adenoVirus, coronaViruses, enteroViruses, bocaVirus-1 (also serologically confirmed), influenza Viruses, metapneumoVirus, parainfluenza Viruses, rhinoVirus, and respiratory syncytial Virus using PCR methods. Results The mean age of the study patients was 12 months (standard deviation 6.0). Atopic characteristics could be found in 56%, atopic eczema in 16%, and sensitization in 23% of the cases. In all samples (100%), ≥1 Viruses were detected as follows: rhinoVirus (76%), respiratory syncytial Virus (29%), bocaVirus (18%, acute infections), and other Viruses
Hideki Kondo - One of the best experts on this subject based on the ideXlab platform.
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Viruses of the white root rot fungus rosellinia necatrix
Advances in Virus Research, 2013Co-Authors: Hideki Kondo, Satoko Kanematsu, Nobuhiro SuzukiAbstract:Abstract Rosellinia necatrix is a filamentous ascomycete that is pathogenic to a wide range of perennial plants worldwide. An extensive search for double-stranded RNA of a large collection of field isolates led to the detection of a variety of Viruses. Since the first identification of a reoVirus in this fungus in 2002, several novel Viruses have been molecularly characterized that include members of at least five Virus families. While some cause phenotypic alterations, many others show latent infections. Viruses attenuating the virulence of a host fungus to its plant hosts attract much attention as agents for virocontrol (biological control using Viruses) of the fungus, one of which is currently being tested in experimental fields. Like the Cryphonectria parasitica /Viruses, the R. necatrix /Viruses have emerged as an amenable system for studying Virus/host and Virus/Virus interactions. Several techniques have recently been developed that enhance the investigation of Virus Etiology, replication, and symptom induction in this mycoVirus/fungal host system.
