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Gustaaf A De Zoeten - One of the best experts on this subject based on the ideXlab platform.
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mutational evidence that the vpg is involved in the replication and not the movement of pea enation mosaic virus 1
Journal of General Virology, 2000Co-Authors: Jihad S Skaf, Marilou H Schultz, Hisae Hirata, Gustaaf A De ZoetenAbstract:Pea enation mosaic disease is caused by an obligatory association between the Enamovirus Pea enation mosaic virus-1 (PEMV-1) and the umbravirus Pea enation mosaic virus-2(PEMV-2). Encapsidated RNAs 1 and 2 are covalently linked to a 3138 Da VPg encoded by the RNA of PEMV-1. To determine the role of the VPg in the pathogenicity of PEMV (PEMV-1+PEMV-2), the infectivity of clones with mutations in key amino acids in the VPg was evaluated in protoplasts and in plants. Using quantitative, real-time RT–PCR, we concluded that the inability of certain mutants to infect plants was due to their replicative (and not their movement) incompetence. Mutant clones that produced delayed and less severe infections accumulated 10- to 100-fold less RNA-1 compared to WT-RNA-1 both in plants and in protoplasts. The RNAs of clones that produced WT-like infections accumulated to levels similar to those of WT-PEMV. Also, we demonstrate that the severity of symptoms produced by WT-PEMV is proportional to the amount of RNA-1 that accumulates in infected plants and seems to be independent of the amount of RNA-2. A dual role for the VPg in the pathogenicity of PEMV is proposed.
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mutational evidence that the vpg is involved in the replication and not the movement of pea enation mosaic virus 1
Journal of General Virology, 2000Co-Authors: Jihad S Skaf, Marilou H Schultz, Hisae Hirata, Gustaaf A De ZoetenAbstract:Pea enation mosaic disease is caused by an obligatory association between the Enamovirus Pea enation mosaic virus-1 (PEMV-1) and the umbravirus Pea enation mosaic virus-2(PEMV-2). Encapsidated RNAs 1 and 2 are covalently linked to a 3138 Da VPg encoded by the RNA of PEMV-1. To determine the role of the VPg in the pathogenicity of PEMV (PEMV-1+PEMV-2), the infectivity of clones with mutations in key amino acids in the VPg was evaluated in protoplasts and in plants. Using quantitative, real-time RT–PCR, we concluded that the inability of certain mutants to infect plants was due to their replicative (and not their movement) incompetence. Mutant clones that produced delayed and less severe infections accumulated 10- to 100-fold less RNA-1 compared to WT-RNA-1 both in plants and in protoplasts. The RNAs of clones that produced WT-like infections accumulated to levels similar to those of WT-PEMV. Also, we demonstrate that the severity of symptoms produced by WT-PEMV is proportional to the amount of RNA-1 that accumulates in infected plants and seems to be independent of the amount of RNA-2. A dual role for the VPg in the pathogenicity of PEMV is proposed.
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sequencing genomic localization and initial characterization of the vpg of pea enation mosaic Enamovirus
Journal of General Virology, 1998Co-Authors: C E Wobus, Jihad S Skaf, M H Schultz, Gustaaf A De ZoetenAbstract:The amino acid sequence of the genome-linked viral protein (VPg) of pea enation mosaic Enamovirus (PEMV) has been determined. The VPg is encoded by nt 1811-1894 within ORF1 of RNA1 downstream of the proteinase motif. Direct N terminus sequencing of intact and endoproteinase Asp-N-digested VPg combined with electrospray mass spectroscopy confirmed that the VPg is composed of 28 amino acids with a molecular mass of 3138 Da. The context of the N and C terminus residues as well as the position and size of the VPg suggest that the mature VPg may be generated via post-translational proteolytic processing of the polyprotein arrangement of membrane anchor-proteinase-VPg-polymerase encoded by ORFs 1 and 2. Computer comparisons did not reveal any significant similarity between the VPg of PEMV and any other sequences including those of the VPgs of related subgroup II luteoviruses.
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the coat protein is dispensable for the establishment of systemic infections by pea enation mosaic Enamovirus
Molecular Plant-microbe Interactions, 1997Co-Authors: Jihad S Skaf, S A Demler, D G Rucker, Christiane E Wobus, Gustaaf A De ZoetenAbstract:Deletions in the coat protein (CP) open reading frame (ORF)-3 of pea enation mosaic Enamovirus (PEMV) did not inhibit the systemic movement of PEMV. As early as 48 h postinoculation, truncated viral RNAs were detected in the roots and uninoculated leaves of infected plants. The detected concentrations of truncated RNAs varied significantly between experiments but were similar to those extracted from plants infected with wild-type (WT)-PEMV. Pea plants infected with CP-less mutants exhibited wilting and necrosis that appeared faster and were more severe than observed in infections with WT-PEMV. Moreover, the absence of the CP-ORF and its protein product did not affect the formation of either double-membrane bound vesicles or replication complexes characteristic of infections by PEMV. The potential role of these structures as the movement vehicles of the infectious entity of PEMV in plants is discussed.
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pea enation mosaic Enamovirus properties and aphid transmission
1996Co-Authors: S A Demler, Gustaaf A De Zoeten, G Adam, K. F. HarrisAbstract:Pea enation mosaic Enamovirus (PEMV) has long been recognized to have a unique combination of properties and has been assigned to a monotypic group (Harrison et al., 1971), now given the generic name Enamovirus (de Zoeten and Demler, 1995). The generic characters include a bipartite, plussense, single-stranded RNA (ssRNA) genome, both RNA species (RNA-1 and RNA-2) being needed to establish a systemic infection and each being encapsidated in separate morphologically distinct icosahedral particles. The virus is transmissible by aphids in the persistent (circulative) manner and by mechanical inoculation. Some isolates also contain a nonessential third RNA species, designated RNA-3.
Nicolás Bejerman - One of the best experts on this subject based on the ideXlab platform.
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High-Throughput Sequencing for Deciphering the Virome of Alfalfa (Medicago sativa L.).
Frontiers in Microbiology, 2020Co-Authors: Nicolás Bejerman, Philippe Roumagnac, Lev G. NemchinovAbstract:Alfalfa (Medicago sativa L.), also known as lucerne, is a major forage crop worldwide. In the United States, it has recently become the third most valuable field crop, with an estimated value of over $9.3 billion. Alfalfa is naturally infected by many different pathogens, including viruses, obligate parasites that reproduce only inside living host cells. Traditionally, viral infections of alfalfa have been considered by breeders, growers, producers and researchers to be diseases of limited importance, although they are widespread in all major cultivation areas. However, over the past few years, due to the rapid development of high-throughput sequencing (HTS), viral metagenomics, bioinformatics tools for interpreting massive amounts of HTS data and the increasing accessibility of public data repositories for transcriptomic discoveries, several emerging viruses of alfalfa with the potential to cause serious yield losses have been described. They include alfalfa leaf curl virus (family Geminiviridae), alfalfa dwarf virus (family Rhabdoviridae), alfalfa Enamovirus 1 (family Luteoviridae), alfalfa virus S (family Alphaflexiviridae) and others. These discoveries have called into question the assumed low economic impact of viral diseases in alfalfa and further suggested their possible contribution to the severity of complex infections involving multiple pathogens. In this review, we will focus on viruses of alfalfa recently described in different laboratories on the basis of the above research methodologies.
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Microbe and Virus Interactions with Plants, a section of the journal Frontiers in Microbiology High-Throughput Sequencing for Deciphering the Virome of Alfalfa (Medicago sativa L.)
Frontiers in Microbiology, 2020Co-Authors: Nicolás Bejerman, Philippe Roumagnac, Lev NemchinovAbstract:Alfalfa (Medicago sativaL.), also known as lucerne, is a major forage crop worldwide. In the United States, it has recently become the third most valuable field crop, with an estimated value of over $9.3 billion. Alfalfa is naturally infected by many different pathogens, including viruses, obligate parasites that reproduce only inside living host cells. Traditionally, viral infections of alfalfa have been considered by breeders, growers, producers and researchers to be diseases of limited importance, although they are widespread in all major cultivation areas. However, over the past few years, due to the rapid development of high-throughput sequencing (HTS), viral metagenomics, bioinformatics tools for interpreting massive amounts of HTS data and the increasing accessibility of public data repositories for transcriptomic discoveries, several emerging viruses of alfalfa with the potential to cause serious yield losses have been described. They include alfalfa leaf curl virus (familyGeminiviridae), alfalfa dwarf virus (familyRhabdoviridae), alfalfa Enamovirus 1 (familyLuteoviridae), alfalfa virus S (familyAlphaflexiviridae) and others. These discoveries have called into question the assumed low economic impact of viral diseases in alfalfa and further suggested their possible contribution to the severity of complex infections involving multiple pathogens. In this review, we will focus on viruses of alfalfa recently described in different laboratories on the basis of the above research methodologies.
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Novel bird’s-foot trefoil RNA viruses provide insights into a clade of legume-associated Enamoviruses and rhabdoviruses
Archives of Virology, 2019Co-Authors: Humberto J. Debat, Nicolás BejermanAbstract:Here, we report the identification and characterization of two novel viruses associated with bird’s-foot trefoil. Virus sequences related to those of Enamoviruses (ssRNA (+); Luteoviridae; Enamovirus ) and nucleorhabdoviruses (ssRNA (-); Rhabdoviridae; Nucleorhabdovirus ) were detected in Lotus corniculatus transcriptome data. The genome of the tentatively named “bird’s-foot trefoil-associated virus 1” (BFTV-1) is a 13,626-nt-long negative-sense ssRNA. BFTV-1 encodes six predicted gene products in the antigenome orientation in the canonical order 3′-N-P-P3-M-G-L-5′. The genome of the proposed “bird’s-foot trefoil-associated virus 2” (BFTV-2) is 5,736 nt long with a typical 5΄-PO-P1-2-IGS-P3-P5-3′ Enamovirus genome structure. Phylogenetic analysis indicated that BFTV-1 is closely related to datura yellow vein nucleorhabdovirus and that BFTV-2 clusters into a monophyletic lineage of legume-associated Enamoviruses. This subclade of highly related and co-divergent legume-associated viruses provides insights into the evolutionary history of the Enamoviruses.
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Novel bird's-foot trefoil RNA viruses provide insights into a clade of legume-associated Enamoviruses and rhabdoviruses.
Archives of Virology, 2019Co-Authors: Humberto J. Debat, Nicolás BejermanAbstract:Here, we report the identification and characterization of two novel viruses associated with bird’s-foot trefoil. Virus sequences related to those of Enamoviruses (ssRNA (+); Luteoviridae; Enamovirus) and nucleorhabdoviruses (ssRNA (-); Rhabdoviridae; Nucleorhabdovirus) were detected in Lotus corniculatus transcriptome data. The genome of the tentatively named “bird’s-foot trefoil-associated virus 1” (BFTV-1) is a 13,626-nt-long negative-sense ssRNA. BFTV-1 encodes six predicted gene products in the antigenome orientation in the canonical order 3′-N-P-P3-M-G-L-5′. The genome of the proposed “bird’s-foot trefoil-associated virus 2” (BFTV-2) is 5,736 nt long with a typical 5΄-PO-P1-2-IGS-P3-P5-3′ Enamovirus genome structure. Phylogenetic analysis indicated that BFTV-1 is closely related to datura yellow vein nucleorhabdovirus and that BFTV-2 clusters into a monophyletic lineage of legume-associated Enamoviruses. This subclade of highly related and co-divergent legume-associated viruses provides insights into the evolutionary history of the Enamoviruses.
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Identification of novel RNA viruses associated to bird’s-foot trefoil (Lotus corniculatus)
2018Co-Authors: Humberto J. Debat, Nicolás BejermanAbstract:Bird9s-foot trefoil ( Lotus corniculatus L.) is a highly nutritious forage crop, employed for livestock foraging around the world. Despite the agronomical importance of this resilient crop, the related literature is rather scarce. Here, we report the identification and characterization of two novel viruses associated with bird9s-foot trefoil. Virus sequences with affinity to Enamoviruses (ssRNA (+); Luteoviridae ; Enamovirus ) and nucleorhabdoviruses (ssRNA (-); Rhabdoviridae ; Nucleorhabdovirus ) were detected in L. corniculatus transcriptome data. The proposed bird9s-foot trefoil Enamovirus 1 (BFTEV-1) 5,736 nt virus sequence presents a typical 59-PO-P1-2-IGS-P3-P5-39; Enamovirus genome structure. The tentatively named bird9s-foot trefoil nucleorhabdovirus (BFTNRV) genome organization is characterized by 13,626 nt long negative-sense single-stranded RNA. BFTNRV presents in its antigenome orientation six predicted gene products in the canonical order 39-N-P-P3-M-G-L-59. Phylogenetic analysis suggests that BFTNRV is closely related to Datura yellow vein nucleorhabdovirus , and that BFTEV-1 clusters into a monophyletic clade of legumes-associated Enamoviruses. The bioinformatic reanalysis of SRA libraries deposited in the NCBI database constitutes an emerging approach to the discovery of novel plant viruses. The RNA viruses reported here provide a first glimpse of the virus landscape of this important crop. Future studies should assess the prevalence of BFTEV-1 and BFTNRV, and unravel whether the infection of these novel viruses is associated to specific symptoms.
H. R. Pappu - One of the best experts on this subject based on the ideXlab platform.
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development and application of elisa assays for the detection of two members of the family luteoviridae infecting legumes pea enation mosaic virus genus Enamovirus and bean leafroll virus genus luteovirus
Annals of Applied Biology, 2014Co-Authors: B. Vemulapati, K. L. Druffel, D Husebye, Sanford D Eigenbrode, H. R. PappuAbstract:An antigen-coated plate enzyme-linked immunosorbent assay (ACP-ELISA) method was developed and validated for the detection of Bean leafroll virus (BLRV) and Pea enation mosaic virus (PEMV), two of the important viral pathogens of several legume crops. The coat protein (CP) gene of each of the viruses was bacterially expressed as a fusion protein containing an N-terminal hexa-histidine tag and used as an antigen to produce antisera in rabbits. The antiserum to BLRV could detect the virus in leaf samples in up to 1:1000 dilution, and the PEMV antiserum detected the homologous virus in leaf samples of dilutions up to 1:6400. No serological cross-reactivity was observed between anti-BLRV and anti-PEMV sera. The ACP-ELISA assays were then used for estimating the prevalence of these two viruses in alfalfa, pea and vetch over a three-state area in the US Pacific Northwest over a 2-year period and virus incidence was mapped. Availability of rapid and sensitive ELISA assays facilitate virus disease mapping efforts and screening germplasm for virus resistance.
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genomic characterization of pea enation mosaic virus 2 from the pacific northwestern usa
Archives of Virology, 2011Co-Authors: B. Vemulapati, K. L. Druffel, A. Karasev, Sanford D Eigenbrode, H. R. PappuAbstract:Pea enation mosaic virus (PEMV) infects several legume crops, including chickpea (Cicer arietinum), faba bean (Vicia faba), lentil (Lens culinaris) and pea (Pisum sativum). The virus caused yield losses of food legumes in the Pacific Northwestern US during 1983, 1987 and 1990 [1]. Our recent surveys of pea and alfalfa fields in the states of Washington and Idaho, USA, have shown the prevalence of PEMV on pea. PEMV consists of a large (RNA-1 or PEMV-1) and a small (RNA-2 or PEMV-2) single-stranded positive-sense RNA, which are encapsidated separately into distinct isometric particles [2]. PEMV-2 is one of the seven distinct virus species in the genus Umbravirus. The other species of this genus are Carrot mottle virus (CMoV), Carrot mottle mimic virus (CMoMV), Groundnut rosette virus (GRV), Lettuce speckles mottle virus (LSMV), Tobacco mottle virus (TMoV) and Tobacco bushy top virus (TBTV) [3]. Members of this group lack the coat protein (CP) gene in their genomes and depend on a helper virus for survival [4]. PEMV-2 in association with PEMV-1 (genus Enamovirus), form a symbiotic bipartite virus complex referred to as PEMV. It has been suggested that RNA-1 and RNA-2 are essential for PEMV infection [4, 5]. The RNA-1 (5706 nucleotides) encodes five major ORFs (1-5) that have nucleotide and amino acid sequence similarities with subgroup II luteoviruses [5]. While PEMV-1 provides the necessary encapsidation and vector-transmission abilities for PEMV-2, the latter provides PEMV-1 with long-distance movement and mechanical transmission functions. As part of an ongoing project to determine the genetic diversity of PEMV, we recently characterized the genome of PEMV-1 from the Pacific Northwest [6]. So far, there are only two complete genomic sequences of PEMV-2 in GenBank (NC_003853 and AY714213). To better understand sequence diversity of PEMV-2, the genome structure and organization of two PEMV isolates, one from Idaho (PEMV-2-ID) and one from Washington (PEMV-2-WA), were determined in this study. The PEMV-2 genome (*4.2 kbp), like that of other umbraviruses, predominantly consists of four ORFs (1-4), which perform diverse functions [4, 7, 8]. RNA-2 lacks a polyadenylation signal at its 30 end and contains a large 50 genome-linked protein [9]. ORF-1, at the 50 end of the virus genome, initiates after a short, 20-nt non-coding region (NCR) and encodes a putative 33-kDa protein of unknown function. ORF-2 overlaps with ORF-1 at its 30 end and potentially encodes a protein of 65 kDa through a frameshift mechanism. ORF-2 contains sequence motifs characteristic of a viral RNA-dependent RNA-polymerase (RdRp). The presence of a polymerase cassette in RNA-2 also reveals its independent replicative capabilities. Also, due to the presence of an octanucleotide frameshift signal ‘‘GGATTTTT’’ immediately upstream of the stop codon of ORF-1, ORF-1, along with ORF-2, is expressed by a -1 frameshift mechanism as a minor translation product of 97 kDa [4]. ORFs 3 and 4 in the genome occur after a nonThe sequences described here were deposited in the GenBank database with the following accession numbers: JF713435 for PEMV2-WA and JF713436 for PEMV-2-ID.
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Genomic characterization of pea enation mosaic virus-2 from the Pacific Northwestern USA
Archives of Virology, 2011Co-Authors: B. Vemulapati, K. L. Druffel, A. Karasev, Sanford D Eigenbrode, H. R. PappuAbstract:Pea enation mosaic virus (PEMV) infects several legume crops, including chickpea (Cicer arietinum), faba bean (Vicia faba), lentil (Lens culinaris) and pea (Pisum sativum). The virus caused yield losses of food legumes in the Pacific Northwestern US during 1983, 1987 and 1990 [1]. Our recent surveys of pea and alfalfa fields in the states of Washington and Idaho, USA, have shown the prevalence of PEMV on pea. PEMV consists of a large (RNA-1 or PEMV-1) and a small (RNA-2 or PEMV-2) single-stranded positive-sense RNA, which are encapsidated separately into distinct isometric particles [2]. PEMV-2 is one of the seven distinct virus species in the genus Umbravirus. The other species of this genus are Carrot mottle virus (CMoV), Carrot mottle mimic virus (CMoMV), Groundnut rosette virus (GRV), Lettuce speckles mottle virus (LSMV), Tobacco mottle virus (TMoV) and Tobacco bushy top virus (TBTV) [3]. Members of this group lack the coat protein (CP) gene in their genomes and depend on a helper virus for survival [4]. PEMV-2 in association with PEMV-1 (genus Enamovirus), form a symbiotic bipartite virus complex referred to as PEMV. It has been suggested that RNA-1 and RNA-2 are essential for PEMV infection [4, 5]. The RNA-1 (5706 nucleotides) encodes five major ORFs (1-5) that have nucleotide and amino acid sequence similarities with subgroup II luteoviruses [5]. While PEMV-1 provides the necessary encapsidation and vector-transmission abilities for PEMV-2, the latter provides PEMV-1 with long-distance movement and mechanical transmission functions. As part of an ongoing project to determine the genetic diversity of PEMV, we recently characterized the genome of PEMV-1 from the Pacific Northwest [6]. So far, there are only two complete genomic sequences of PEMV-2 in GenBank (NC_003853 and AY714213). To better understand sequence diversity of PEMV-2, the genome structure and organization of two PEMV isolates, one from Idaho (PEMV-2-ID) and one from Washington (PEMV-2-WA), were determined in this study. The PEMV-2 genome (*4.2 kbp), like that of other umbraviruses, predominantly consists of four ORFs (1-4), which perform diverse functions [4, 7, 8]. RNA-2 lacks a polyadenylation signal at its 30 end and contains a large 50 genome-linked protein [9]. ORF-1, at the 50 end of the virus genome, initiates after a short, 20-nt non-coding region (NCR) and encodes a putative 33-kDa protein of unknown function. ORF-2 overlaps with ORF-1 at its 30 end and potentially encodes a protein of 65 kDa through a frameshift mechanism. ORF-2 contains sequence motifs characteristic of a viral RNA-dependent RNA-polymerase (RdRp). The presence of a polymerase cassette in RNA-2 also reveals its independent replicative capabilities. Also, due to the presence of an octanucleotide frameshift signal ‘‘GGATTTTT’’ immediately upstream of the stop codon of ORF-1, ORF-1, along with ORF-2, is expressed by a -1 frameshift mechanism as a minor translation product of 97 kDa [4]. ORFs 3 and 4 in the genome occur after a nonThe sequences described here were deposited in the GenBank database with the following accession numbers: JF713435 for PEMV2-WA and JF713436 for PEMV-2-ID.
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Molecular characterization of pea enation mosaic virus and bean leafroll virus from the Pacific Northwest, USA
Archives of Virology, 2010Co-Authors: B. Vemulapati, K. L. Druffel, S. D. Eigenbrode, A. Karasev, H. R. PappuAbstract:The family Luteoviridae consists of eight viruses assigned to three different genera, Luteovirus , Polerovirus and Enamovirus . The complete genomic sequences of pea enation mosaic virus (genus Enamovirus ) and bean leafroll virus (genus Luteovirus ) from the Pacific Northwest, USA, were determined. Annotation, sequence comparisons, and phylogenetic analysis of selected genes together with those of known polero- and Enamoviruses were conducted.
Jihad S Skaf - One of the best experts on this subject based on the ideXlab platform.
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mutational evidence that the vpg is involved in the replication and not the movement of pea enation mosaic virus 1
Journal of General Virology, 2000Co-Authors: Jihad S Skaf, Marilou H Schultz, Hisae Hirata, Gustaaf A De ZoetenAbstract:Pea enation mosaic disease is caused by an obligatory association between the Enamovirus Pea enation mosaic virus-1 (PEMV-1) and the umbravirus Pea enation mosaic virus-2(PEMV-2). Encapsidated RNAs 1 and 2 are covalently linked to a 3138 Da VPg encoded by the RNA of PEMV-1. To determine the role of the VPg in the pathogenicity of PEMV (PEMV-1+PEMV-2), the infectivity of clones with mutations in key amino acids in the VPg was evaluated in protoplasts and in plants. Using quantitative, real-time RT–PCR, we concluded that the inability of certain mutants to infect plants was due to their replicative (and not their movement) incompetence. Mutant clones that produced delayed and less severe infections accumulated 10- to 100-fold less RNA-1 compared to WT-RNA-1 both in plants and in protoplasts. The RNAs of clones that produced WT-like infections accumulated to levels similar to those of WT-PEMV. Also, we demonstrate that the severity of symptoms produced by WT-PEMV is proportional to the amount of RNA-1 that accumulates in infected plants and seems to be independent of the amount of RNA-2. A dual role for the VPg in the pathogenicity of PEMV is proposed.
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mutational evidence that the vpg is involved in the replication and not the movement of pea enation mosaic virus 1
Journal of General Virology, 2000Co-Authors: Jihad S Skaf, Marilou H Schultz, Hisae Hirata, Gustaaf A De ZoetenAbstract:Pea enation mosaic disease is caused by an obligatory association between the Enamovirus Pea enation mosaic virus-1 (PEMV-1) and the umbravirus Pea enation mosaic virus-2(PEMV-2). Encapsidated RNAs 1 and 2 are covalently linked to a 3138 Da VPg encoded by the RNA of PEMV-1. To determine the role of the VPg in the pathogenicity of PEMV (PEMV-1+PEMV-2), the infectivity of clones with mutations in key amino acids in the VPg was evaluated in protoplasts and in plants. Using quantitative, real-time RT–PCR, we concluded that the inability of certain mutants to infect plants was due to their replicative (and not their movement) incompetence. Mutant clones that produced delayed and less severe infections accumulated 10- to 100-fold less RNA-1 compared to WT-RNA-1 both in plants and in protoplasts. The RNAs of clones that produced WT-like infections accumulated to levels similar to those of WT-PEMV. Also, we demonstrate that the severity of symptoms produced by WT-PEMV is proportional to the amount of RNA-1 that accumulates in infected plants and seems to be independent of the amount of RNA-2. A dual role for the VPg in the pathogenicity of PEMV is proposed.
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sequencing genomic localization and initial characterization of the vpg of pea enation mosaic Enamovirus
Journal of General Virology, 1998Co-Authors: C E Wobus, Jihad S Skaf, M H Schultz, Gustaaf A De ZoetenAbstract:The amino acid sequence of the genome-linked viral protein (VPg) of pea enation mosaic Enamovirus (PEMV) has been determined. The VPg is encoded by nt 1811-1894 within ORF1 of RNA1 downstream of the proteinase motif. Direct N terminus sequencing of intact and endoproteinase Asp-N-digested VPg combined with electrospray mass spectroscopy confirmed that the VPg is composed of 28 amino acids with a molecular mass of 3138 Da. The context of the N and C terminus residues as well as the position and size of the VPg suggest that the mature VPg may be generated via post-translational proteolytic processing of the polyprotein arrangement of membrane anchor-proteinase-VPg-polymerase encoded by ORFs 1 and 2. Computer comparisons did not reveal any significant similarity between the VPg of PEMV and any other sequences including those of the VPgs of related subgroup II luteoviruses.
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the coat protein is dispensable for the establishment of systemic infections by pea enation mosaic Enamovirus
Molecular Plant-microbe Interactions, 1997Co-Authors: Jihad S Skaf, S A Demler, D G Rucker, Christiane E Wobus, Gustaaf A De ZoetenAbstract:Deletions in the coat protein (CP) open reading frame (ORF)-3 of pea enation mosaic Enamovirus (PEMV) did not inhibit the systemic movement of PEMV. As early as 48 h postinoculation, truncated viral RNAs were detected in the roots and uninoculated leaves of infected plants. The detected concentrations of truncated RNAs varied significantly between experiments but were similar to those extracted from plants infected with wild-type (WT)-PEMV. Pea plants infected with CP-less mutants exhibited wilting and necrosis that appeared faster and were more severe than observed in infections with WT-PEMV. Moreover, the absence of the CP-ORF and its protein product did not affect the formation of either double-membrane bound vesicles or replication complexes characteristic of infections by PEMV. The potential role of these structures as the movement vehicles of the infectious entity of PEMV in plants is discussed.
B. Vemulapati - One of the best experts on this subject based on the ideXlab platform.
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development and application of elisa assays for the detection of two members of the family luteoviridae infecting legumes pea enation mosaic virus genus Enamovirus and bean leafroll virus genus luteovirus
Annals of Applied Biology, 2014Co-Authors: B. Vemulapati, K. L. Druffel, D Husebye, Sanford D Eigenbrode, H. R. PappuAbstract:An antigen-coated plate enzyme-linked immunosorbent assay (ACP-ELISA) method was developed and validated for the detection of Bean leafroll virus (BLRV) and Pea enation mosaic virus (PEMV), two of the important viral pathogens of several legume crops. The coat protein (CP) gene of each of the viruses was bacterially expressed as a fusion protein containing an N-terminal hexa-histidine tag and used as an antigen to produce antisera in rabbits. The antiserum to BLRV could detect the virus in leaf samples in up to 1:1000 dilution, and the PEMV antiserum detected the homologous virus in leaf samples of dilutions up to 1:6400. No serological cross-reactivity was observed between anti-BLRV and anti-PEMV sera. The ACP-ELISA assays were then used for estimating the prevalence of these two viruses in alfalfa, pea and vetch over a three-state area in the US Pacific Northwest over a 2-year period and virus incidence was mapped. Availability of rapid and sensitive ELISA assays facilitate virus disease mapping efforts and screening germplasm for virus resistance.
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genomic characterization of pea enation mosaic virus 2 from the pacific northwestern usa
Archives of Virology, 2011Co-Authors: B. Vemulapati, K. L. Druffel, A. Karasev, Sanford D Eigenbrode, H. R. PappuAbstract:Pea enation mosaic virus (PEMV) infects several legume crops, including chickpea (Cicer arietinum), faba bean (Vicia faba), lentil (Lens culinaris) and pea (Pisum sativum). The virus caused yield losses of food legumes in the Pacific Northwestern US during 1983, 1987 and 1990 [1]. Our recent surveys of pea and alfalfa fields in the states of Washington and Idaho, USA, have shown the prevalence of PEMV on pea. PEMV consists of a large (RNA-1 or PEMV-1) and a small (RNA-2 or PEMV-2) single-stranded positive-sense RNA, which are encapsidated separately into distinct isometric particles [2]. PEMV-2 is one of the seven distinct virus species in the genus Umbravirus. The other species of this genus are Carrot mottle virus (CMoV), Carrot mottle mimic virus (CMoMV), Groundnut rosette virus (GRV), Lettuce speckles mottle virus (LSMV), Tobacco mottle virus (TMoV) and Tobacco bushy top virus (TBTV) [3]. Members of this group lack the coat protein (CP) gene in their genomes and depend on a helper virus for survival [4]. PEMV-2 in association with PEMV-1 (genus Enamovirus), form a symbiotic bipartite virus complex referred to as PEMV. It has been suggested that RNA-1 and RNA-2 are essential for PEMV infection [4, 5]. The RNA-1 (5706 nucleotides) encodes five major ORFs (1-5) that have nucleotide and amino acid sequence similarities with subgroup II luteoviruses [5]. While PEMV-1 provides the necessary encapsidation and vector-transmission abilities for PEMV-2, the latter provides PEMV-1 with long-distance movement and mechanical transmission functions. As part of an ongoing project to determine the genetic diversity of PEMV, we recently characterized the genome of PEMV-1 from the Pacific Northwest [6]. So far, there are only two complete genomic sequences of PEMV-2 in GenBank (NC_003853 and AY714213). To better understand sequence diversity of PEMV-2, the genome structure and organization of two PEMV isolates, one from Idaho (PEMV-2-ID) and one from Washington (PEMV-2-WA), were determined in this study. The PEMV-2 genome (*4.2 kbp), like that of other umbraviruses, predominantly consists of four ORFs (1-4), which perform diverse functions [4, 7, 8]. RNA-2 lacks a polyadenylation signal at its 30 end and contains a large 50 genome-linked protein [9]. ORF-1, at the 50 end of the virus genome, initiates after a short, 20-nt non-coding region (NCR) and encodes a putative 33-kDa protein of unknown function. ORF-2 overlaps with ORF-1 at its 30 end and potentially encodes a protein of 65 kDa through a frameshift mechanism. ORF-2 contains sequence motifs characteristic of a viral RNA-dependent RNA-polymerase (RdRp). The presence of a polymerase cassette in RNA-2 also reveals its independent replicative capabilities. Also, due to the presence of an octanucleotide frameshift signal ‘‘GGATTTTT’’ immediately upstream of the stop codon of ORF-1, ORF-1, along with ORF-2, is expressed by a -1 frameshift mechanism as a minor translation product of 97 kDa [4]. ORFs 3 and 4 in the genome occur after a nonThe sequences described here were deposited in the GenBank database with the following accession numbers: JF713435 for PEMV2-WA and JF713436 for PEMV-2-ID.
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Genomic characterization of pea enation mosaic virus-2 from the Pacific Northwestern USA
Archives of Virology, 2011Co-Authors: B. Vemulapati, K. L. Druffel, A. Karasev, Sanford D Eigenbrode, H. R. PappuAbstract:Pea enation mosaic virus (PEMV) infects several legume crops, including chickpea (Cicer arietinum), faba bean (Vicia faba), lentil (Lens culinaris) and pea (Pisum sativum). The virus caused yield losses of food legumes in the Pacific Northwestern US during 1983, 1987 and 1990 [1]. Our recent surveys of pea and alfalfa fields in the states of Washington and Idaho, USA, have shown the prevalence of PEMV on pea. PEMV consists of a large (RNA-1 or PEMV-1) and a small (RNA-2 or PEMV-2) single-stranded positive-sense RNA, which are encapsidated separately into distinct isometric particles [2]. PEMV-2 is one of the seven distinct virus species in the genus Umbravirus. The other species of this genus are Carrot mottle virus (CMoV), Carrot mottle mimic virus (CMoMV), Groundnut rosette virus (GRV), Lettuce speckles mottle virus (LSMV), Tobacco mottle virus (TMoV) and Tobacco bushy top virus (TBTV) [3]. Members of this group lack the coat protein (CP) gene in their genomes and depend on a helper virus for survival [4]. PEMV-2 in association with PEMV-1 (genus Enamovirus), form a symbiotic bipartite virus complex referred to as PEMV. It has been suggested that RNA-1 and RNA-2 are essential for PEMV infection [4, 5]. The RNA-1 (5706 nucleotides) encodes five major ORFs (1-5) that have nucleotide and amino acid sequence similarities with subgroup II luteoviruses [5]. While PEMV-1 provides the necessary encapsidation and vector-transmission abilities for PEMV-2, the latter provides PEMV-1 with long-distance movement and mechanical transmission functions. As part of an ongoing project to determine the genetic diversity of PEMV, we recently characterized the genome of PEMV-1 from the Pacific Northwest [6]. So far, there are only two complete genomic sequences of PEMV-2 in GenBank (NC_003853 and AY714213). To better understand sequence diversity of PEMV-2, the genome structure and organization of two PEMV isolates, one from Idaho (PEMV-2-ID) and one from Washington (PEMV-2-WA), were determined in this study. The PEMV-2 genome (*4.2 kbp), like that of other umbraviruses, predominantly consists of four ORFs (1-4), which perform diverse functions [4, 7, 8]. RNA-2 lacks a polyadenylation signal at its 30 end and contains a large 50 genome-linked protein [9]. ORF-1, at the 50 end of the virus genome, initiates after a short, 20-nt non-coding region (NCR) and encodes a putative 33-kDa protein of unknown function. ORF-2 overlaps with ORF-1 at its 30 end and potentially encodes a protein of 65 kDa through a frameshift mechanism. ORF-2 contains sequence motifs characteristic of a viral RNA-dependent RNA-polymerase (RdRp). The presence of a polymerase cassette in RNA-2 also reveals its independent replicative capabilities. Also, due to the presence of an octanucleotide frameshift signal ‘‘GGATTTTT’’ immediately upstream of the stop codon of ORF-1, ORF-1, along with ORF-2, is expressed by a -1 frameshift mechanism as a minor translation product of 97 kDa [4]. ORFs 3 and 4 in the genome occur after a nonThe sequences described here were deposited in the GenBank database with the following accession numbers: JF713435 for PEMV2-WA and JF713436 for PEMV-2-ID.
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Molecular characterization of pea enation mosaic virus and bean leafroll virus from the Pacific Northwest, USA
Archives of Virology, 2010Co-Authors: B. Vemulapati, K. L. Druffel, S. D. Eigenbrode, A. Karasev, H. R. PappuAbstract:The family Luteoviridae consists of eight viruses assigned to three different genera, Luteovirus , Polerovirus and Enamovirus . The complete genomic sequences of pea enation mosaic virus (genus Enamovirus ) and bean leafroll virus (genus Luteovirus ) from the Pacific Northwest, USA, were determined. Annotation, sequence comparisons, and phylogenetic analysis of selected genes together with those of known polero- and Enamoviruses were conducted.