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E Maiss - One of the best experts on this subject based on the ideXlab platform.
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fluorescent labelling reveals spatial separation of potyvirus populations in mixed infected nicotiana benthamiana plants
Journal of General Virology, 2003Co-Authors: Christof Dietrich, E MaissAbstract:The distribution of Potyviruses in mixed infected Nicotiana benthamiana plants was investigated by using green and red fluorescent proteins (GFP, DsRed). Full-length cDNA clones of Plum pox virus (PPV-NAT-AgfpS; PPV-NAT-red), Tobacco vein mottling virus (TVMV-gfp; TVMV-red) and Clover yellow vein virus (ClYVV-GFP) expressing fluorescent proteins, referred to here as labelled viruses, were used to characterize the distribution of different potyviral populations (e.g. TVMV-gfp/PPV-NAT-red), as well as populations of identical, but differently labelled Potyviruses (e.g. PPV-NAT-AgfpS/PPV-NAT-red) or in mixed infections of Potyviruses with labelled Potato virus X (PVX). Plants infected by any of the PVX/potyvirus combinations exhibited synergistic symptoms and large numbers of cells were doubly infected. In contrast, co-infections of differently labelled potyvirus populations appeared non-synergistic and remained predominantly separate in the infected plants, independent of whether different viruses or identical but differently labelled viruses were co-infecting. Contact of differently labelled virus populations that exhibited spatial separation was restricted to a small number of cells at the border of different fluorescent cell clusters.
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Ultrastructural localization of nonstructural and coat proteins of 19 Potyviruses using antisera to bacterially expressed proteins of plum pox potyvirus
Archives of virology, 1998Co-Authors: D. Riedel, D E Lesemann, E MaissAbstract:Antisera to the bacterially expressed nonstructural proteins (NSP) HC-Pro, CI, NIa, and NIb and the coat protein (CP) of plum pox potyvirus (PPV) were used for analysing the composition of virus-induced cytoplasmic and nuclear inclusions by electron microscopy. The antisera reacted with NSP and CP of PPV on immunogold-labelled ultrathin sections. Antiserum to CP reacted with virions of seven out of 18 other Potyviruses. CP was distributed throughout the cytoplasm of infected cells. Antisera to PPV NSP specifically reacted with virus-specific cytoplasmic and/or nuclear inclusions induced by 17 different Potyviruses. NSP were furthermore localized in confined cytoplasmic areas in between complex accumulations of virus-specific inclusions. Cylindrical inclusions induced by the Potyviruses were proven to consist of CI protein. Most other cytoplasmic or nuclear inclusions were shown to be composed of two or more NSP. An unexpected composition of virus-induced inclusions was observed for the crystalline nuclear inclusions of tobacco etch virus. Here, in addition to the expected presence of NIa and NIb, HC-Pro could be demonstrated. Furthermore, amorphous cytoplasmic inclusions induced by papaya ringspot virus contained the expected HC-Pro but additionally NIa, NIb and CI. Beet mosaic virus-induced nuclear inclusions (‘satellite bodies’) contained in their electron-dense matrix NIa, NIb, Hc-Pro and CI and in their lacunae CP in bundles of virion-like filaments. The results indicate that all cytoplasmic or nuclear inclusions of Potyviruses have to be regarded as deposition sites of excessively produced viral NSP.
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the complete nucleotide sequence and genome organization of the mite transmitted brome streak mosaic rymovirus in comparison with those of Potyviruses
Journal of General Virology, 1995Co-Authors: R Gotz, E MaissAbstract:A virus isolate, designated as 11-Cal, originating from southern France has been identified as an isolate of the mite-transmitted brome streak mosaic rymovirus (BrSMV) by serological and morphological properties. BrSMV is a member of the genus Rymovirus of the family Potyviridae. The complete nucleotide sequence of the RNA genome of BrSMV has been determined. The assembled RNA is 9672 nucleotides in length, excluding a 3′-terminal poly(A)sequence. The RNA contains one open reading frame (ORF) of 9282 nucleotides coding for a polyprotein of 3093 amino acids. A comparison with typical Potyviruses showed that BrSMV has a similar genome organization. The predicted cleavage sites of the polyprotein of BrSMV are similar to those of Potyviruses. Nevertheless, unusual dipeptides are proposed in two cases. Based on the proposed location of the cleavage sites nine mature proteins are predicted. Specific motifs, described for potyviral polyproteins, are almost all present in the polyprotein of BrSMV, too. However, only an incomplete zinc-finger motif is present in the potential helper component and the motif for aphid transmission in the coat protein is not found. Several alignments of amino acid sequences showed less similarity between BrSMV and Potyviruses than between different Potyviruses.
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The complete nucleotide sequence and genome organization of the mite-transmitted brome streak mosaic rymovirus in comparison with those of Potyviruses.
The Journal of general virology, 1995Co-Authors: R Gotz, E MaissAbstract:A virus isolate, designated as 11-Cal, originating from southern France has been identified as an isolate of the mite-transmitted brome streak mosaic rymovirus (BrSMV) by serological and morphological properties. BrSMV is a member of the genus Rymovirus of the family Potyviridae. The complete nucleotide sequence of the RNA genome of BrSMV has been determined. The assembled RNA is 9672 nucleotides in length, excluding a 3'-terminal poly(A)sequence. The RNA contains one open reading frame (ORF) of 9282 nucleotides coding for a polyprotein of 3093 amino acids. A comparison with typical potyvirus showed that BrSMV has a similar genome organization. The predicted cleavage sites of the polyprotein of BrSMV are similar to those of Potyviruses. Nevertheless, unusual dipeptides are proposed in two cases. Based on the proposed location of the cleavage sites nine mature proteins are predicted. Specific motifs, described for potyviral polyproteins, are almost all present in the polyprotein of BrSMV, too. However, only an incomplete zinc-finger motif is present in the potential helper component and the motif for aphid transmission in the coat protein is not found. Several alignments of amino acid sequences showed less similarity between BrSMV and Potyviruses than between different Potyviruses.
Carole Caranta - One of the best experts on this subject based on the ideXlab platform.
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Potyviruses differ in their requirement for TOR signalling.
The Journal of general virology, 2015Co-Authors: Laurence Ouibrahim, André Moretti, Marie-helene Montane, Benoît Menand, Christian Meyer, Christophe Robaglia, Ana Giner Rubio, Carole CarantaAbstract:Potyviruses are important plant pathogens that rely on many plant cellular processes for successful infection. TOR (target of rapamycin) signalling is a key eukaryotic energy-signalling pathway controlling many cellular processes such as translation and autophagy. The dependence of Potyviruses on active TOR signalling was examined. Arabidopsis lines downregulated for TOR by RNAi were challenged with the Potyviruses watermelon mosaic virus (WMV) and turnip mosaic virus (TuMV). WMV accumulation was found to be severely altered while TuMV accumulation was only slightly delayed. In another approach, using AZD-8055, an active site inhibitor of the TOR kinase, WMV infection was found to be strongly affected. Moreover, AZD-8055 application can cure WMV infection. In contrast, TuMV infection was not affected by AZD-8055. This suggests that Potyviruses have different cellular requirements for active plant TOR signalling.
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Potyviruses differ in their requirement for TOR signaling
Journal of General Virology, 2015Co-Authors: Laurence Ouibrahim, Ana Giner Rubio, André Moretti, Marie-helene Montane, Benoît Menand, Christian Meyer, Christophe Robaglia, Carole CarantaAbstract:Potyviruses are important plant pathogens that rely on many plant cellular processes for successful infection. TOR (target of rapamycin) signaling is a key eukaryotic energy signaling pathway controlling many cellular processes such as translation and autophagy. The dependence of Potyviruses for an active TOR signaling was examined. Arabidopsis lines downregulated for TOR by RNAi were challenged with Potyviruses Watermelon Mosaic (WMV) and Turnip Mosaic (TuMV). WMV accumulation was found to be severely altered while TuMV accumulation was only slightly delayed. In another approach, using AZD-8055, an active site inhibitor of the TOR kinase, WMV infection was found to be strongly affected. Moreover, AZD-8055 application can cure WMV infection. In contrast, TuMV infection was not affected by AZD-8055. This suggests that Potyviruses have different cellular requirements for an active plant TOR signaling
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Knock-down of both eIF4E1 and eIF4E2 genes confers broad-spectrum resistance against Potyviruses in tomato
PLoS ONE, 2011Co-Authors: Marianne Mazier, Maryse Nicolai, Fabrice Flamain, Verane Sarnette, Carole CarantaAbstract:Background: The eukaryotic translation initiation factor eIF4E plays a key role in plant-potyvirus interactions. eIF4E belongs to a small multigenic family and three genes, eIF4E1, eIF4E2 and eIF(iso)4E, have been identified in tomato. It has been demonstrated that eIF4E-mediated natural recessive resistances against Potyviruses result from non-synonymous mutations in an eIF4E protein, which impair its direct interaction with the potyviral protein VPg. In tomato, the role of eIF4E proteins in potyvirus resistance is still unclear because natural or induced mutations in eIF4E1 confer only a narrow resistance spectrum against Potyviruses. This contrasts with the broad spectrum resistance identified in the natural diversity of tomato. These results suggest that more than one eIF4E protein form is involved in the observed broad spectrum resistance Methodology/Principal Findings: To gain insight into the respective contribution of each eIF4E protein in tomato-potyvirus interactions, two tomato lines silenced for both eIF4E1 and eIF4E2 (RNAi-4E) and two lines silenced for eIF(iso)4E (RNAi-iso4E) were obtained and characterized. RNAi-4E lines are slightly impaired in their growth and fertility, whereas no obvious growth defects were observed in RNAi-iso4E lines. The F1 hybrid between RNAi-4E and RNAi-iso4E lines presented a pronounced semi-dwarf phenotype. Interestingly, the RNAi-4E lines silenced for both eIF4E1 and eIF4E2 showed broad spectrum resistance to Potyviruses while the RNAi-iso4E lines were fully susceptible to Potyviruses. Yeast two-hybrid interaction assays between the three eIF4E proteins and a set of viral VPgs identified two types of VPgs: those that interacted only with eIF4E1 and those that interacted with either eIF4E1 or with eIF4E2 Conclusion/Significance: These experiments provide evidence for the involvement of both eIF4E1 and eIF4E2 in broad spectrum resistance of tomato against Potyviruses and suggest a role for eIF4E2 in tomato-potyvirus interactions.
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natural variation and functional analyses provide evidence for co evolution between plant eif4e and potyviral vpg
Plant Journal, 2008Co-Authors: Carine Charron, Christophe Robaglia, Maryse Nicolai, Jeanluc Gallois, Benoit Moury, A Palloix, Carole CarantaAbstract:Amino acid substitutions in the eukaryotic translation initiation factor 4E (eIF4E) result in recessive resistance to Potyviruses in a range of plant species, including Capsicum spp. Correspondingly, amino acid changes in the central part of the viral genome-linked protein (VPg) are responsible for the potyvirus's ability to overcome eIF4E-mediated resistance. A key observation was that physical interaction between eIF4E and the VPg is required for viral infection, and eIF4E mutations that cause resistance prevent VPg binding and inhibit the viral cycle. In this study, polymorphism analysis of the pvr2-eIF4E coding sequence in a worldwide sample of 25 C. annuum accessions identified 10 allelic variants with exclusively non-synonymous variations clustered in two surface loops of eIF4E. Resistance and genetic complementation assays demonstrated that pvr2 variants, each with signature amino acid changes, corresponded to potyvirus resistance alleles. Systematic analysis of the interactions between eIF4E proteins encoded by the 10 pvr2 alleles and VPgs of virulent and avirulent potato virus Y (PVY) and tobacco etch virus (TEV) strains demonstrated that resistance phenotypes arose from disruption of the interaction between eIF4E and VPg, and that viral adaptation to eIF4E-mediated resistance resulted from restored interaction with the resistance protein. Complementation of an eIF4E knockout yeast strain by C. annuum eIF4E proteins further shows that amino acid changes did not impede essential eIF4E functions. Altogether, these results argue in favour of a co-evolutionary 'arms race' between Capsicum eIF4E and potyviral VPg. (Resume d'auteur)
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Natural variation and functional analyses provide evidence for co-evolution between plant eIF4E and potyviral VPg
Plant Journal, 2008Co-Authors: Carine Charron, Christophe Robaglia, Maryse Nicolai, Jeanluc Gallois, Benoit Moury, A Palloix, Carole CarantaAbstract:Amino acid substitutions in the eukaryotic translation initiation factor 4E (eIF4E) result in recessive resistance to Potyviruses in a range of plant species, including Capsicum spp. Correspondingly, amino acid changes in the central part of the viral genome-linked protein (VPg) are responsible for the potyvirus’s ability to overcome eIF4E-mediated resistance. A key observation was that physical interaction between eIF4E and the VPg is required for viral infection, and eIF4E mutations that cause resistance prevent VPg binding and inhibit the viral cycle. In this study, polymorphism analysis of the pvr2-eIF4E coding sequence in a worldwide sample of 25 C. annuum accessions identified 10 allelic variants with exclusively non-synonymous variations clustered in two surface loops of eIF4E. Resistance and genetic complementation assays demonstrated that pvr2 variants, each with signature amino acid changes, corresponded to potyvirus resistance alleles. Systematic analysis of the interactions between eIF4E proteins encoded by the 10 pvr2 alleles and VPgs of virulent and avirulent potato virus Y (PVY) and tobacco etch virus (TEV) strains demonstrated that resistance phenotypes arose from disruption of the interaction between eIF4E and VPg, and that viral adaptation to eIF4E-mediated resistance resulted from restored interaction with the resistance protein. Complementation of an eIF4E knockout yeast strain by C. annuum eIF4E proteins further shows that amino acid changes did not impede essential eIF4E functions. Altogether, these results argue in favour of a co-evolutionary ‘arms race’ between Capsicum eIF4E and potyviral VPg
D. D. Shukla - One of the best experts on this subject based on the ideXlab platform.
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Characterisation and epitope analysis of monoclonal antibodies to virions of clover yellow vein and Johnsongrass mosaic Potyviruses.
Archives of virology, 1993Co-Authors: D R Hewish, X W Xiao, A Mishra, K H Gough, D. D. ShuklaAbstract:Mouse monoclonal antibodies (MAbs) against the Australian B strain of clover yellow vein (ClYVV-B) and the JG strain of Johnsongrass mosaic (JGMV) Potyviruses were produced, characterised and the epitopes with which they reacted were deduced. Using intact particles of ClYVV a total of ten MAbs were obtained which reacted strongly with ClYVV-B in an enzyme-linked immunosorbent assay and Western blots. Four of these MAbs (1, 2, 4, and 13) were found to be ClYVV-specific, as they reacted with all five ClYVV strains from Australia and the U.S.A. but not with 11 strains of bean yellow mosaic (BYMV), pea mosaic (PMV), and white lupin mosaic (WLMV) viruses which, together with ClYVV, form the BYMV subgroup of potyvirses. These MAbs failed to react with eight other potyvirus species, including six which infect legumes like the viruses in the BYMV subgroup. The ClYVV MAb 10 was found to be BYMV subgroup-specific. It reacted strongly with 15 of the 16 strains of viruses in the subgroup and gave no reaction with eight other Potyviruses. The other five ClYVV MAbs reacted with varying degrees of specificity with the BYMV subgroup viruses and also with other Potyviruses. Eight of the ClYVV MAbs (1, 2, 4, 5, 13, 17, 21, and 22) reacted with the intact coat proteins only and not with the truncated (minus amino terminus) coat protein of ClYVV suggesting that the epitopes for these MAbs are located in the surface-exposed, amino-terminal region of the ClYVV coat protein. Comparison of published coat protein sequences of BYMV and ClYVV isolates indicated that the epitopes for the four ClYVV-specific MAbs may be in the amino-terminal region spanning amino acid residues 18 to 30, whereas those for the other four MAbs may be located in the first 17 amino-terminal amino acid residue region. The epitopes that reacted with BYMV subgroup-specific MAb 10 and MAb 30 which reacted with 20 of the 24 potyvirus isolates, are probably located in the core region of ClYVV coat protein as these MAbs reacted with the intact as well as truncated coat protein of ClYVV. Analysis, in Western blot immunoassay, of 17 MAbs raised against virions of JGMV revealed that only two MAbs (1-25 and 4-30) were JGMV-specific, whereas others displayed varying degrees of specificity to different Potyviruses.(ABSTRACT TRUNCATED AT 400 WORDS)
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Characterisation and epitope analysis of monoclonal antibodies to virions of clover yellow vein and Johnsongrass mosaic Potyviruses
Archives of Virology, 1993Co-Authors: D R Hewish, X W Xiao, A Mishra, K H Gough, D. D. ShuklaAbstract:Mouse monoclonal antibodies (MAbs) against the Australian B strain of clover yellow vein (C1YVV-B) and the JG strain of Johnsongrass mosaic (JGMV) Potyviruses were produced, characterised and the epitopes with which they reacted were deduced. Using intact particles of C1YVV a total of ten MAbs were obtained which reacted strongly with C1YVV-B in an enzyme-linked immunosorbent assay and Western blots. Four of these MAbs (1, 2, 4, and 13) were found to be ClYVV-specific, as they reacted with all five C1YVV strains from Australia and the U.S.A. but not with 11 strains of bean yellow mosaic (BYMV), pea mosaic (PMV), and white lupin mosaic (WLMV) viruses which, together with C1YVV, form the BYMV subgroup of Potyviruses. These MAbs failed to react with eight other potyvirus species, including six which infect legumes like the viruses in the BYMV subgroup. The C1YVV MAb 10 was found to be BYMV subgroup-specific. It reacted strongly with 15 of the 16 strains of viruses in the subgroup and gave no reaction with eight other Potyviruses. The other five C1YVV MAbs reacted with varying degrees of specificity with the BYMV subgroup viruses and also with other Potyviruses. Eight of the C1YVV MAbs (1, 2, 4, 5, 13, 17, 21, and 22) reacted with the intact coat proteins only and not with the truncated (minus amino terminus) coat protein of C1YVV suggesting that the epitopes for these MAbs are located in the surface-exposed, amino-terminal region of the C1YVV coat protein. Comparison of published coat protein sequences of BYMV and C1YVV isolates indicated that the epitopes for the four ClYVV-specific MAbs may be in the amino-terminal region spanning amino acid residues 18 to 30, whereas those for the other four MAbs may be located in the first 17 amino-terminal amino acid residue region. The epitopes that reacted with BYMV subgroup-specific MAb 10 and MAb 30 which reacted with 20 of the 24 potyvirus isolates, are probably located in the core region of C1YVV coat protein as these MAbs reacted with the intact as well as truncated coat protein of C1YVV. Analysis, in Western blot immunoassay, of 17 MAbs raised against virions of JGMV revealed that only two MAbs (1–25 and 4–30) were JGMV-specific, whereas others displayed varying degrees of specificity to different Potyviruses. When these MAbs were screened against the intact and truncated (minus 67 amino-terminal amino acid residues) coat proteins of JGMV, the two JGMV-specific MAbs reacted only with the intact coat protein, whereas the other MAbs reacted with the intact as well as with truncated coat proteins, in Western blots. These results suggest that the epitopes for the two JGMV-specific MAbs are located in the surface-exposed amino-terminal 67 amino acid residue region and those for the cross-reactive MAbs are contained in the conserved core region of the JGMV coat protein. Screening of potyvirus MAbs against intact and truncated coat proteins thus appears to be a simple procedure to select virus-specific MAbs to Potyviruses.
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sequence data as the major criterion for potyvirus classification
Archives of virology. Supplementum, 1992Co-Authors: Colin W. Ward, Neil M. Mckern, M. J. Frenkel, D. D. ShuklaAbstract:Recent knowledge of the structure of the potyvirus particle and its components appears to have resolved what was thought to be an intractable problem of plant virology. This review describes how coat-protein and gene sequence data can be used to provide an hierarchical classification of Potyviruses. This classification puts the aphid and non-aphid-transmitted Potyviruses into a single family, divides this family into four genera that correspond to the four modes of vector transmission, discriminates distinct potyvirus species from strains, and provides a basis for the formation of subgroups composed of closely related species within a genus.
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Serology of Potyviruses: current problems and some solutions.
Archives of virology. Supplementum, 1992Co-Authors: D. D. Shukla, R. Lauricella, Colin W. WardAbstract:The serological relationships among members of the family Potyviridae are extremely complex and inconsistent. Variable cross-reactivity of polyclonal antisera, unexpected paired relationships between distinct viruses, and lack of cross-reactions between some strains are the major problems associated with the serology of Potyviruses. Recent biochemical and immunochemical investigations of coat proteins have established the molecular basis for potyvirus serology and provided explanations for most of the problems with serology of Potyviruses. Information from these studies has also formed the basis for the development of several novel approaches to the accurate detection and identification of Potyviruses. However, even these novel approaches are not without drawbacks and some of them cannot be applied easily in plant virus laboratories, since they require prior sequence information and facilities for peptide synthesis. These findings suggest that serology is an imperfect criterion for the identification and classification of Potyviruses.
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Differentiation of Potyviruses and their strains by hybridization with the 3′ non-coding region of the viral genome.
Journal of virological methods, 1992Co-Authors: M. J. Frenkel, D. D. Shukla, J. Jilka, Colin W. WardAbstract:Nucleic acid hybridization with the 3' non-coding region of the potyvirus genome as the probe was shown to be a relatively simple means of distinguishing between distinct Potyviruses and their strains. Comparisons of the nucleotide sequences of potyvirus genomes (ignoring gaps) showed that the degree of identity between equivalent genes of strains was greater than 96%, while between distinct Potyviruses the identity ranged from 42% to 65%, suggesting that any extended sequence could be considered representative of the whole genome and be suitable as a diagnostic probe. The comparisons however, also revealed that some parts of the genome, but not the 3' non-coding region, had local regions of high sequence identity that could lead to cross-hybridization between distinct Potyviruses. For this reason, and because its location immediately upstream of the poly(A) tail makes it the most accessible region for the purpose of cloning and sequencing, the 3' non-coding sequence should be most suitable for use as a diagnostic probe. Successful hybridizations (using radiolabeled, polymerase chain reaction-amplified 3' non-coding sequences) have been achieved by probing recombinant clones, purified potyviral RNA, partially purified total RNA from infected plants, and a crude extract of infected plant tissue. The method has been used to support the proposals that watermelon mosaic virus 2 and soybean mosaic virus-N are both strains of the same virus, and to discriminate between several isolates previously believed to be strains of sugarcane mosaic virus. The method should have wide application as a means of differentiating distinct Potyviruses from strains.
R Gotz - One of the best experts on this subject based on the ideXlab platform.
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the complete nucleotide sequence and genome organization of the mite transmitted brome streak mosaic rymovirus in comparison with those of Potyviruses
Journal of General Virology, 1995Co-Authors: R Gotz, E MaissAbstract:A virus isolate, designated as 11-Cal, originating from southern France has been identified as an isolate of the mite-transmitted brome streak mosaic rymovirus (BrSMV) by serological and morphological properties. BrSMV is a member of the genus Rymovirus of the family Potyviridae. The complete nucleotide sequence of the RNA genome of BrSMV has been determined. The assembled RNA is 9672 nucleotides in length, excluding a 3′-terminal poly(A)sequence. The RNA contains one open reading frame (ORF) of 9282 nucleotides coding for a polyprotein of 3093 amino acids. A comparison with typical Potyviruses showed that BrSMV has a similar genome organization. The predicted cleavage sites of the polyprotein of BrSMV are similar to those of Potyviruses. Nevertheless, unusual dipeptides are proposed in two cases. Based on the proposed location of the cleavage sites nine mature proteins are predicted. Specific motifs, described for potyviral polyproteins, are almost all present in the polyprotein of BrSMV, too. However, only an incomplete zinc-finger motif is present in the potential helper component and the motif for aphid transmission in the coat protein is not found. Several alignments of amino acid sequences showed less similarity between BrSMV and Potyviruses than between different Potyviruses.
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The complete nucleotide sequence and genome organization of the mite-transmitted brome streak mosaic rymovirus in comparison with those of Potyviruses.
The Journal of general virology, 1995Co-Authors: R Gotz, E MaissAbstract:A virus isolate, designated as 11-Cal, originating from southern France has been identified as an isolate of the mite-transmitted brome streak mosaic rymovirus (BrSMV) by serological and morphological properties. BrSMV is a member of the genus Rymovirus of the family Potyviridae. The complete nucleotide sequence of the RNA genome of BrSMV has been determined. The assembled RNA is 9672 nucleotides in length, excluding a 3'-terminal poly(A)sequence. The RNA contains one open reading frame (ORF) of 9282 nucleotides coding for a polyprotein of 3093 amino acids. A comparison with typical potyvirus showed that BrSMV has a similar genome organization. The predicted cleavage sites of the polyprotein of BrSMV are similar to those of Potyviruses. Nevertheless, unusual dipeptides are proposed in two cases. Based on the proposed location of the cleavage sites nine mature proteins are predicted. Specific motifs, described for potyviral polyproteins, are almost all present in the polyprotein of BrSMV, too. However, only an incomplete zinc-finger motif is present in the potential helper component and the motif for aphid transmission in the coat protein is not found. Several alignments of amino acid sequences showed less similarity between BrSMV and Potyviruses than between different Potyviruses.
H J Vetten - One of the best experts on this subject based on the ideXlab platform.
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further evidence that shallot yellow stripe virus sysv is a distinct potyvirus and reidentification of welsh onion yellow stripe virus as a sysv strain
Phytopathology, 1999Co-Authors: R A A Van Der Vlugt, P Steffens, C Cuperus, E Barg, D E Lesemann, H J VettenAbstract:ABSTRACT An antiserum to shallot yellow stripe virus (SYSV) was raised and used in combination with a range of other antisera to Potyviruses of Allium spp. in electron microscopic decoration experiments. The serological results corroborated an earlier finding that the type isolates of SYSV and Welsh onion yellow stripe virus (WoYSV) are closely related to each other and only distantly related to onion yellow dwarf (OYDV) and leek yellow stripe (LYSV) viruses, the two other major Potyviruses infecting Allium spp. Moreover, the decoration results indicated that Japanese Potyviruses named OYDV and Wakegi yellow dwarf virus are isolates of SYSV. Sequence analysis of the 3′-terminal regions of the SYSV and WoYSV ge-nomes revealed coat protein (CP) amino acid and 3′-nontranslated region (3′-NTR) nucleotide sequence identities of 95 and 89%, respectively. The CP amino acid and 3′-NTR nucleotide sequences of these viruses differed from those of OYDV and LYSV by >25 and >67%, respectively. The serological and mole...
