The Experts below are selected from a list of 468 Experts worldwide ranked by ideXlab platform
Michael J. Adams - One of the best experts on this subject based on the ideXlab platform.
-
ICTV Virus Taxonomy Profile: Potyviridae.
The Journal of general virology, 2017Co-Authors: Stephen J. Wylie, Frank Rabenstein, Drake C Stenger, Michael J. Adams, Jan Kreuze, Celia Chalam, Juan José López-moya, Kazusato Ohshima, Shelly Praveen, Aiming WangAbstract:The Potyviridae is the largest family of RNA plant viruses, members of which have single-stranded, positive-sense RNA genomes and flexuous filamentous particles 680–900 nm long and 11–20 nm wide. There are eight genera, distinguished by the host range, genomic features and phylogeny of the member viruses. Genomes range from 8.2 to 11.3 kb, with an average size of 9.7 kb. Most genomes are monopartite but those of members of the genus Bymovirus are bipartite. Some members cause serious disease epidemics in cultivated plants. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the taxonomy of the Potyviridae, which is available at www.ictv.global/report/potyviridae.
-
Evidence that the recessive Bymovirus resistance locus rym4 in barley corresponds to the eukaryotic translation initiation factor 4E gene
Molecular plant pathology, 2005Co-Authors: Konstantin Kanyuka, Arnis Druka, David G. Caldwell, A. Tymon, Nicola Mccallum, Robbie Waugh, Michael J. AdamsAbstract:SUMMARY Recent studies have shown that resistance in several dicotyledonous plants to viruses in the genus Potyvirus is controlled by recessive alleles of the plant translation initiation factor eIF4E or eIF(iso)4E genes. Here we provide evidence that the barley rym4 gene locus, controlling immunity to viruses in the genus Bymovirus, corresponds to eIF4E. A molecular marker based on the sequence of eIF4E was developed and used to demonstrate that eIF4E and rym4 map to the same genetic interval on chromosome 3HL in barley. Another genetic marker was developed that detects a polymorphism in the coding sequence of eIF4E and consistently distinguishes between rym4 and susceptible barley cultivars of diverse parentage. The eIF4E gene product from barley genotypes carrying rym4 and allelic rym5 and rym6 genes, originating from separate exotic germplasm, and a novel resistant allele that we identified through a reverse genetics approach all contained unique amino acid substitutions compared with the wild-type protein. Three-dimensional models of the barley eIF4E protein revealed that the polymorphic residues identified are all located at or near the mRNA cap-binding pocket, similarly to recent findings from studies on recessive potyvirus resistance in dicotyledonous plants. These new data complement our earlier observations that specific mutations in Bymovirus VPg are responsible for overcoming rym4/5-controlled resistance. Because the potyviral VPg is known to interact with eIF4E in dicotyledonous plants, it appears that monocotyledonous and dicotyledonous plants have evolved a similar strategy to combat VPg-encoding viruses in the family Potyviridae.
-
codon change in the VPg coding region on
2003Co-Authors: Nongnong Shi, Gerhard Proeseler, Michael J. Adams, Konstantin KanyukaAbstract:ability of a Bymovirus to overcome the rym4
-
The complete sequence of Oat mosaic virus and evidence for deletion and duplication in RNA2.
Archives of virology, 2002Co-Authors: Tao Zheng, Jianping Chen, Jiong Chen, Michael J. AdamsAbstract:The complete nucleotide sequence of a UK isolate of oat mosaic virus (OMV) was determined. RNA1 was 7550 nt long with one large open reading frame potentially encoding a polyprotein of 262.8 kDa with features typical of Bymoviruses. RNA2 was 2284 nt in length, substantially smaller than those of other Bymoviruses sequenced. It appeared that most of the P2 region had been deleted during repeated mechanical transmission of the isolate. The 3′-UTR of RNA2 was very long (>1.25 kb) and proved to have a 532 nt slightly overlapping repeat. Phylogenetic analysis confirmed that OMV is an independent member of the genus Bymovirus.
-
The Occurrence of Barley Mild Mosaic Virus (BaMMV) in China and the Nucleotide Sequence of its Coat Protein Gene
Journal of Phytopathology, 1999Co-Authors: T. Zheng, John F. Antoniw, Y. Cheng, Jianping Chen, Michael J. AdamsAbstract:Barley mild mosaic Bymovirus (BaMMV) was detected in 1991, 1992, 1996 and 1997 by enzyme-linked immunosorbent assay and immunosorbent electron microscopy in barley (Hordeum vulgare) from three sites in China (Rudong, Yancheng and Haian). The virus was always present with barley yellow mosaic Bymovirus (BaYMV) in the Chinese BaYMV-susceptible cultivar Yanfuaizhao 3, but was not detected in 14 European and two Japanese cultivars that were tested. Electrophoresis of viral RNA and immunoblot analysis indicated that the Chinese isolate of BaMMV contained two RNAs (7.3 and 3.5 kb) and a single coat protein of approximately 33 kDa. The coat protein gene of the virus was amplified by reverse transcriptase (RT)-polymerase chain reaction (PCR), cloned into the pBluescript (13 +) vector and sequenced. It was identical in length (753 nucleotides; 251 amino acids) to that of isolates from Japan, Korea, Germany, France and the UK. Its homology with the other isolates was 87.8 to 95.2% (nucleotides) and 91.8 to 97.6% (amino acids), and the isolate was most similar to those from Korea and Japan. The results confirmed that the virus detected in China was indeed BaMMV and suggested also that a specific strain of BaMMV has long been established in China. Zusammenfassung Das barley mild mosaic Bymovirus (BaMMV) wurde 1991, 1992, 1996 und 1997 durch ELISA und ISEM in der Gerste (Hordeum vulgare) in drei Regionen Chinas (Rudong, Yancheng und Haian) nachgewiesen. Das Virus trat immer zusammen mit dem barley yellow mosaic Bymovirus (BaYMV) in der chinesichen BaYMV-anfalligen Sorte Yanfuaizhao 3 auf, jedoch nicht in den 14 europaischen und 2 japanischen Sorten, die untersucht wurden. Nach einer Elektrophorese der viralen RNA sowie einer Immunoblotanalyse konnte gezeigt werden, dai das chinesische BaMMV-Isolat zwei RNAs (7,3 und 3,5 kb) sowie ein einzelnes Hullprotein von ca, 33 kDA enthielt. Das Hullproteingen des Virus wurde durch RT-PCR amplifiziert, in dem pBluescript (13+) Vektor geklont und sequenziert. In dessen Lange (753 Nukleotide; 251 Aminosauren) ist das Gen identisch mit denen aus Isolaten aus Japan, Korea, Deutschland, Frankreich und Groibritannien. Dessen Homologie mit anderen Isolaten betrug 87,8–95,2% bei den Nukleotiden und 91,8–97,6% bei den Aminosauren, die groite Ahnlichkeit bestand mit den Isolaten aus Korea und Japan. Die Ergebnisse bestatigen die Identitat des in China entdeckten Virus als BaMMV und deuten auierdem darauf hin, dai sich ein spezifischen Stamm des BaMMV schon langer in China etabliert hat.
Yukio Shirako - One of the best experts on this subject based on the ideXlab platform.
-
barley yellow mosaic virus vpg is the determinant protein for breaking eif4e mediated recessive resistance in barley plants
Frontiers in Plant Science, 2016Co-Authors: Hideki Kondo, Thomas Kuhne, Yukio ShirakoAbstract:In this study, we investigated the barley yellow mosaic virus (BaYMV, genus Bymovirus) factor(s) responsible for breaking eIF4E-mediated recessive resistance genes (rym4/5/6) in barley. Genome mapping analysis using chimeric infectious cDNA clones between rym5-breaking (JT10) and rym5-non-breaking (JK05) isolates indicated that genome-linked viral protein (VPg) is the determinant protein for breaking the rym5 resistance. Likewise, VPg is also responsible for overcoming the resistances of rym4 and rym6 alleles. Mutational analysis identified that amino acids Ser-118, Thr-120 and His-142 in JT10 VPg are the most critical residues for overcoming rym5 resistance in protoplasts. Moreover, the rym5-non-breaking JK05 could accumulate in the rym5 protoplasts when eIF4E derived from a susceptible barley cultivar was expressed from the viral genome. Thus, the compatibility between VPg and host eIF4E determines the ability of BaYMV to infect barley plants.
-
Association of VPg and eIF4E in the host tropism at the cellular level of Barley yellow mosaic virus and Wheat yellow mosaic virus in the genus Bymovirus
Virology, 2014Co-Authors: Yukio ShirakoAbstract:Barley yellow mosaic virus (BaYMV) and Wheat yellow mosaic virus (WYMV) are separate species in the genus Bymovirus with bipartite plus-sense RNA genomes. In fields, BaYMV infects only barley and WYMV infects only wheat. Here, we studied the replicative capability of the two viruses in barley and wheat mesophyll protoplasts. BaYMV replicated in both barley and wheat protoplasts, but WYMV replicated only in wheat protoplasts. The expression of wheat translation initiation factor 4E (eIF4E), a common host factor for potyviruses, from the WYMV genome enabled WYMV replication in barley protoplasts. Replacing the BaYMV VPg gene with that of WYMV abolished BaYMV replication in barley protoplasts, whereas the additional expression of wheat eIF4E from BaYMV genome restored the replication of the BaYMV mutant in barley protoplasts. These results indicate that both VPg and the host eIF4E are involved in the host tropism of BaYMV and WYMV at the replication level.
-
Biological and genetic diversity of Wheat yellow mosaic virus (Genus Bymovirus).
Phytopathology, 2014Co-Authors: Takehiro Ohki, Yukio Shirako, Osamu Netsu, Hisayo Kojima, Jun-ichi Sakai, Masatoshi Onuki, Tetsuo Maoka, Takahide SasayaAbstract:ABSTRACT The biological and genetic diversity of Wheat yellow mosaic virus (WYMV) isolates in Japan was characterized. On the basis of wheat cultivar reactions, 14 WYMV isolates from various places were classified into pathotypes I, II, or III. These were distributed in central, northern, and southern areas of Japan, respectively. WYMV isolates comprised three genotypes (A, A′ and B) based on amino acid differences in RNA1 and two genotypes (a and b) based on amino acid differences in RNA2. A correlation was found between the WYMV RNA1-based genotype and pathotype, suggesting that factors associated with pathogenicity map to RNA1. Genotype Aa and A′a were distributed mainly in the central to southern areas of Japan, and genotype Bb was found in northern areas of Japan, as shown by reverse-transcription polymerase chain reaction restriction fragment length polymorphism analysis. Chinese isolates YA and YZ were closely related to genotypes Bb and Aa, respectively. Wheat was introduced from China to Japan in...
-
Bymovirus reverse genetics: requirements for RNA2-encoded proteins in systemic infection.
Molecular plant pathology, 2010Co-Authors: Yuan You, Yukio ShirakoAbstract:SUMMARY Barley yellow mosaic virus (BaYMV), the type species of the genus Bymovirus in the family Potyviridae in the picornavirus-like superfamily, causes a yellow mosaic disease of winter barley with significant yield losses in Europe and East Asia. Until now, infectious in vitro transcripts for the bipartite plus-sense RNA genome of any Bymovirus species have not been available, rendering molecular analyses of Bymovirus pathogenicity and the host resistance mechanisms difficult. In this study, we constructed the first cDNA clones of BaYMV RNA1 and RNA2, from which infectious RNA can be transcribed in vitro. Using in vitro transcripts, we showed that RNA1, which encodes eight proteins, including a viral proteinase NIa-Pro, the RNA-dependent RNA polymerase NIb, genome-linked viral protein VPg and the capsid protein CP, replicated autonomously in barley mesophyll protoplasts in the absence of RNA2 optimally at 15 °C, a temperature similar to the optimum for causing disease in barley fields. For systemic infection of barley plants, RNA1 alone was not sufficient and RNA2 was also required. Of the two proteins encoded on RNA2 (P1 with cysteine proteinase activity and P2 with unknown functions), P1 was essential and P2 was dispensable for systemic infectivity. The expression of both P1 and P2, but not the precursor polyprotein, together with RNA1 increased systemic infection and caused mosaic leaf symptoms. The infectious cDNA clones of BaYMV will be vital for future studies of Bymovirus–host–vector interactions at the molecular level.
R Gotz - One of the best experts on this subject based on the ideXlab platform.
-
Unterschiedliche Formen der Resistenz gegen bodenbürtige Viren des Weizens
Gesunde Pflanzen, 2007Co-Authors: Winfried Huth, R Gotz, D.-e. LesemannAbstract:In Deutschland kommen das Furovirus Soil-borne cereal mosaic virus (SBCMV) und das Bymovirus Wheat spindle streak mosaic virus (WSSMV) oft gemeinsam, vornehmlich in mehreren Roggenanbaugebieten, vor. Das Furovirus Soil-borne wheat mosaic virus (SBWMV) wurde bisher nur in einem Weizenfeld in der Nahe von Heidelberg nachgewiesen. Alle drei Viren werden durch den Pilz Polymyxa graminis ubertragen. Der Anbau resistenter Sorten ist die einzige erfolgversprechende Masnahme, um Ertragsverlusten infolge des Virusbefalles vorzubeugen.
-
Unterschiedliche Formen der Resistenz gegen bodenbürtige Viren des Weizens
Gesunde Pflanzen, 2007Co-Authors: Winfried Huth, R Gotz, D.-e. LesemannAbstract:In Deutschland kommen das Furovirus Soil-borne cereal mosaic virus (SBCMV) und das Bymovirus Wheat spindle streak mosaic virus (WSSMV) oft gemeinsam, vornehmlich in mehreren Roggenanbaugebieten, vor. Das Furovirus Soil-borne wheat mosaic virus (SBWMV) wurde bisher nur in einem Weizenfeld in der Nähe von Heidelberg nachgewiesen. Alle drei Viren werden durch den Pilz Polymyxa graminis übertragen. Der Anbau resistenter Sorten ist die einzige erfolgversprechende Maßnahme, um Ertragsverlusten infolge des Virusbefalles vorzubeugen. Die Resistenz von Weizen gegen das Bymovirus WSSMV ist mit der Immunität der Gerste gegenüber den Bymoviren Barley yellow mosaic virus und Barley mild mosaic virus vergleichbar. Im Gegensatz dazu sind alle – auch die resistenten – Weizenpflanzen potenzielle Wirte der Furoviren. Sie können nach mechanischer Inokulation mit SBWMV und SBCMV infiziert werden. Nach natürlichem Befall ist die Virusvermehrung in der Wurzel reduziert und die Viruswanderung aus der Wurzel in den Spross gehemmt. Diese Form der Resistenz wird deshalb als Translokationsresistenz bezeichnet. Die symptomfreie Entwicklung auf homogen verseuchten Feldern ist deshalb das bevorzugte Resistenzkriterium zur Selektion auf Resistenz gegenüber den bodenbürtigen Weizenviren. Die begrenzte Eignung anderer Verfahren zur Selektion resistenter Sorten wird diskutiert. In Germany the furovirus Soil-borne cereal mosaic virus (SBCMV) and the Bymovirus Wheat spindle streak mosaic virus (WSSMV) occur often together particularly in several rye production areas. Soil-borne wheat mosaic virus (SBWMV), a wheat infecting furovirus, has so far been found only in one field near Heidelberg. Each of these viruses is transmitted by Polymyxa graminis . The cultivation of resistant varieties is the only promising measure to prevent yield losses caused by soil-borne viruses. Resistance of wheat against the Bymovirus WSSMV is comparable to the immunity of barley to the Bymoviruses Barley yellow mosaic virus and Barley mild mosaic virus . In case of immunity no virus multiplication is observed in resistant cultivars. In contrast, all wheat cultivars are hosts of the furoviruses. All cultivars – including the resistant ones – can be infected following mechanical inoculation with SBWMV and SBCMV. Resistance to furoviruses is based on reduced levels of virus multiplication in roots and on inhibition of virus movement from roots to leaves. Because of the inhibited virus movement from roots to aerial parts of plants this type of resistance is referred to as translocation resistance. In spite of the different resistance mechanisms the absence of virus symptoms on the leaves is a common selection criterion for both immunity and translocation resistance. Therefore, the symptom free development of plants on uniformly infested fields is the best criterion for selecting wheat lines with resistance to soil-borne viruses. The limited suitability of other selection methods is discussed.
-
Molecular and serological relationships of Spartina mottle virus (SpMV) strains from Spartina spec. and from Cynodon dactylon to other members of the Potyviridae
Archives of Virology, 2002Co-Authors: R Gotz, W. Huth, D.-e. Lesemann, E MaissAbstract:Spartina mottle virus (SpMV) was first reported 1980 and classified by physical and biological properties as a tentative member of the genus Rymovirus in the Potyviridae . This genus was recently separated into two genera: Rymovirus and Tritimovirus . Now the sequence of the 3′-terminal part of the genome of SpMV was determined. Additionally a virus isolate originating from Cynodon dactylon in Italy was cloned and sequenced. This Assisi-isolate shared 87.5% amino acid sequence identity with SpMV. The high degree of identity and their close serological relationship indicate that SpMV and Assisi-isolate have to be regarded as different strains of one virus. The Assisi-isolate should be designated as SpMV-AV. Comparing the C-terminal part of the ORF of several Potyviridae the sequences of SpMV strains were more similar to those of the genera Rymovirus and Potyvirus than to the genera Tritimovirus , Macluravirus , Bymovirus and Ipomovirus . The comparisons revealed identities of less than 32% for the CP and 37% for the 3′-NIb/CP region, indicating that SpMV can not be classified to any of the established genera. The results of serological tests support a separate position of SpMV in the Potyviridae . We propose to introduce the name Sparmovirus for the new genus.
-
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.
-
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.
John F. Antoniw - One of the best experts on this subject based on the ideXlab platform.
-
The Occurrence of Barley Mild Mosaic Virus (BaMMV) in China and the Nucleotide Sequence of its Coat Protein Gene
Journal of Phytopathology, 1999Co-Authors: T. Zheng, John F. Antoniw, Y. Cheng, Jianping Chen, Michael J. AdamsAbstract:Barley mild mosaic Bymovirus (BaMMV) was detected in 1991, 1992, 1996 and 1997 by enzyme-linked immunosorbent assay and immunosorbent electron microscopy in barley (Hordeum vulgare) from three sites in China (Rudong, Yancheng and Haian). The virus was always present with barley yellow mosaic Bymovirus (BaYMV) in the Chinese BaYMV-susceptible cultivar Yanfuaizhao 3, but was not detected in 14 European and two Japanese cultivars that were tested. Electrophoresis of viral RNA and immunoblot analysis indicated that the Chinese isolate of BaMMV contained two RNAs (7.3 and 3.5 kb) and a single coat protein of approximately 33 kDa. The coat protein gene of the virus was amplified by reverse transcriptase (RT)-polymerase chain reaction (PCR), cloned into the pBluescript (13 +) vector and sequenced. It was identical in length (753 nucleotides; 251 amino acids) to that of isolates from Japan, Korea, Germany, France and the UK. Its homology with the other isolates was 87.8 to 95.2% (nucleotides) and 91.8 to 97.6% (amino acids), and the isolate was most similar to those from Korea and Japan. The results confirmed that the virus detected in China was indeed BaMMV and suggested also that a specific strain of BaMMV has long been established in China. Zusammenfassung Das barley mild mosaic Bymovirus (BaMMV) wurde 1991, 1992, 1996 und 1997 durch ELISA und ISEM in der Gerste (Hordeum vulgare) in drei Regionen Chinas (Rudong, Yancheng und Haian) nachgewiesen. Das Virus trat immer zusammen mit dem barley yellow mosaic Bymovirus (BaYMV) in der chinesichen BaYMV-anfalligen Sorte Yanfuaizhao 3 auf, jedoch nicht in den 14 europaischen und 2 japanischen Sorten, die untersucht wurden. Nach einer Elektrophorese der viralen RNA sowie einer Immunoblotanalyse konnte gezeigt werden, dai das chinesische BaMMV-Isolat zwei RNAs (7,3 und 3,5 kb) sowie ein einzelnes Hullprotein von ca, 33 kDA enthielt. Das Hullproteingen des Virus wurde durch RT-PCR amplifiziert, in dem pBluescript (13+) Vektor geklont und sequenziert. In dessen Lange (753 Nukleotide; 251 Aminosauren) ist das Gen identisch mit denen aus Isolaten aus Japan, Korea, Deutschland, Frankreich und Groibritannien. Dessen Homologie mit anderen Isolaten betrug 87,8–95,2% bei den Nukleotiden und 91,8–97,6% bei den Aminosauren, die groite Ahnlichkeit bestand mit den Isolaten aus Korea und Japan. Die Ergebnisse bestatigen die Identitat des in China entdeckten Virus als BaMMV und deuten auierdem darauf hin, dai sich ein spezifischen Stamm des BaMMV schon langer in China etabliert hat.
-
A large duplication in the 3′-untranslated region of a subpopulation of RNA2 of the UK-M isolate of barley mild mosaic Bymovirus
Virus research, 1997Co-Authors: Ellen Peerenboom, Volker Jacobi, Ewen J Cartwright, Hanshenning Steinbiss, Michael J. Adams, John F. AntoniwAbstract:The UK-M isolate of the bipartite barley mild mosaic Bymovirus (BaMMV UK-M) cannot be fungally transmitted, and has previously been shown to have a 1092 nt deletion in the coding region of RNA2. We now report, using sequence and reverse transcriptase-polymerase chain reaction (RT-PCR) data, that a subpopulation of BaMMV UK-M RNA2 contains a direct imperfect sequence repeat of 552 nt in the 3' untranslated region. The secondary structure of the 3' end of RNA2, and its possible effects on replication of the virus, are also discussed.
-
a large duplication in the 3 untranslated region of a subpopulation of rna2 of the uk m isolate of barley mild mosaic Bymovirus
Virus Research, 1997Co-Authors: Ellen Peerenboom, Volker Jacobi, Ewen J Cartwright, Hanshenning Steinbiss, M J Adams, John F. AntoniwAbstract:The UK-M isolate of the bipartite barley mild mosaic Bymovirus (BaMMV UK-M) cannot be fungally transmitted, and has previously been shown to have a 1092 nt deletion in the coding region of RNA2. We now report, using sequence and reverse transcriptase-polymerase chain reaction (RT-PCR) data, that a subpopulation of BaMMV UK-M RNA2 contains a direct imperfect sequence repeat of 552 nt in the 3' untranslated region. The secondary structure of the 3' end of RNA2, and its possible effects on replication of the virus, are also discussed.
-
the complete nucleotide sequence of rna 2 of a fungally transmitted uk isolate of barley mild mosaic Bymovirus and identification of amino acid combinations possibly involved in fungus transmission
Virus Research, 1996Co-Authors: Ellen Peerenboom, Volker Jacobi, John F. Antoniw, Ursula Schlichter, Ewen J Cartwright, Hanshenning Steinbiss, M J AdamsAbstract:Abstract The complete nucleotide sequence of RNA-2 of a fungally-transmitted UK isolate of barley mild mosaic Bymovirus (BaMMV isolate UK-F) was determined and compared with other published sequences, particularly UK-M, an isolate derived from the same source but which has been mechanically passaged for several years, has a deletion of about 1 kb and cannot be fungally transmitted. From an alignment of the BaMMV RNA-2 encoded protein with that for barley yellow mosaic Bymovirus (BaYMV), several regions of consistent homology were identified and extensive searches made for similarities with the proteins of other fungally-transmitted viruses, especially amongst the furovirus capsid readthrough proteins which seem especially prone to deletion and which have already been implicated in fungus transmission. The amino acid combinations ER (glutamic acid-arginine) or QR (glutamine-arginine) were found consistently in all of the viruses. They occurred in positions predicted to be on the outside of the protein, and therefore available for interaction with the fungus vector, and were also within the regions prone to spontaneous deletion. In view of the lack of other structural or sequence homologies, it is suggested that these motifs are strong candidates for involvement in fungus transmission.
-
Movement of Bymoviruses and functions of RNA2- encoded proteins of barley yellow mosaic virus
Agronomie, 1995Co-Authors: Peer M. Schenk, John F. Antoniw, Michael J. Adams, A. Sohn, J. Hamacher, Hanshenning SteinbissAbstract:Les diverses observations realisees et les donnees experimentales obtenues a partir de plantes infectees par les Bymoviruses, tel que le virus de la mosaique jaune de l'orge (BaYMV), le virus de la mosaique moderee de l'orge (BaMMV) ou le virus de la mosaique striee en fuseaux du ble (WSSMV) suggerent que leur transport a longue distance utilise les vaisseaux du phloeme. L'inoculation des racines d'orge par le BaMMV, avec des zoospores de Polymyxa graminis contamines par le virus, et l'inoculation mecanique de feuilles revelent que le transport du virus des feuilles aux racines s'effectue en moins de 5 j, tandis que le mouvement inverse est detecte 5 a 6 sem apres l'infection. Nous avons developpe un modele d'etude du transport a longue distance du Bymovirus montrant que le cycle infectieux comprend 4 etapes principales. Le transport ascendant ou descendant des Bymovirus pourrait jouer un role important pour leur replication et leur transmission. La proteine de 28 kDa du BaYMV (ARN2) pourrait intervenir dans le transport ou la replication du virus, car elle est souvent trouvee associee aux particules virales. L'ARN2 codant pour une seconde proteine de Ba YMV de 70 kDa pourrait participer a la capacite vectrice du champignon virulifere.
Gary C. Bergstrom - One of the best experts on this subject based on the ideXlab platform.
-
Assessing the resistance of winter wheat to wheat spindle streak mosaic Bymovirus
Canadian Journal of Plant Pathology, 2002Co-Authors: J. E. Carroll, Gary C. Bergstrom, Stewart M. GrayAbstract:Management of Wheat spindle streak mosaic virus (WSSMV), a Bymovirus, relies on resistant cultivars. We compared the results from mechanical inoculation with virus-infected plant sap with those of a previous study from natural infection in field trials. The six cultivars tested (Century, Wichita, TAM 200, Geneva, Harus, and Augusta) became infected via mechanical inoculation of leaves, ruling out resistance to virus replication in leaves as the basis for resistance in the cultivars considered resistant in field trials. 'Augusta' (susceptible), 'Geneva' (resistant), and germplasm KS92WGRC22 (highly resistant) were compared in field plots for numbers of symptomatic versus asymptomatic tillers. Individual plants having both infected and uninfected tillers were found only in the two resistant wheats. Resistance in 'Geneva' and KS92WGRC22 could be due to uneven movement of virus from roots into tillers or to reduced virus replication in roots. If reduced virus replication in roots is the source of resistance i...
-
Identification of RFLP markers for resistance to wheat spindle streak mosaic Bymovirus (WSSMV) disease.
Genome, 2000Co-Authors: Aftab A Khan, Gary C. Bergstrom, James C. Nelson, Mark E. SorrellsAbstract:Wheat spindle streak mosaic Bymovirus (WSSMV) causes an economically important disease of winter wheat in Europe and North America. Artificial inoculation with this virus to identify resistant wheat genotypes is difficult. This study was conducted to identify restriction fragment length polymorphism (RFLP) markers associated with resistance to this disease. A population, consisting of 104 F5 recombinant inbred lines from a cross between hexaploid Triticum aestivum cultivars 'Geneva' (resistant) and 'Augusta' (susceptible), was evaluated for WSSMV symptoms under field conditions for four years. Two linked markers on the long arm of chromosome 2D, Xbcd1095 and Xcdo373, were determined to be associated with WSSMV resistance by bulked segregant analysis of the 10 most resistant and 10 most susceptible lines. Marker Xcdo373 accounted for 79% and Xbcd1095 for 73% of the phenotypic variation. Our results suggest that resistance to WSSMV in this population is qualitative in nature and is controlled by few genes. ...
-
Dynamics of wheat spindle streak mosaic Bymovirus in winter wheat
European Journal of Plant Pathology, 1997Co-Authors: Juliet E. Carroll, Gary C. Bergstrom, Stewart M. GrayAbstract:The dynamics of wheat spindle streak mosaic Bymovirus in winter wheat were studied during two crop cycles in a field site with a history of high virus incidence. Individual plants of two susceptible cultivars were sampled from autumn to spring and the presence of virus antigen in roots and leaves was determined by ELISA. Virus incidence was higher in cv. Frankenmuth than in cv. Augusta. During year one, incidence of viral antigen in roots remained very low for four months after sowing, and did not reach maximum levels until the following spring. During year two, incidence of viral antigen in roots rose to maximum levels in autumn, only three months after sowing. These results strongly suggested that root infection occurred in spring as well as in autumn. In both cultivars and in both years, we detected the virus in roots one month prior to its detection in leaves, suggesting that virus moves slowly from roots into leaves. Maximum incidence of virus in leaves occurred in spring of both years, coinciding with the period of symptom development. Typical symptoms (yellow streaks, spindles, and mosaic) were observed in year two, whereas only mild mosaic was observed in year one. Virus antigen was detected in nonsymptomatic leaves from two months after sowing through crop senescence. Because antigen could be detected in roots throughout the crop cycle, and zoosporangia and cystosori of the fungal vector could be detected one and two months, respectively, after sowing, it is possible that wheat spindle streak mosaic Bymovirus is acquired and/or spread by the vector during the majority of the crop cycle.
-
Use of antiserum to a New York isolate of wheat spindle streak mosaic virus to detect related Bymoviruses from North America, Europe, and Asia.
Plant Disease, 1995Co-Authors: J. E. Carroll, Stewart M. Gray, Gary C. BergstromAbstract:Wheat spindle streak mosaic Bymovirus (WSSMV) is a widespread and damaging pathogen of winter wheat in North America. The diagnosis of this viral disease has relied primarily on the observation of transient symptoms that may be confused with other biotic and abiotic stresses. Virus was purified from field-infected wheat plants grown in New York and a polyclonal antiserum was produced that by enzyme-linked immunosorbent assay detected as little as 0.25 ng WSSMV/μL leaf or root sap. The antiserum reacted to Bymoviruses from North America, Europe, and Asia, including isolates of WSSMV, wheat yellow mosaic virus, and barley yellow mosaic virus, but did not detect oat mosaic virus of barley mild mosaic virus. This corroborates previous findings on serological relationships within the Bymovirus group. The antiserum did not react with other cereal viruses tested, including soilborne wheat mosaic furovirus, wheat streak mosaic rymovirus, an dbarley yellow dwarf luteovirus. The availability of this antiserum will facilitate detection of Bymoviruses and enhance research on biology, epidemiology, and management of the diseases caused by these fungal-vectored viruses
