Asymmetry in Synergistic Interaction Between Wheat streak mosaic virus and Triticum mosaic virus in Wheat

Wheat streak mosaic virus (WSMV) and Triticum mosaic virus (TriMV), distinct members in the family Potyviridae, are economically important wheat-infecting viruses in the Great Plains region. Previously, we reported that coinfection of wheat by WSMV and TriMV caused disease synergism with increased concentration of both viruses. The mechanisms of synergistic interaction between WSMV and TriMV and the effects of prior infection of wheat by either of these “synergistically interacting partner” (SIP) viruses on the establishment of local and systemic infection by the other SIP virus are not known. In this study, using fluorescent protein-tagged viruses, we found that prior infection of wheat by WSMV or TriMV negatively affected the onset and size of local foci elicited by subsequent SIP virus infection compared with those in buffer-inoculated wheat. These data revealed that prior infection of wheat by an SIP virus has no measurable advantage for another SIP virus on the initiation of infection and cell-to-cell movement. In TriMV-infected wheat, WSMV exhibited accelerated long-distance movement and increased accumulation of genomic RNAs compared with those in buffer-inoculated wheat, indicating that TriMV-encoded proteins complemented WSMV for efficient systemic infection. In contrast, TriMV displayed delayed systemic infection in WSMV-infected wheat, with fewer genomic RNA copies in early stages of infection compared with those in buffer-inoculated wheat. However, during late stages of infection, TriMV accumulation in WSMV-infected wheat increased rapidly with accelerated long-distance movement compared with those in buffer-inoculated wheat. Taken together, these data suggest that interactions between synergistically interacting WSMV and TriMV are asymmetrical; thus, successful establishment of synergistic interaction between unrelated viruses will depend on the order of infection of plants by SIP viruses.

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Temperature-Dependent Wsm1 and Wsm2 Gene-Specific Blockage of Viral Long-Distance Transport Provides Resistance to Wheat streak mosaic virus and Triticum mosaic virus in Wheat

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-06-16-0110-r ◽

2016 ◽

Vol 29 (9) ◽

pp. 724-738 ◽

Cited By ~ 17

Author(s):

Satyanarayana Tatineni ◽

Everlyne N. Wosula ◽

Melissa Bartels ◽

Gary L. Hein ◽

Robert A. Graybosch

Keyword(s):

Mosaic Virus ◽

Fluorescent Protein ◽

Wheat Streak Mosaic Virus ◽

Viral Resistance ◽

Wheat Cultivars ◽

Temperature Dependent ◽

Long Distance ◽

Long Distance Transport ◽

Long Distance Movement ◽

Distance Transport

Wheat streak mosaic virus (WSMV) and Triticum mosaic virus (TriMV) are economically important viral pathogens of wheat. Wheat cvs. Mace, carrying the Wsm1 gene, is resistant to WSMV and TriMV, and Snowmass, with Wsm2, is resistant to WSMV. Viral resistance in both cultivars is temperature sensitive and is effective at 18°C or below but not at higher temperatures. The underlying mechanisms of viral resistance of Wsm1 and Wsm2, nonallelic single dominant genes, are not known. In this study, we found that fluorescent protein–tagged WSMV and TriMV elicited foci that were approximately similar in number and size at 18 and 24°C, on inoculated leaves of resistant and susceptible wheat cultivars. These data suggest that resistant wheat cultivars at 18°C facilitated efficient cell-to-cell movement. Additionally, WSMV and TriMV efficiently replicated in inoculated leaves of resistant wheat cultivars at 18°C but failed to establish systemic infection, suggesting that Wsm1- and Wsm2-mediated resistance debilitated viral long-distance transport. Furthermore, we found that neither virus was able to enter the leaf sheaths of inoculated leaves or crowns of resistant wheat cultivars at 18°C but both were able to do so at 24°C. Thus, wheat cvs. Mace and Snowmass provide resistance at the long-distance movement stage by specifically blocking virus entry into the vasculature. Taken together, these data suggest that both Wsm1 and Wsm2 genes similarly confer virus resistance by temperature-dependent impairment of viral long-distance movement.

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Maize resistance to Sugarcane mosaic virus

Plant Protection Science ◽

10.17221/10550-pps ◽

2017 ◽

Vol 38 (SI 2 - 6th Conf EFPP 2002) ◽

pp. 542-544

Author(s):

R. Pokorný ◽

M. Porubová

Keyword(s):

Mosaic Virus ◽

Systemic Infection ◽

Sugarcane Mosaic Virus ◽

Resistant Line ◽

Mechanisms Of Resistance ◽

Long Distance ◽

Maize Hybrids ◽

Resistant Lines ◽

Maize Resistance ◽

Long Distance Movement

Under greenhouse conditions 12 maize hybrids derived from crosses of four resistant lines with several lines of different level of susceptibility were evaluated for resistance to Czech isolate of Sugarcane mosaic virus (SCMV). These hybrids were not fully resistant to isolate of SCMV, but the symptoms on their newly growing leaves usually developed 1 to 3 weeks later in comparison with particular susceptible line, the course of infection was significantly slower and rate of infection lower. As for mechanisms of resistance, the presence of SCMV was detected by ELISA in inoculated leaves both of resistant and susceptible lines, but virus was detected 7 days later in resistant line. Systemic infection developed only in susceptible lines. These results indicate restriction of viral long distance movement in the resistant line.

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The Rate of Cell-to-Cell Movement in Squash of Cucumber Mosaic Virus Is Affected by Sequences of the Capsid Protein

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.1999.12.7.628 ◽

1999 ◽

Vol 12 (7) ◽

pp. 628-632 ◽

Cited By ~ 34

Author(s):

Sek-Man Wong ◽

Sharon Swee-Chin Thio ◽

Michael H. Shintaku ◽

Peter Palukaitis

Keyword(s):

Amino Acids ◽

Cucumber Mosaic Virus ◽

Mosaic Virus ◽

Capsid Protein ◽

Cell Movement ◽

Systemic Infection ◽

Long Distance ◽

Local Movement ◽

Long Distance Movement

The M strain of cucumber mosaic virus (CMV) does not infect squash plants systemically and moves very slowly in inoculated cotyledons. Systemic infection and an increase in the rate of local movement were observed when amino acids 129 or 214 of the M-CMV capsid protein (CP) were altered to those present in the Fny strain of CMV. While the opposite alterations to the CP of Fny-CMV inhibited systemic infection of squash, they did not show the same effects on the rates of both cell-to-cell and long-distance movement. However, the ability of CMV to infect squash systemically was affected by the rate of cell-to-cell movement.

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Components of Arabidopsis Defense- and Ethylene-Signaling Pathways Regulate Susceptibility to Cauliflower mosaic virus by Restricting Long-Distance Movement

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-20-6-0659 ◽

2007 ◽

Vol 20 (6) ◽

pp. 659-670 ◽

Cited By ~ 52

Author(s):

Andrew J. Love ◽

Valérie Laval ◽

Chiara Geri ◽

Janet Laird ◽

A. Deri Tomos ◽

...

Keyword(s):

Mosaic Virus ◽

Systemic Acquired Resistance ◽

Fluorescent Protein ◽

Acquired Resistance ◽

Systemic Infection ◽

Cauliflower Mosaic Virus ◽

Virus Movement ◽

Wild Type ◽

Long Distance ◽

Systemic Spread

We analyzed the susceptibility of Arabidopsis mutants with defects in salicylic acid (SA) and jasmonic acid (JA)/ethylene (ET) signaling to infection by Cauliflower mosaic virus (CaMV). Mutants cpr1-1 and cpr5-2, in which SA-dependent defense signaling is activated constitutively, were substantially more resistant than the wild type to systemic infection, implicating SA signaling in defense against CaMV. However, SA-deficient NahG, sid2-2, eds5-1, and pad4-1 did not show enhanced susceptibility. A cpr5 eds5 double mutant also was resistant, suggesting that resistance in cpr5 may function partially independently of SA. Treatment of cpr5 and cpr5 eds5, but not cpr1, with salicyl-hydroxamic acid, an inhibitor of alternative oxidase, partially restored susceptibility to wild-type levels. Mutants etr1-1, etr1-3, and ein2-1, and two mutants with lesions in ET/JA-mediated defense, eds4 and eds8, also showed reduced virus susceptibility, demonstrating that ET-dependent responses also play a role in susceptibility. We used a green fluorescent protein (GFP)-expressing CaMV recombinant to monitor virus movement. In mutants with reduced susceptibility, cpr1-1, cpr5-2, and etr1-1, CaMV-GFP formed local lesions similar to the wild type, but systemic spread was almost completely absent in cpr1 and cpr5 and was substantially reduced in etr1-1. Thus, mutations with enhanced systemic acquired resistance or compromised ET signaling show diminished long-distance virus movement.

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Acibenzolar-S-Methyl Restricts Infection of Nicotiana benthamiana by Plantago Asiatica Mosaic Virus at Two Distinct Stages

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-03-19-0087-r ◽

2019 ◽

Vol 32 (11) ◽

pp. 1475-1486 ◽

Cited By ~ 1

Author(s):

Yuki Matsuo ◽

Fawzia Novianti ◽

Miki Takehara ◽

Toshiyuki Fukuhara ◽

Tsutomu Arie ◽

...

Keyword(s):

Mosaic Virus ◽

Nicotiana Benthamiana ◽

Fluorescent Protein ◽

Potato Virus X ◽

Defense Responses ◽

Plant Viruses ◽

Long Distance ◽

Plantago Asiatica ◽

Green Fluorescent ◽

Long Distance Movement

Plant activators, including acibenzolar-S-methyl (ASM), are chemical compounds that stimulate plant defense responses to pathogens. ASM treatment inhibits infection by a variety of plant viruses, however, the mechanisms of this broad-spectrum and strong effect remain poorly understood. We employed green fluorescent protein (GFP)-expressing viruses and Nicotiana benthamiana plants to identify the infection stages that are restricted by ASM. ASM suppressed infection by three viral species, plantago asiatica mosaic virus (PlAMV), potato virus X (PVX), and turnip mosaic virus (TuMV), in inoculated cells. Furthermore, ASM delayed the long-distance movement of PlAMV and PVX, and the cell-to-cell (short range) movement of TuMV. The ASM-mediated delay of long-distance movement of PlAMV was not due to the suppression of viral accumulation in the inoculated leaves, indicating that ASM restricts PlAMV infection in at least two independent steps. We used Arabidopsis thaliana mutants to show that the ASM-mediated restriction of PlAMV infection requires the NPR1 gene but was independent of the dicer-like genes essential for RNA silencing. Furthermore, experiments using protoplasts showed that ASM treatment inhibited PlAMV replication without cell death. Our approach, using GFP-expressing viruses, will be useful for the analysis of mechanisms underlying plant activator–mediated virus restriction.

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Cauliflower Mosaic Virus Isolate NY8153 Breaks Resistance in Arabidopsis Ecotype En-2

Phytopathology ◽

10.1094/phyto.1997.87.8.792 ◽

1997 ◽

Vol 87 (8) ◽

pp. 792-798 ◽

Cited By ~ 9

Author(s):

W. Tang ◽

S. M. Leisner

Keyword(s):

Arabidopsis Thaliana ◽

Mosaic Virus ◽

Virus Isolate ◽

Systemic Infection ◽

Cauliflower Mosaic Virus ◽

Limited Extent ◽

Long Distance ◽

Mechanism Of Resistance ◽

Arabidopsis Ecotype ◽

Long Distance Movement

Arabidopsis thaliana ecotype En-2 was previously shown to be resistant to cauliflower mosaic caulimovirus (CaMV) isolate CM4-184. In this study, En-2 plants were screened with eight other isolates of CaMV to identify viruses capable of overcoming resistance and to determine if the mechanism of resistance was the same for each virus. En-2 resistance to most CaMV isolates was mediated by the same mechanism, i.e., preventing virus long-distance movement. One CaMV isolate, NY8153, was found that produced a severe systemic infection on En-2 plants. In addition, the CM1841 isolate was able to spread systemically through En-2 plants, to a limited extent, without producing visible symptoms. These data indicate that the resistance shown by En-2 plants is not an all-or-none phenomenon. En-2 plants were susceptible to turnip mosaic potyvirus, suggesting that resistance is specific to CaMV.

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Analysis of Cell-to-Cell and Long-Distance Movement of a Bean Dwarf Mosaic Geminivirus-Green Fluorescent Protein Reporter in Host and Nonhost Species: Identification of Sites of Resistance

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.1999.12.4.345 ◽

1999 ◽

Vol 12 (4) ◽

pp. 345-355 ◽

Cited By ~ 36

Author(s):

H. L. Wang ◽

M. R. Sudarshana ◽

R. L. Gilbertson ◽

W. J. Lucas

Keyword(s):

Green Fluorescent Protein ◽

Viral Infection ◽

Laser Scanning ◽

Fluorescent Protein ◽

Systemic Infection ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Long Distance ◽

Green Fluorescent ◽

Long Distance Movement

A bean dwarf mosaic geminivirus-green fluorescent protein (BDMV-GFP) reporter system was employed to analyze the viral infection process in host and nonhost species. Five classes of BDMV/host interaction were identified: (i) adapted hosts (susceptible Phaseolus vulgaris cultivars) permissive for systemic infection; (ii) adapted hosts (resistant P. vulgaris cv. Othello) displaying the development of a hypersensitive response (HR) associated with resistance to systemic infection; (iii) adapted (resistant P. vulgaris cv. Black Turtle Soup T-39) and nonadapted (Vigna unguiculata) hosts in which cell-to-cell, but not long-distance, movement was permitted; (iv) nonadapted hosts (Glycine max) in which systemic infection was coat protein-dependent; and (v) nonhosts (Cucurbita maxima, Gossypium barbadense, and Zea mays) in which the virus was confined to inoculated cells. Confocal laser scanning microscopy, fluorescence microscopy, and histochemical analyses were used to identify the cellular distribution of BDMV-GFP and the host response to viral infection. With this approach, the HR in P. vulgaris cv. Othello was visualized within cells of the epidermis, cortex, and phloem of inoculated hypocotyls. Infection studies performed with four begomoviruses and infectious BDMV/tomato mottle geminivirus pseudorecombinants revealed that the HR determinant(s) mapped to the BDMV DNA-B component.

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Genetic Variation and Possible Mechanisms Driving the Evolution of Worldwide Fig mosaic virus Isolates

Phytopathology ◽

10.1094/phyto-05-13-0145-r ◽

2014 ◽

Vol 104 (1) ◽

pp. 108-114 ◽

Cited By ~ 19

Author(s):

Jeewan Jyot Walia ◽

Anouk Willemsen ◽

Eminur Elci ◽

Kadriye Caglayan ◽

Bryce W. Falk ◽

...

Keyword(s):

Genetic Variation ◽

Mosaic Virus ◽

Rna Virus ◽

Plant Viruses ◽

Long Distance ◽

Evolutionary Mechanisms ◽

Plant Materials ◽

Genomic Rnas ◽

Fig Trees ◽

Fig Mosaic Virus

Fig mosaic virus (FMV) is a multipartite negative-sense RNA virus infecting fig trees worldwide. FMV is transmitted by vegetative propagation and grafting of plant materials, and by the eriophyid mite Aceria ficus. In this work, the genetic variation and evolutionary mechanisms shaping FMV populations were characterized. Nucleotide sequences from four genomic regions (each within the genomic RNAs 1, 2, 3, and 4) from FMV isolates from different countries were determined and analyzed. FMV genetic variation was low, as is seen for many other plant viruses. Phylogenetic analysis showed some geographically distant FMV isolates which clustered together, suggesting long-distance migration. The extent of migration was limited, although varied, between countries, such that FMV populations of different countries were genetically differentiated. Analysis using several recombination algorithms suggests that genomes of some FMV isolates originated by reassortment of genomic RNAs from different genetically similar isolates. Comparison between nonsynonymous and synonymous substitutions showed selection acting on some amino acids; however, most evolved neutrally. This and neutrality tests together with the limited gene flow suggest that genetic drift plays an important role in shaping FMV populations.

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Potyviral 6K2 Protein Long-Distance Movement and Symptom-Induction Functions Are Independent and Host-Specific

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi.2004.17.5.502 ◽

2004 ◽

Vol 17 (5) ◽

pp. 502-510 ◽

Cited By ~ 28

Author(s):

Carl Spetz ◽

Jari P. T. Valkonen

Keyword(s):

Spontaneous Mutation ◽

Systemic Infection ◽

Wild Type ◽

Virus Propagation ◽

Long Distance ◽

Potato Virus A ◽

Viral Mutant ◽

Membrane Bound ◽

Long Distance Movement

Deletion of various portions, or insertion of six histidine residues (6×His) into various positions of the membrane-bound 6K2 protein (53 amino acids) of Potato virus A (PVA, genus Potyvirus), inhibited systemic infection in Nicotiana tabacum and N. benthamiana plants. However, a spontaneous mutation (Gly2Cys) that occurred in 6K2 adjacent to the 6×His insert placed between Ser1 and Gly2 enabled systemic infection in a single N. benthamiana plant. No symptoms were observed, but virus titers were similar to the symptom-inducing wild-type (wt) PVA. N. tabacum plants were not systemically infected, albeit virus propagation was observed in inoculated protoplasts. The 6×His/Gly2Cys mutant was reconstructed in vitro and serially propagated by mechanical inoculation in N. benthamiana. Following the third passage, a novel viral mutant appeared, lacking the last four His residues of the insert, as well as the Gly2 and Thr3 of 6K2. It infected N. tabacum plants systemically, and in the systemically infected N. benthamiana leaves, vein chlorosis and mild yellowing symptoms were observed, typical of wt PVA infection. The mutant virus accumulated to titers similar to wt PVA in both hosts. These results show that the PVA 6K2 protein affects viral long-distance movement and symptom induction independently and in a host-specific manner.

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Relative Susceptibility Among Alternative Host Species Prevalent in the Great Plains to Wheat streak mosaic virus

Plant Disease ◽

10.1094/pdis-09-11-0746-re ◽

2012 ◽

Vol 96 (8) ◽

pp. 1185-1192 ◽

Cited By ~ 15

Author(s):

D. Ito ◽

Z. Miller ◽

F. Menalled ◽

M. Moffet ◽

M. Burrows

Keyword(s):

Mosaic Virus ◽

Great Plains ◽

Transmission Efficiency ◽

Wheat Streak Mosaic Virus ◽

Viral Reservoir ◽

Grass Species ◽

Mechanical Transmission ◽

Weed Species ◽

Crop Species ◽

Jointed Goatgrass

Wild grasses, crops, and grassy weeds are known to host Wheat streak mosaic virus (WSMV) and its vector, the wheat curl mite (WCM). Their relative importance as a source of WSMV was evaluated. A survey of small-grain fields throughout Montana was conducted between 2008 and 2009. Cheatgrass was the most prevalent grassy weed and the most frequent viral host, with 6% infection by WSMV in 2008 (n = 125) and 15% in 2009 (n = 358). By mechanically inoculating plants with WSMV in the greenhouse, the highest susceptibility was found in rye brome (52.1%), jointed goatgrass (80.9%), and wild oat (53.9%. Quackgrass, not previously reported as a host, was susceptible to WSMV (12.7%). Mite transmission efficiency from susceptible grass species was lower than from wheat, and grass species must be a host for both WSMV and the WCM to serve as a virus source. WCM transmission was more efficient than mechanical transmission. Overall, results indicate that grass species can serve as a viral reservoir, regional variation in a weed species' susceptibility to WSMV cannot explain geographic variation in epidemic intensity, and crop species and closely related weeds (e.g., jointed goatgrass) remain the best reservoirs for both WSMV and the WCM.

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