Serological Relationships between the Nucleocapsids of Some Planthopper-Borne Rhabdoviruses of Cereals

Maize Iranian mosaic virus (MIMV) was characterized and compared with isolates of Maize mosaic virus (MMV, genus Nucleorhabdovirus, family Rhabdoviridae) in insect transmission, cytopathology and ultrastructure of infected maize cells, virion proteins and serologically. MIMV is naturally transmitted by Ribautodelphax notabilis, a delphacid planthopper, in Iran. In this study, another planthopper, Peregrinus maidis, vector of MMV, transmitted MIMV with an estimated efficiency of 0.4-1.6% following feeding on MIMVinfected maize plants and 64% following injection of MIMV into the hemolymph, suggesting that P. maidis gut tissues largely blocked MIMV transmission. MIMV and MMV-HI (Hawaii) induced similar cytopathologies in cells of infected maize leaves, with virions budding through inner nuclear and endoplasmic reticulum membranes. In thin sections, virions of MIMV were significantly shorter than those of MMV-HI. Sodium dodecyl sulphate polyacrylamide gel electrophoresis analysis of virions of MIMV, MMV-HI, MMV-CR (Costa Rica) and MMV-FL (Florida) yielded six proteins of which four were identified as the putative G, N, P and M proteins of plant rhabdoviruses. The N, P and M proteins of MIMV migrated faster in gels than those of the MMV isolates indicating a lower molecular weight, whereas the bands corresponding to the G proteins migrated similarly for both viruses. Polyclonal antibodies to MMV-HI failed to react with virions of MIMV in enzyme-linked immunosorbent assay (ELISA) and with MIMV proteins in Western blots. In contrast, these antibodies reacted strongly with MMV-HI and MMV-FL virions in ELISA and with MMV-HI, MMV-CR and MMV-FL proteins in Western blots. Further, in ELISA, polyclonal antibodies to MMV-MR (Mauritius) reacted weakly with MIMV virions but strongly with MMV-HI and MMV-FL virions. Thus, it is concluded that MIMV is a new virus of the Nucleorhabdovirus genus that may be distantly related to MMV.www.blackwell-synergy.com

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Characterization of Maize Iranian Mosaic Virus and Comparison with Hawaiian and Other Isolates of Maize Mosaic Virus (Rhabdoviridae)

Ammar¹,

Gomez‐Luengo²,

Gordon³

et al. 2005

“…2005), may have evolved from an ancestral virus of their insect vector. However, some specific differences including, wide host range of BYSMV which can infect Bromus inermis , Dactylis glomerata , Oryza sativa , Poa pratensis and Zea mays , whereas NCMV cannot (Milne and Conti 1986; Toriyama 1986), difference in virion size of 330 × 55 nm and 350 × 68 nm in BYSMV and in NCMV, respectively (Milne and Conti 1986; Toriyama 1986), and differences in serological relationship between BYSMV and NCMV (Milne et al. 1986) which support the position of BYSMV as closer related to NCMV but distinct from species in the genus Cytorhabdovirus .…”

Section: Discussionmentioning

confidence: 99%

Analysis of the Complete Nucleotide Sequence of the Polymerase Gene ofBarley Yellow Striate Mosaic Virus- Iranian Isolate

Almasi¹,

Afsharifar²,

Niazi‎³

et al. 2010

The complete nucleotide sequence of an Iranian isolate of Barley yellow striate mosaic virus (BYSMV) L gene comprising 6171 nucleotides was determined using the random polymerase chain reaction followed by filling of gaps by the use of specific primers. The deduced L protein sequence of BYSMV showed similarities with the L proteins of other plant rhabdoviruses and contained polymerase module motifs characteristic of RNA-dependent RNA polymerases of negative-strand RNA viruses. Pairwise and multiple alignments and phylogenetic analysis of BYSMV L protein revealed that it was more closely related to cytorhabdoviruses. These results revealed that, on the basis of polymerase gene, the Iranian isolate of BYSMV and Northern cereal mosaic virus (NCMV) appeared to be the most closely related plant rhabdoviruses sequenced to date. Interestingly, the amino acid sequence identity of BYSMV ⁄ NCMV (61.3%), shared more than twice the amino acid sequence identity compared with the next two most similar cytorabdoviruses, Lettuce necrotic yellows virus (28.8%) and Lettuce yellow mottle virus (28.2%). In this paper, we discuss the similarities and differences of BYSMV with other rhabdoviruses which support the classification of BYSMV as a distinct Cytorhabdovirus. This is the first report of BYSMV genome sequences.

“…et al 1981). Although the number of plant rhabdoviruses described has increased rapidly, only some of them have been transmitted experimentally by mechanical inoculation, since they all appear to be very unstable in vitro (FRANCKI 1973), and few properties other than their morphology, have been reported (FRANCKI et al 1981, MILNE et al 1986). On the other hand, two subgroups of plant rhabdoviruses have been proposed, based oti the cellular location and the protein composition of the particles.…”

Section: Discussionmentioning

confidence: 99%

Isolation and Characterization in Gynura aurantiaca of a Possible Citrus Rhabdovirus

Rodrı́guez

Díaz-Ruíz

Flores

1988

Rhabdovirus particles were detected in greenhouse‐grown Gynura aurantiaca plants during a study of citrus diseases, and some of their biological and physicochemical properties were determined. The gynura plants displayed vein clearing of young leaves as the earliest symptom and later on, an anomalous growth of some leaves. This syndrome could be easily transmitted by graft, dodder and, with more difficulty, by sap inoculation. Electron microscopy showed bacilliform virions of about 260 × 70nm, in perinuclear spaces. Purified rhabdovirus particles inoculated to healthy plants were infectious, showing that this virus was the causal agent of the gynura syndrome. An estimate of the buoyant density in sucrose of the virus gave a value of 1.17g/,cm3. Analysis of virion proteins by SDS‐PAGE revealed four major bands of relative molecular mass 81.5, 56.6, 31.6 and 24.6 x 103, suggesting that these corresponds to the G, N, M1 and M2 proteins respectively, of the subgroup B of plant rhabdoviruses. From these data we conclude that the rhabdovirus here described should be placed in the potato yellow dwarf virus subgroup of plant rhabdoviruses. The fact that a Citrus could be the original source of the virus is discussed.