Molecular characterization, ecology, and epidemiology of a novel Tymovirus in Asclepias viridis from Oklahoma.

Native virus-plant interactions require more understanding and their study will provide a basis from which to identify potential sources of emerging destructive viruses in crops. A novel tymovirus sequence was detected in Asclepias viridis (green milkweed), a perennial growing in a natural setting in the Tallgrass Prairie Preserve (TGPP) of Oklahoma. It was abundant within and frequent among A.

A host-factor interaction and localization map for a plant-adapted rhabdovirus implicates cytoplasm-tethered transcription activators in cell-to-cell movement.

To identify host factors that play critical roles in processes, including cell-to-cell movement of plant-adapted rhabdoviruses, we constructed and validated a high-resolution Nicotiana benthamiana yeast two-hybrid library. The library was screened with the putative movement protein (sc4), nucleocapsid (N), and matrix (M) proteins of Sonchus yellow net virus (SYNV). This resulted in identification of 31 potential host factors.

Genome Structure and Production of Biologically Active In Vitro Transcripts of Cucurbit-Infecting Zucchini green mottle mosaic virus.

ABSTRACT The complete nucleotide sequence of the Zucchini green mottle mosaic virus (ZGMMV), a new member of the genus Tobamovirus, has been determined. The genome of ZGMMV is 6,513 nucleotides long and contains four open reading frames coding for proteins of 131, 189, 28, and 17 kDa from the 5' to 3' end, respectively. The 5'- and 3'-non-translated regions consist of 59 and 163 residues, respectively.

Evidence for novel viruses by analysis of nucleic acids in virus-like particle fractions from Ambrosia psilostachya.

To test the hypothesis that many viruses remain to be discovered in plants, a procedure was developed to sequence nucleic acids cloned randomly from virus-like particle fractions of plant homogenates. As a test of the efficiency of the procedure we targeted Ambrosia psilostachya, western ragweed, plants growing at the Tallgrass Prairie Preserve of northeastern Oklahoma. Amplifiable nucleic acid was found in the fractions from six of twelve specimens and sequences were characterized from four of them.

Transgenic cucumbers harboring the 54-kDa putative gene of Cucumber fruit mottle mosaic tobamovirus are highly resistant to viral infection and protect non-transgenic scions from soil infection.

Cucumber fruit mottle mosaic tobamovirus (CFMMV) causes severe mosaic symptoms and yellow mottling on leaves and fruits and, occasionally, severe wilting of cucumber (Cucumis sativus L.) plants. No genetic source of resistance against this virus has been identified in cucumber.

Molecular analysis of quasispecies of Kyuri green mottle mosaic virus.

The population diversity of progeny viruses of Kyuri green mottle mosaic virus (KGMMV) in consecutive serial passages in two systemic hosts, zucchini squash and cucumber plants, established from genetically identical viral RNA, was examined in this study. An initial plant was inoculated with in vitro transcripts from a full-length cDNA clone of KGMMV. The initial viral population (passage 0) was transferred five times in parallel populations in the same hosts species for analysis of progenies of KGMMV.

Cucumber mosaic virus 2a polymerase and 3a movement proteins independently affect both virus movement and the timing of symptom development in zucchini squash.

The basis for differences in the timing of systemic symptom elicitation in zucchini squash between a pepper strain of Cucumber mosaic virus (Pf-CMV) and a cucurbit strain (Fny-CMV) was analysed. The difference in timing of appearance of systemic symptoms was shown to map to both RNA 2 and RNA 3 of Pf-CMV, with pseudorecombinant viruses containing either RNA 2 or RNA 3 from Pf-CMV showing an intermediate rate of systemic symptom development compared with those containing both or neither Pf-CMV RNAs. Symptom phenotype was shown to map to two single-nucleotide changes, both in codons for Ile at aa 267 and 168 (in Fny-CMV RNAs 2 and 3, respectively) to Thr (in Pf-CMV RNAs 2 and 3).

Plant virus cDNA chip hybridization for detection and differentiation of four cucurbit-infecting Tobamoviruses.

A plant virus cDNA chip was developed by using viral cDNA clones and microarray technology. The cDNA chip was designed for detection and differentiation of the four species of selected cucurbit-infecting tobamoviruses [target viruses: Cucumber green mottle mosaic virus (CGMMV); Cucumber fruit mottle mosaic virus (CFMMV); Kyuri green mottle mosaic virus (KGMMV); and Zucchini green mottle mosaic virus (ZGMMV)]. The chip consisted of cDNA clones of the four cucurbit-infecting tobamoviruses, two target-related tobamoviruses, and another three unrelated plant viruses.