High-throughput sequencing technologies were used to identify plant viruses in cereal samples surveyed from 2012 to 2017. Fifteen genome sequences of a tenuivirus infecting wheat, oats, and spelt in Estonia, Norway, and Sweden were identified and characterized by their distances to other tenuivirus sequences. Like most tenuiviruses, the genome of this tenuivirus contains four genomic segments. The isolates found from different countries shared at least 92% nucleotide sequence identity at the genome level. The planthopper Javesella pellucida was identified as a vector of the virus. Laboratory transmission tests using this vector indicated that wheat, oats, barley, rye, and triticale, but none of the tested pasture grass species (Alopecurus pratensis, Dactylis glomerata, Festuca rubra, Lolium multiflorum, Phleum pratense, and Poa pratensis), are susceptible. Taking into account the vector and host range data, the tenuivirus we have found most probably represents European wheat striate mosaic virus first identified about 60 years ago. Interestingly, whereas we were not able to infect any of the tested cereal species mechanically, Nicotiana benthamiana was infected via mechanical inoculation in laboratory conditions, displaying symptoms of yellow spots and vein clearing evolving into necrosis, eventually leading to plant death. Surprisingly, one of the virus genome segments (RNA2) encoding both a putative host systemic movement enhancer protein and a putative vector transmission factor was not detected in N. benthamiana after several passages even though systemic infection was observed, raising fundamental questions about the role of this segment in the systemic spread in several hosts.
- MeSH
- genom virový * genetika MeSH
- Hemiptera virologie MeSH
- jedlá semena virologie MeSH
- nemoci rostlin virologie MeSH
- rostlinné viry * genetika MeSH
- viry mozaiky * genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Norsko MeSH
- Švédsko MeSH
Many plant viruses are vectored by insects in a persistent circulative manner. The insect gut and salivary gland are important barriers limiting virus spread, but the mechanisms by which viruses are able to cross the gut escape barriers of the insect remain largely unknown. Wheat dwarf virus (WDV), transmitted by Psammotettix alienus in a persistent, circulative, and nonpropagative manner, causes the most economically important virus disease in wheat. In this study, ADP ribosylation factor 1 (ARF1) was found to interact with the coat protein of WDV in a yeast two-hybrid, pull-down assay and to colocalise with virions in the gut and salivary glands of P. alienus. When transcription of ARF1 was suppressed by RNA interference, the WDV titre decreased in the haemolymph and salivary glands, and transmission efficiency decreased, but titre in the gut did not differ from that of the control. These data suggest that ARF1 of P. alienus binds to the WDV virion and helps virus spread from gut to haemolymph. Our study provides direct experimental evidence that WDV can use the existing membrane trafficking mechanism to aid its spread within the insect vector. This first analysis of the molecular interaction between WDV and its vector P. alienus contributes to understanding the mechanisms involved in circulative transmission of the virus by the leafhopper vector.
- MeSH
- ADP-ribosylační faktor 1 genetika metabolismus MeSH
- buněčné linie MeSH
- Geminiviridae patogenita MeSH
- Hemiptera genetika metabolismus virologie MeSH
- hmyz - vektory genetika MeSH
- nemoci rostlin virologie MeSH
- RNA interference MeSH
- slinné žlázy metabolismus virologie MeSH
- střeva virologie MeSH
- techniky dvojhybridového systému MeSH
- virion metabolismus MeSH
- virové plášťové proteiny metabolismus MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
