Genome organization of plant-adpated negative-strand RNA viruses.

Colors represent proteins of similar function. Each open reading-frame is flanked by a conserved gene junction (black circle). Gene junctions lacking transcription start sites are located between the polymerase gene and trailer RNA regions. Note: “Y” is a standardized notation used here to denote movement proteins. (A) PYDV. Type species of the genus Nucleorhabdovirus. (B) CoRSV. Genus Dichorhavirus, which have bipartite genomes. Beneath the genome maps are overlays of single-plane confocal micrographs of virus-infected nuclei in leaf epidermal cells of transgenic N. benthamiana plants expressing GFP targeted to endomembranes (green). Nuclei were stained with DAPI to visualize chromatin (blue). (C) Mock. shown on left of virus-infected nuclei. Nuclei in virus-free cells have a clearly defined nuclear envelopes, with nuclei being approximately 10 μm at midsection. Scale is 5 μm. (D) CoRSV. Nuclei in these cells contain large viroplasms that exclude DAPI staining. However, the nuclear envelope is largely intact. Note that virus-infected nuclei are larger than virus-free nuclei. CoRSV, coffee ringspot virus; DAPI, 4′,6-diamidino-2-phenylindole; GFP, green fluorescent protein; ldr, leader; ORF, open reading frame; PYDV, potato yellow dwarf virus; trl, trailer.