title: The genome organization and affinities of an Australian isolate of carrot mottle umbravirus.
abstract: The genomic sequence of an Australian isolate of carrot mottle umbravirus (CMoV-A) was determined from cDNA generated from dsRNA. This provides the first data on the genome organization and phylogeny of an umbravirus. The 4201-nucleotide genome contains four major open reading frames (ORFs). Analysis suggests that ORF2 encodes an RNA-dependent RNA polymerase, that ORF4 encodes a movement protein, and that the virus has no coat protein gene. The functions of ORFs 1 and 3 remain unknown. ORF2 is probably translated following ribosomal frameshifting. ORFs 3 and 4 are probably translated from a subgenomic mRNA. Sequence comparisons showed CMoV-A to be closely related to pea enation mosaic RNA2 (PEMV-RNA2), but also to have affinities with the Bromoviridae. These findings shed light on the relationships between the luteoviruses, PEMV, and the umbraviruses and on the relationships between the carmo-like viruses and the Bromoviridae.
authors.affiliation: Natural Environment Research Council, Institute of Virology and Environmental Microbiology, Oxford, United Kingdom. mgibbs@pi.csiro.au
authors.forename: M J
authors.initials: MJ
authors.lastname: Gibbs
authors.forename: J I
authors.initials: JI
authors.lastname: Cooper
authors.forename: P M
authors.initials: PM
authors.lastname: Waterhouse
mesh_terms: D001315:Australia; D001483:Base Sequence; D018387:Codon, Initiator; D018552:Daucus carota / Q000821:virology; D016679:Genome, Viral; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D016366:Open Reading Frames; D010942:Plant Viruses / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity; D012328:RNA Viruses / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics
chemical_list: D018387:Codon, Initiator; D012367:RNA, Viral