title: Genome analysis of a severe and a mild isolate of Papaya ringspot virus-type W found in Brazil.
abstract: Papaya ringspot virus-type W (PRSV-W) is one of the most economically threatening viruses of cucurbits in Brazil. Premunization is one of the most effective PRSV control measures currently applied in squash and zucchini crops. PRSV-W-1, a mild and premunizing strain of PRSV has been successfully used to protect cucurbits against both the severe PRSV-W-C strain and other Brazilian PRSVs. To aid in understanding the mechanism by which PRSV-W-1 premunization operates, the complete genome sequences of PRSV-W-1 and PRSV-W-C were determined. PRSV-W-1 had a genome size of 10,332 nucleotides, whereas indels within the coat protein encoding gene meant that the genome size of PRSV-W-C was six nucleotides shorter than that of the mild strain. The genomes of the two strains shared 94.63% nucleotide sequence identity, with the 5' UTR and P1 being the most variable regions, and the coat protein and 3' UTR being the most conserved. Rigorous recombination analysis revealed that neither PRSV-W-1 nor PRSV-W-C was obviously recombinant, there was significant evidence that many other fully sequenced PRSV genomes were recombinant.
authors.affiliation: Embrapa Vegetables, Brasilia, DF, Brazil. alicenag@cnph.embrapa.br
authors.forename: Alice Kazuko
authors.initials: AK
authors.lastname: Inoue-Nagata
authors.forename: Carolina de Mello
authors.initials: Cde M
authors.lastname: Franco
authors.forename: Darren Patrick
authors.initials: DP
authors.lastname: Martin
authors.forename: Jorge Alberto Marques
authors.initials: JA
authors.lastname: Rezende
authors.forename: Gleydson Barros
authors.initials: GB
authors.lastname: Ferreira
authors.forename: Luisa Silva
authors.initials: LS
authors.lastname: Dutra
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Nagata
mesh_terms: D001938:Brazil; D029441:Carica / Q000821:virology*; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D016679:Genome, Viral; D010802:Phylogeny; D017800:Potyvirus / Q000145:classification / Q000235:genetics*; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA