title: Sequence variability, recombination analysis, and specific detection of the W strain of Plum pox virus.
abstract: Plum pox virus (PPV), a member of the genus Potyvirus, is the causal agent of Sharka, the most detrimental disease of stone-fruit trees worldwide. PPV isolates are grouped into seven distinct strains. The minor PPV-W strain was established recently for the divergent W3174 isolate found in Canada. Here, the partial or complete genomic sequences of four PPV-W isolates from Latvia have been determined. The completely sequenced isolates LV-141pl and LV-145bt share 93.1 and 92.1% nucleotide identity, respectively, with isolate W3174, with two regions of higher (>20%) divergence in the P1/HC-Pro and NIa (VPg) regions. Further analyses demonstrated that these two regions correspond to two independent recombination events in the W3174 genome, one involving PPV-M (approximate genome positions 692 to 1424) and the other PPV-D (nucleotides 5672 to 5789). The LV-141pl and LV-145bt isolates appear to be representatives of the "ancestral" PPV-W strain, not affected by recombination. The PPV-W intrastrain variability is substantially higher than that of all other PPV strains, with potential implications for the serological detection of PPV-W isolates. A PPV-W-specific primer pair has been developed, allowing the specific reverse-transcription polymerase chain reaction detection of all five presently available W isolates. The characterization of these new PPV-W isolates sheds light on PPV-W evolutionary history, further supports the hypothesis of its East-European origin, and opens the way for the biological and epidemiological characterization of this poorly known PPV strain.
authors.affiliation: Institute of Virology, Department of Plant Virology, Slovak Academy of Sciences, Bratislava, Slovakia. Miroslav.Glasa@savba.sk
authors.forename: Miroslav
authors.initials: M
authors.lastname: Glasa
authors.forename: Tadeusz
authors.initials: T
authors.lastname: Malinowski
authors.forename: Lukáš
authors.initials: L
authors.lastname: Predajňa
authors.forename: Neda
authors.initials: N
authors.lastname: Pupola
authors.forename: Dzintra
authors.initials: D
authors.lastname: Dekena
authors.forename: Lech
authors.initials: L
authors.lastname: Michalczuk
authors.forename: Thierry
authors.initials: T
authors.lastname: Candresse
mesh_terms: D000595:Amino Acid Sequence; D005075:Biological Evolution; D015967:Gene Expression Regulation, Viral; D014644:Genetic Variation; D016679:Genome, Viral; D008969:Molecular Sequence Data; D010802:Phylogeny; D017801:Plum Pox Virus / Q000235:genetics* / Q000302:isolation & purification*; D016865:Reassortant Viruses; D011994:Recombinant Proteins; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D011994:Recombinant Proteins; D014764:Viral Proteins