title: Poinsettia latent virus is not a cryptic virus, but a natural polerovirus-sobemovirus hybrid.
abstract: The biochemical and genetic features of Poinsettia latent virus (PnLV, formerly named Poinsettia cryptic virus), which is spread worldwide in commercial cultivars of Euphorbia pulcherrima without inducing symptoms, have been determined using virus-purification, immunological techniques, electron microscopy, cloning, and sequencing. PnLV was found to be a chimeric virus with one 4652 bases, plus strand RNA showing a close relationship to poleroviruses within the first three quarters of its genome but to sobemoviruses in the last quarter. Thus, we propose to classify this virus as "polemovirus". Similarities of protein and nucleic acid sequences at the 5' and extreme 3' end of its RNA suggest a replication mode like that of poleroviruses, whereas the coat protein sequence is closely related to that of sobemoviruses. Consistent with these results, PnLV forms stable icosahedra of 34 nm in diameter. The consequences for the taxonomy of PnLV and for gardeners' practice are discussed.
authors.affiliation: Biologisches Institut, Abteilung für Molekularbiologie und Virologie der Pflanzen, Universität Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Aus dem Siepen
authors.forename: Jens O
authors.initials: JO
authors.lastname: Pohl
authors.forename: Bong-Jin
authors.initials: BJ
authors.lastname: Koo
authors.forename: Christina
authors.initials: C
authors.lastname: Wege
authors.forename: Holger
authors.initials: H
authors.lastname: Jeske
mesh_terms: D001483:Base Sequence; D036022:Capsid Proteins / Q000235:genetics; D003001:Cloning, Molecular; D019665:Euphorbiaceae / Q000821:virology*; D017793:Luteovirus / Q000502:physiology; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012328:RNA Viruses / Q000737:chemistry / Q000145:classification* / Q000502:physiology; D012367:RNA, Viral / Q000737:chemistry; D011995:Recombination, Genetic; D016415:Sequence Alignment; D019183:Tombusviridae / Q000502:physiology; D014779:Virus Replication
chemical_list: D036022:Capsid Proteins; D012367:RNA, Viral