title: Adaptation of lettuce mosaic virus to Catharanthus roseus involves mutations in the central domain of the VPg.
abstract: An isolate of Lettuce mosaic virus (LMV, a Potyvirus) infecting Madagascar periwinckle (Catharanthus roseus) was identified and characterized by Illumina deep sequencing. LMV-Cr has no close affinities to previously sequenced LMV isolates and represents a novel, divergent LMV clade. Inoculation experiments with other representative LMV isolates showed that they are unable to infect C. roseus, which was not known to be a host for LMV. However, three C. roseus variants of one of these isolates, LMV-AF199, could be selected and partially or completely sequenced. These variants are characterized by the accumulation of mutations affecting the C-terminal part of the cylindrical inclusion (CI) helicase and the central part of the VPg. In particular, a serine to proline mutation at amino acid 143 of the VPg was observed in all three independently selected variants and is also present in the LMV-Cr isolate, making it a prime candidate as a host-range determinant. Other mutations at VPg positions 65 and 144 could also contribute to the ability to infect C. roseus. Inoculation experiments involving a recombinant LMV expressing a permissive lettuce eukaryotic translation initiation factor 4E (eIF4E) suggest that eIF4E does not contribute to the interaction of most LMV isolates with C. roseus.
authors.forename: Laurence
authors.initials: L
authors.lastname: Svanella-Dumas
authors.forename: Eric
authors.initials: E
authors.lastname: Verdin
authors.forename: Chantal
authors.initials: C
authors.lastname: Faure
authors.forename: Sylvie
authors.initials: S
authors.lastname: German-Retana
authors.forename: Patrick
authors.initials: P
authors.lastname: Gognalons
authors.forename: Jean Luc
authors.initials: JL
authors.lastname: Danet
authors.forename: Armelle
authors.initials: A
authors.lastname: Marais
authors.forename: Thierry
authors.initials: T
authors.lastname: Candresse
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D001483:Base Sequence; D030008:Catharanthus / Q000821:virology*; D004265:DNA Helicases / Q000235:genetics / Q000378:metabolism; D039561:Eukaryotic Initiation Factor-4E / Q000235:genetics / Q000378:metabolism; D016679:Genome, Viral / Q000235:genetics*; D058507:Host Specificity; D018545:Lactuca / Q000821:virology*; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D010935:Plant Diseases / Q000821:virology*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D017800:Potyvirus / Q000235:genetics* / Q000502:physiology; D017422:Sequence Analysis, DNA; D014764:Viral Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D039561:Eukaryotic Initiation Factor-4E; D010940:Plant Proteins; D014764:Viral Proteins; D004265:DNA Helicases