title: Biological, Serological, and Molecular Characterization of a Highly Divergent Strain of Grapevine leafroll-associated virus 4 Causing Grapevine Leafroll Disease.
abstract: The complete genome sequence of a highly divergent strain of Grapevine leafroll-associated virus 4 (GLRaV-4) was determined using 454 pyrosequencing technology. This virus, designated GLRaV-4 Ob, was detected in Vitis vinifera 'Otcha bala' from our grapevine virus collection at Agroscope. The GLRaV-4 Ob genome length and organization share similarities with members of subgroup II in the genus Ampelovirus (family Closteroviridae). Otcha bala was graft-inoculated onto indicator plants of cultivar Gamay to evaluate the biological properties of this new strain, and typical leafroll symptoms were induced. A monoclonal antibody for the rapid detection of GLRaV-4 Ob by enzyme-linked immunosorbent assay is available, thus facilitating large-scale diagnostics of this virus. Based on the relatively small size of the coat protein, the reduced amino acid identity and the distinct serological properties, our study clearly shows that GLRaV-4 Ob is a divergent strain of GLRaV-4. Furthermore, molecular and serological data revealed that the AA42 accession from which GLRaV-7 was originally reported is in fact co-infected with GLRaV-4 Ob and GLRaV-7. This finding challenges the idea that GLRaV-7 is a leafroll-causing agent.
authors.affiliation: First and fourth authors: Agroscope-Virology and Phytoplasmology, Nyon, Switzerland; second author: Swiss Tropical and Public Health Institute-Virology, Basel, Switzerland; and third author: Agroscope-Molecular Diagnostics, Genomics and Bioinformatics, Waedenswil, Switzerland.
authors.forename: Jean-Sébastien
authors.initials: JS
authors.lastname: Reynard
authors.affiliation: First and fourth authors: Agroscope-Virology and Phytoplasmology, Nyon, Switzerland; second author: Swiss Tropical and Public Health Institute-Virology, Basel, Switzerland; and third author: Agroscope-Molecular Diagnostics, Genomics and Bioinformatics, Waedenswil, Switzerland.
authors.forename: Pierre H H
authors.initials: PH
authors.lastname: Schneeberger
authors.affiliation: First and fourth authors: Agroscope-Virology and Phytoplasmology, Nyon, Switzerland; second author: Swiss Tropical and Public Health Institute-Virology, Basel, Switzerland; and third author: Agroscope-Molecular Diagnostics, Genomics and Bioinformatics, Waedenswil, Switzerland.
authors.forename: Jürg Ernst
authors.initials: JE
authors.lastname: Frey
authors.affiliation: First and fourth authors: Agroscope-Virology and Phytoplasmology, Nyon, Switzerland; second author: Swiss Tropical and Public Health Institute-Virology, Basel, Switzerland; and third author: Agroscope-Molecular Diagnostics, Genomics and Bioinformatics, Waedenswil, Switzerland.
authors.forename: Santiago
authors.initials: S
authors.lastname: Schaerer
mesh_terms: D001483:Base Sequence; D017790:Closterovirus / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification* / Q000648:ultrastructure; D004797:Enzyme-Linked Immunosorbent Assay; D016679:Genome, Viral / Q000235:genetics*; D059014:High-Throughput Nucleotide Sequencing; D008969:Molecular Sequence Data; D010802:Phylogeny; D010935:Plant Diseases / Q000821:virology*; D018515:Plant Leaves / Q000821:virology; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics; D017423:Sequence Analysis, RNA; D027843:Vitis / Q000821:virology*
chemical_list: D012367:RNA, Viral