title: Generation of a molecular clone of an attenuated lentivirus, a first step in understanding cytopathogenicity and virulence.
abstract: Small ruminant lentiviruses infect goats and sheep, inducing clinical disease in a minority of infected animals. Following an eradication campaign, clinical cases may disappear in a population. The complete elimination of these lentiviruses is however difficult to achieve and the spreading of less virulent strains often parallels the elimination of their virulent counterparts. Here, we characterized three such strains isolated from a flock in the post-eradication phase. We completely sequenced their genomes, showing that one of the isolates was most probably the product of a recombination event between the other two viruses. By comparing the sequences of these isolates with those of virulent strains, we found evidence that particular LTR mutations may explain their attenuated phenotype. Finally, we constructed an infectious molecular clone representative of these viruses, analyzing its replication characteristics in different target cells. This clone will permit us to explore the molecular correlates of cytopathogenicity and virulence.
authors.affiliation: Institute of Virology and Immunology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
authors.forename: Laure
authors.initials: L
authors.lastname: Blatti-Cardinaux
authors.affiliation: Università degli Studi di Milano, Department of Health, Animal Science and Food Safety, via Celoria 10, 20133 Milano, Italy.
authors.forename: Giuliano
authors.initials: G
authors.lastname: Pisoni
authors.affiliation: Division of Veterinary Anatomy, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Stoffel
authors.affiliation: Institute of Virology and Immunology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
authors.forename: Reto
authors.initials: R
authors.lastname: Zanoni
authors.affiliation: Institute of Virology and Immunology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
authors.forename: Marie-Luise
authors.initials: ML
authors.lastname: Zahno
authors.affiliation: Institute of Virology and Immunology, Vetsuisse Faculty, University of Bern, Bern, Switzerland. Electronic address: bertoni@besonet.ch.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Bertoni
mesh_terms: D000818:Animals; D016088:Arthritis-Encephalitis Virus, Caprine / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D001483:Base Sequence; D002478:Cells, Cultured; D003001:Cloning, Molecular / Q000379:methods*; D003588:Cytopathogenic Effect, Viral / Q000235:genetics; D015511:Goat Diseases / Q000821:virology; D006041:Goats; D016180:Lentivirus Infections / Q000821:virology*; D008264:Macrophages / Q000821:virology; D008969:Molecular Sequence Data; D012367:RNA, Viral / Q000235:genetics*; D016415:Sequence Alignment; D017423:Sequence Analysis, RNA; D012756:Sheep; D012757:Sheep Diseases / Q000821:virology; D014790:Visna-maedi virus / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity
chemical_list: D012367:RNA, Viral
keywords: Caprine arthritis encephalitis virus; Cytopathogenicity; Electron microscopy; Infectious clone; Long terminal repeats; Molecular clone; Small ruminant lentiviruses; Transcription; Virus replication; Visna/maedi virus