title: Duplicated sequence motif in the long terminal repeat of maedi-visna virus extends cell tropism and is associated with neurovirulence.
abstract: Maedi-visna virus (MVV) is a lentivirus of sheep causing chronic inflammatory disease of the lungs (maedi) and the nervous system (visna). We have previously shown that a duplicated sequence in the long terminal repeat (LTR) of MVV is a determinant of cell tropism. Here, we demonstrate that deletion of a CAAAT sequence from either one of the repeats resulted in poor virus growth in sheep choroid plexus cells. A duplication in the LTR encompassing the CAAAT sequence was found in four neurological field cases that were sequenced, but no duplication was present in the LTRs from seven maedi cases; one maedi isolate was mixed. These results indicate that the duplication in the LTR is associated with neurovirulence.
authors.affiliation: Institute for Experimental Pathology, University of Iceland, Keldur v/Vesturlandsveg, 112 Reykjavik, Iceland.
authors.forename: Thórdur
authors.initials: T
authors.lastname: Oskarsson
authors.forename: Hulda S
authors.initials: HS
authors.lastname: Hreggvidsdóttir
authors.forename: Gudrún
authors.initials: G
authors.lastname: Agnarsdóttir
authors.forename: Sigrídur
authors.initials: S
authors.lastname: Matthíasdóttir
authors.forename: Margrét H
authors.initials: MH
authors.lastname: Ogmundsdóttir
authors.forename: Stefán R
authors.initials: SR
authors.lastname: Jónsson
authors.forename: Gudmundur
authors.initials: G
authors.lastname: Georgsson
authors.forename: Sigurdur
authors.initials: S
authors.lastname: Ingvarsson
authors.forename: Olafur S
authors.initials: OS
authors.lastname: Andrésson
authors.forename: Valgerdur
authors.initials: V
authors.lastname: Andrésdóttir
mesh_terms: D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D002831:Choroid Plexus / Q000166:cytology / Q000821:virology*; D008969:Molecular Sequence Data; D011021:Pneumonia, Progressive Interstitial, of Sheep / Q000821:virology; D017384:Sequence Deletion; D034561:Sheep, Domestic; D020079:Terminal Repeat Sequences / Q000235:genetics*; D016182:Visna / Q000821:virology; D014790:Visna-maedi virus / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity* / Q000502:physiology*