Structure, restriction map and infectivity of the genomic and replicative forms of AaPV DNA

We have characterized the genomic and replicative form (RF) DNA of the Aedes albopictus Parvovirus (AaPV), a virus isolated from a chronically infected C6/36 clone of Aedes albopictus cell line [22]. The genome of AaPV virions is a single-stranded linear DNA molecule approximately 4.2 kb in length, essentially (about 90%) encapsidated as minus strand. A restriction map of the RF DNA isolated from infected C6/36 cells was established. Among the 23 restriction enzymes tested, 14 cleaved the AaPV RF DNA and 30 restriction sites were mapped and oriented with respect to the viral genomic DNA. Both viral and RF DNAs were found infectious when transfected to virus-free C6/36 cells. The asymmetrical encapsidation of the viral genome is a property common to most vertebrate autonomous parvoviruses but rather unusual among densoviruses. Both by its small size, the asymmetrical mode of encapsidation and the restriction map, the AaPV genome resembles that of the Aedes Densonucleosis virus [1].