The minute virus of mice P39 transcription unit can encode both capsid proteins

The right-hand 80% of the genome of minute virus of mice (MVM) was cloned into the bovine papillomavirus type I shuttle vector and used to transfect mouse C127 cells. Transformed lines were isolated that efficiently produce both authentic MVM capsid proteins at a ratio similar to that seen in a normal viral infection, and these proteins assemble into intact empty virions. The only transcription of MVM sequences detected in these lines was representative of the viral P39 transcription unit, which therefore contains sufficient information to encode both authentic capsid proteins at the same regulated ratio seen in an infected cell.</jats:p

Generation and characterization of a temperature-sensitive mutation in the NS-1 gene of the autonomous parvovirus minute virus of mice

In-phase single-codon insertion mutations were constructed in the open reading frames of the NS-1 and NS-2 genes of the autonomous parvovirus minute virus of mice. A viral mutant containing an isoleucine insertion exclusively within NS-1 between residues 229 and 230 was isolated that produced approximately 3 orders of magnitude fewer plaques at 39 degrees C than at 32 degrees C. Preliminary characterization of the mutant demonstrated that the NS-1 gene product is independently required for both genome amplification and the regulation of the temporal expression between the two viral transcription units during lytic infection.</jats:p