Notes on Genus: Parvovirus
Type member: Mice minute virus
This is one of the genera in the subfamily Parvovirinae
, the vertebrate pathogens in the family Parvoviridae
. Members are distinguished from those of the other genera by the presence of hairpin structures at both ends of the genome, the two mRNA promoters and a single polyadenylation site.
Virions isometric (icosahedral), not enveloped, 18-26 nm in diameter, made of 60 units of the capsid protein.
Linear, single-stranded monopartite DNA, about 5.1 kb long with hairpin structures at both ends of the genome and the two mRNA promoters. Depending on the species, negative strand DNA may occur exclusively, or in the majority of virions.
Genus Genomic Organization
As in other members of the subfamily, there are two major ORFs on the same strand. These encode the non-structural (replication) protein and the capsid protein. mRNA splicing may result in products that differ from those of simple computer predictions but which have not always been experimentally determined. The capsid protein may also undergo proteolytic cleavage.
Type Member Genomic Organization
There are 2 major ORFs in the same orientation and three major protein products:
- Non-structural protein NS1, 76.2 kDa
- Capsid protein VP1 (80.1 kDa) translated from a spliced mRNA
- Capsid protein VP2 (64.5 kDa) with the same C-terminus as VP1