Notes on Genus: Salivirus
Type member: Salivirus A
The genus Salivirus
ke virus) is one of the genera in the family Picornaviridae
. Genome organisation is fairly conserved within the family but members of this genus have a leader protease and a distinctive 2A protein which is a putative trypsin-like protease.
Virions isometric (icosahedral), not enveloped 30 nm in diameter, made of 60 units (protomers) each consisting of one molecule of each of three surface coat proteins and with a fourth internal capsid protein.
Monopartite positive sense single-stranded RNA about 8 kb in length. There is a genome-linked protein (VPg) at the 5'-terminus and a 3'-polyA tail.
Genus Genomic Organization
The RNA encodes a single polyprotein that is subsequently processed into the functional products. The major structural proteins are encoded at the N-terminus.
Type Member Genomic Organization
The genome of about 8,000 nucleotides is translated into a single polyprotein, which is subsequently processed into twelve products:
||Coat protein VP4+VP2 precursor|
||Coat protein VP3 (surface capsid protein)|
||Coat protein VP1 (surface capsid protein)|
||non-structural protein (protease)|
||Genome-linked protein (VPg)|