Notes on Genus: Pestivirus

icosahedra
icosahedra

Type member: Bovine viral diarrhea virus 1

Contents

General Description

This is one of the genera in the family Flaviviridae and consists of those viruses with a genome of >12kb that encodes four structural proteins (coat protein and three membrane proteins). They also differ from members of other genera in having a leader protease at the N-terminus of the polyprotein, upstream of the coat protein cistron. The name is from the Latin pestis = plague, from the symptoms caused.

Morphology

Virions enveloped and spherical about 40-60 nm in diameter. Mature virions contain three virus-encoded membrane proteins (Ems, E1 and E2) in addition to the coat protein.

Genome

Monopartite positive sense single-stranded RNA 12-13kb in length, with no 3'-polyA tail.

Genus Genomic Organization

There is a single polyprotein of 435-450 kDa that is subsequently processed into a number of structural and non-structural proteins.

Type Member Genomic Organization

There is a single polyprotein of about 449.2 kDa that is subsequently processed into a number of structural and non-structural proteins:
  • Npro leader protease
  • Coat protein C
  • Envelope glycoprotein Ems
  • Envelope glycoprotein E1
  • Envelope glycoprotein E2
  • p7 protein of unknown function
  • Non-structural protein 2
  • Non-structural protein 3 (protease and helicase activity)
  • Non-structural protein 4a
  • Non-structural protein 4b
  • Non-structural protein 5a
  • Non-structural protein 5b (polymerase)