Proteins encoded in the 5' region of the pestivirus genome--considerations concerning taxonomy.

The first protein encoded within the pestivirus open reading frame is a nonstructural protein which removes itself from the polyprotein by autoproteolytic cleavage. The following nucleocapsid protein ends just before a putative signal sequence preceding three glycosylated proteins. All three glycoproteins are part of the viral envelope and exist in the form of disulfide-linked dimers. Pestiviruses have recently been reclassified as members of the family Flaviviridae which now comprises three genera, namely flavivirus, hepatitis C virus group and pestivirus. All members of the family have certain characteristics in common like the overall genome organization and the strategy of gene expression. Major differences exist, however, between the genera; the most obvious ones concern proteins encoded in the 5' region of the respective genomes.