title: A replicon trans-packaging system reveals the requirement of nonstructural proteins for the assembly of bovine viral diarrhea virus (BVDV) virion.
abstract: A selective trans-packaging system was developed to produce and isolate bovine viral diarrhea virus (BVDV) pseudo-particles with complementing reporter replicons and their packaging proteins expressed in trans with recombinant vaccinia virus. The encapsidation of replicon rNS3-5B was dependent not only on the in trans expression of structural proteins C, E(rns), E1 and E2, but also the nonstructural proteins, p7 and contiguous precursor NS2-3-4A. Nonstructural p7, NS4B, NS5A or NS5B could be expressed in cis and in trans with precursor NS2-3-4A without significantly affecting virion assembly efficiency. NS2-3-4A was identified as an in trans functional precursor in virion assembly. BVDV genomes with mutant NS5B, which did not undergo active replication, were packaged 5-fold less efficiently than the intact genomes demonstrating the importance of replication in virion packaging. These results suggest that genome replication and assembly are closely associated, consistent with a model in which these two steps are coupled for maximum efficiency.
authors.affiliation: Department of Veterinary and Biomedical Sciences, University of Nebraska-Lincoln, 68583-0905, USA.
authors.forename: Delin
authors.initials: D
authors.lastname: Liang
authors.forename: Limei
authors.initials: L
authors.lastname: Chen
authors.forename: Israrul H
authors.initials: IH
authors.lastname: Ansari
authors.forename: Laura H V G
authors.initials: LH
authors.lastname: Gil
authors.forename: Christina L
authors.initials: CL
authors.lastname: Topliff
authors.forename: Clayton L
authors.initials: CL
authors.lastname: Kelling
authors.forename: Ruben O
authors.initials: RO
authors.lastname: Donis