A Replicon Trans-Packaging System Reveals the Requirement of Nonstructural Proteins for the Assembly of Bovine Viral Diarrhea Virus (BVDV) Virion

Authors

Delin Liang, Ceres, Inc. 1535 Rancho Conejo Blvd, Thousand Oaks, CA 91320, USA
Limei Chen, Influenza Division, NCIRD, CCID, Centers for Disease Control and Prevention, 1600 Clifton Road - Mail Stop G-16, Atlanta, GA 30333, USA
Israrul H. Ansari, University of Nebraska - LincolnFollow
Laura H. V. G. Gil, Oswaldo Cruz Foundation (FIOCRUZ), Aggeu Magalhães Center, Av. Professor Moraes Rego, s/n CEP- 50670-420; Recife-PE, Brazil
Christina L. Topliff, University of Nebraska - LincolnFollow
Clayton L. Kelling, University of Nebraska - LincolnFollow
Ruben O. Donis, Influenza Division, NCIRD, CCID, Centers for Disease Control and PreventionFollow

Date of this Version

5-10-2009

Comments

Published in Virology 387:2 (May 10, 2009), pp. 331–340; doi 10.1016/j.virol.2009.02.019 Copyright © 2009 Elsevier Inc. Used by permission.

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, Erns, 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.