Infectious bursal disease virus VP3 upregulates VP1-mediated RNA-dependent RNA replication

Genome replication is a critical step in virus life cycles. Here, we have analyzed the role of the infectious bursal disease virus (IBDV) VP3, a major component of IBDV ribonucleoprotein complexes, on the regulation of VP1, the virus-encoded RNA-dependent RNA polymerase (RdRP). Data show that VP3, as well as a peptide mimicking its C-terminal domain, efficiently stimulate the ability of VP1 to replicate synthetic single stranded RNA templates containing the 3 -UTRs from the IBDV genome segments.