Positive-strand RNA viruses comprise over one third of all virus genera and include important human pathogens such as hepatitis C virus, dengue virus, chikungunya virus, and West Nile virus [15] . Brome mosaic virus (BMV), a member of the alphavirus-like superfamily of human, plant, and animal viruses, has been used as a model system to study gene expression, RNA replication and virus-host interactions of positive-strand RNA viruses [1, 2, 8, 10, 16] . BMV has three genomic RNAs and one subgenomic (sg) mRNA. Genomic RNAs 1 and 2 encode the multifunctional replication proteins 1a and 2a polymerase (2a Pol ), respectively, which are required for RNA replication [17, 18, 19] . Genomic RNA3 encodes the 3a movement protein, required for infection spread in plants. A sg mRNA, RNA4, encodes the viral coat protein and is produced from the (2)RNA3 replication intermediate. BMV RNA replication and encapsidation can be recapitulated in the yeast Saccharomyces cerevisiae by expressing the viral replication and/or capsid proteins together with at least one genomic RNA template [20, 21, 22] . The ability of BMV to duplicate nearly all major replication features of its natural plant hosts in yeast, combined with yeast genetics, has advanced our understanding of BMV replication and virus-host interactions [1, 2, 9] .