Expression and packaging phenotypes of FHV CP (FCP) via BMV replication. (A) Schematic representation of a T-DNA construct of BMV RNA3 (B3) and its subgenomic RNA (sgB4/FCP) harboring the FCP ORF. The length of the B3 chimera and its sgB4 and the number of nonviral nucleotides left after self-cleavage by the ribozyme (shown in parentheses) are indicated. (B and C) Northern blotting analysis of progeny RNA. N. benthamiana leaves were infiltrated with the indicated mixture of agrotransformants. Total and virion RNAs were subjected to multiple Northern blotting analyses and hybridized with the indicated riboprobes as described in the legend to Fig. 1. The positions of progeny RNA of wt FHV, wt BMV, B3/FCP, and sgB4/FCP are shown. The band at the B2 position is of a higher intensity since B2 (2,864 nt) and B3/FCP (2,790 nt) comigrate, and in panel C, lanes 1, 2, and 3 were exposed for 4 h, 3 h, and 1 h, respectively, to reveal bands of interest.