FIG 1.

P58 is required for RNA2 accumulation. (A) Schematic representations of BPMV RNA1, RNA1m (a nonreplicating RNA1 mutant), RNA2-GFP (R2G), and the series of R2G mutants used in this study, accompanied by images of lima bean cotyledons bombarded with these constructs. The mutation contained in RNA1m (GDD → AAH) is highlighted in a gray box. Details of RNA2 mutants are provided on their respective diagrams. The images of bombarded cotyledons were taken at 48 h postbombardment, using cameras equipped with a dissecting or epifluorescence microscope. Some infection foci are highlighted with arrows. (B) Replication of BPMV in bombarded cotyledons as measured by semiquantitative RT-PCR to detect (−) RNA1 (top panel) and (−) RNA2 (middle panel). The relative accumulation levels of the mutants were calculated by using that of wild-type R2G as the reference (arbitrarily set as 1). An RT-PCR fragment of lima bean actin mRNA was used as a control.