Figure 6.

Intracellular distribution of vRNA-ΔM. Infected protoplasts were fixed and hybridized with a fluorescein-RNA probe to localize vRNA. Fluorescence was visualized by confocal microscopy of optical sections with a focal depth of 0.8 μm. (A–C) Accumulation of vRNA-ΔM at early stages of infection in vesicle-like structures surrounding the nucleus and in small cytoplasmic patches (A) and in stacks of tubular strands (B). vRNA-ΔM was also associated with small vesicles surrounding the nucleus and throughout the cytoplasm (C). At midstages of infection, vRNA-ΔM was observed in bright fluorescent spots interconnected by short filaments (D) and in stacks of lamellar structures (E). At late stages of infection (F), fluorescent signal was observed only in small, intensely labeled spots around the nucleus and scattered throughout the cytoplasm. Note the absence of vRNA-ΔM in association with large fluorescent bodies or with clearly defined filaments. A corresponds to the projection of 12 serial optical sections, while B–F correspond to single optical sections. N, nucleus. Bars: (A, B, E, and F) 10 μm; (C and D) 5 μm.