FIG. 3.

Host range and temperature sensitivity analysis of SeV mutants. (A) IF infectious focus assay to analyze SeV r1782A (compared to the SeV rWT) for hr and ts phenotypes. Infectious virus foci were visualized by IF using anti-SeV primary rabbit antibodies and anti-rabbit IgG-fluorescein isothiocyanate antibodies on fixed and permeabilized Vero or HEp-2 cells infected with SeV r1782A or the rWT at 34°C or 40°C. (B) GFP fluorescence focus assay to analyze SeV rWT-GFP, r1805A-GFP, and r1806A-GFP viruses carrying the GFP gene upstream of the NP gene for hr and ts phenotypes. Assays were done using Vero or HEp-2 cells at 34°C or 40°C. Infectious virus foci were visualized by microscopy at 48 or 72 h p.i., as indicated, using fluorescence (top) or bright-field (bottom) channels. Virus dilutions are indicated.