FIG 1.

JHM.SD is less sensitive than A59 to bafilomycin A. Pretreated L2 cells were infected with rJHM.SD-fluc or rA59-fluc at an approximate multiplicity of infection (MOI) of 0.5 and then assayed for luciferase activity 7 hpi as described in Materials and Methods. In parallel, cells were infected and then treated with DMSO-bafilomycin A beginning 1 h postinfection, and the pretreatment effect (relative to DMSO alone for each virus) was divided by the corresponding posttreatment effect to correct for posttreatment effects. (Top and middle) An asterisk indicates significant difference between the 0 and 10 nM or 100 nM treatment within each virus (2-way ANOVA with Dunnett's multiple comparisons of simple effects within columns). (Bottom) After correction, the effect of bafilomycin A was significantly smaller for JHM.SD than for A59 (n = 5; P < 0.0001 for the bafilomycin A effect, P < 0.0001 for the virus strain effect, and P < 0.0008 for the interaction, all by 2-way ANOVA). Symbols: *, significant difference (Tukey's multiple comparisons between all cell means) within each MHV strain between the bafilomycin A treatment and the 0 nM bafilomycin A control; #, significant difference between JHM.SD and A59 at the indicated bafilomycin A concentration (Tukey's multiple comparisons between all cell means). Data shown are representative of 3 independent experiments with n = 5 technical replicates.