FIG 1 .

Infection with MHV or SARS CoV induces continuous membrane ruffling. (A) DBT cells were infected with MHV-Δ2-GFP3 at an MOI of 1 PFU/cell and imaged from 4 to 12 hpi. The small panels to the right are enlargements showing details of the white-boxed area. Green fluorescence indicates nsp3. Black arrowheads denote vesicles. White arrowheads follow the evolution of a vesicle over time. See Movie S1A to C in the supplemental material. (B) Vesicle diameter was measured in five movies of infected cells. MOI = 1 PFU/cell, n = 386 vesicles. (C, D) DBT cells were infected with MHV A59 at an MOI of 1 PFU/cell for 8 h. DBT-hACE2 cells were infected with SARS CoV at an MOI of 0.1 PFU/cell for 24 h. Cells were fixed with 10% formalin and stained for F-actin (green). The arrow indicates a ruffle (C). Every third infected (or mock-infected) cell was imaged and scored for ruffling by three blinded reviewers. Data are represented as the means ± the standard errors of the means of two replicates performed in duplicate. Significance was assessed by one-way ANOVA with Dunnett’s post hoc test. n = ≥30 fields per replicate. *, P<0.05.