FIG 6.

HSV-1 ICP27 deletion mutants dAc and d2-3 are deficient in viral release. (A) Schematic diagram of mutations in viable HSV-1 ICP27 mutants. Dashed lines represent deletions, and the vertical line in the M50T bar represents a point mutation at residue 50. The capacities of the viruses to form comet-like plaques are indicated. (B) Plaque morphology phenotype of d2-3. Virus stocks were allowed to form plaques on Vero cells in liquid medium containing 1% HS. The monolayers were fixed and stained 4 days p.i. (C) dAc and d2-3 are defective in release. Vero cells were infected in triplicate with 5 PFU/cell of KOS1.1 and dAc. At 24 h p.i., supernatant and cells were harvested and titers were determined separately. The percent released and total yields were determined. (D) d2-3 is defective in release. Analysis was performed as for panel C. Statistical analyses in panels C and D were performed using the Student t test; error bars denote standard errors of the means. **, P < 0.01; ***, P < 0.001.