FIG. 2.

Gel electrophoresis of lysates prepared from Drosophila cells transfected with wt FHV RNA1 and wt or mutant FHV transcript RNA2. Cell monolayers containing 10⁷ Drosophila cells were transfected with a mixture of approximately 100 ng of RNA1 and 100 ng of RNA2, as described in Materials and Methods. At 24 h after transfection, cells were dislodged into the growth medium, collected by centrifugation, and washed twice with 0.5 ml of phosphate-buffered saline (PBS). The final cell pellet was resuspended in 100 μl of PBS, mixed with an equal volume of 2× electrophoresis buffer, and heated to 95°C for 10 min. Aliquots of 10 μl (approximately 5 × 10⁵ cells) were electrophoresed through an SDS–12% polyacrylamide gel, followed by staining with Coomassie brilliant blue. Gamma peptide migrated off the gel under the conditions used. Lane 1, molecular weight markers; lane 2, lysate from mock-transfected cells; lane 3, lysate from cells transfected with wt RNA1 and wt RNA2 (note that wt protein alpha comigrates with a cellular protein, probably actin); lane 4, lysate from cells transfected with wt RNA1 and Δγ363 RNA2; lane 5, lysate from cells transfected with wt RNA1 and Δγ381 RNA2.