FIGURE 6.
Ad.mda-7 induces the activation of the Bcl-x(s)/proximal 5′ splice site of Bcl-x pre-mRNA independent of de novo ceramide generation. A and B, A549 cells (1.2 × 105) were pre-treated with 100 μm fumonisin B1 (FB1) (A) or 100 nm myriocin (Myr) (B) for 4 h, followed by transduction with 150 MOI of either Ad.mda-7 or Ad.CMV control virus. After 24 h, total RNA was extracted and subjected to quantitative/competitive RT-PCR analysis of Bcl-x splice variants. The ratio of Bcl-x(L) to Bcl-x(s) mRNA (Ratio (L)/(s)) was determined by densitometric analysis of RT-PCR fragments (p < 0.01, n = 6). Data are expressed as mean ± S.D. and are representative of at least three separate determinations on two separate occasions