Figure 3.

[8-³H]PCV and FPCV accumulation in stably transfected cells. The C6, C6-stb-tk+, and C6-stb-sr39tk+ cell lines were incubated with either [8-³H]PCV (Upper) or FPCV (Lower) for the times shown. Values are net accumulation of each tracer (dpm cells/dpm medium at time zero), normalized both to μg of total protein and to relative TK levels as determined from a Western blot, as a function of time. The error bars represent the standard error for triplicate determinations. *, A significant difference (P < 0.05) compared to C6 control cells. ∧, A significant difference (P < 0.05) compared to both C6 and C6-stb-tk+ cells.