Fig. 7. Fas-induced apoptosis in Jurkat cells is potentiated by ectopically introduced Flag-tagged p38
and suppressed by the dominant negative variant p38
-AGF. (A) Immunoblot analysis using anti-p38
antibody (lanes 1-3) and anti-Flag antibody (lanes 4-6) demonstrate the expression of transfected Flag-p38
(lanes 2,5) and Flag-p38
-AGF (lanes 3,6). (B) Cells expressing Flag-p38
displayed threefold greater sensitivity to Fas-mediated apoptosis than the native Jurkat cells (30.6±1.1 vs 11.4±0.6% apoptotic cells, lanes 3 and 2). By contrast, Flag-p38
-AGF expression rendered the cells resistant to Fas-activation (lane 4). (C) The decrease in mitochondrial membrane potential (
m) in Jurkat cells (37±2.6%) was increased in cells expressing Flag-p38
(66±1.2%) but was suppressed by Flag-p38
-AGF (10.7±0.7%). The transfected proteins did not affect the basal levels of apoptosis or 
m (lanes 1,5 and 6).