Figure 5.

A, Phase-contrast micrographs of PC12 stably transfected with pcDNA3 empty vector (Control, top row) or pcDNA3–FLIP-L (FLIP, bottom row). PC12 cells were treated with complete medium (Serum, left column) or with NGF 100 ng/ml (right column) for 3 d. Scale bar, 100 μm. B, PC12 cells stably transfected with empty vector (Neo) or with SR-IκBα. Total cell lysates were analyzed by Western blot using an antibody against IκBα (top). Membranes were reprobed with anti-tubulin to normalize the loading content per lane (bottom). C, Stable Neo or SR-IκBα PC12 cells were infected with lentiviral particles either empty (Ctrl) or containing FLIP-L (FLIP-L). Two days later, cells were serum deprived, then left untreated (no NGF) or pretreated or not with 50 μm PD98059, and stimulated with 100 ng/ml NGF for 1 d, after which total neurite length was measured. Significant differences (NGF+PD98059-treated vs NGF-treated; Ctrl or FLIP-L Neo-transfected cells) are indicated (*p < 0.001, t test).