Fig. 2. Age-dependent dislocalization of nuclear BAF in normal cells. (A) Localization of BAF in TIG-1 cells with different ages (left panels). Right panels represent FACS profiles showing cell cycle stages of cells corresponding to the left panels. Scale, 40 µm. Arrows represent cells with prominent nuclear signals, the asterisk indicates cells with uniform signaling and arrowheads represent cells with prominent cytoplasmic signals. (B) Proportions of cell populations with different BAF localization: Nuc>Cyto, Nuc=Cyto and Nuc<Cyto represent cells with nucleus-positive, uniform and cytoplasm-positive BAF, respectively. The proportion of cell populations was determined from 19, 11 and 8 independent experiments for cells of PD15, PD47 and PD63, respectively. Data are mean ± s.d. of at least 100 cells for each experiment. (C) Western blotting for BAF in young (left) and old (right) TIG-1 cells. (D) Proportion of cell cycle stages of young proliferating cells with nuclear BAF (nucleus positive and uniform). The proportion of cells with no nuclear BAF (nucleus negative) was less than 1% in young cells, and thus ignored. The results were obtained from 15 independent experiments; at least 100 cells were examined in each experiment. (E) Cell cycle stages of old TIG-1 cells (PD63) with nuclear BAF (corresponding to the nucleus positive and uniform populations) were examined in six independent experiments; at least 100 cells were counted in each experiment. (F) Cell cycle stages of old TIG-1 cells (PD63) with no nuclear BAF (corresponding to the cytoplasm positive population) were examined in five independent experiments; at least 100 cells were counted in each experiment. No S-phase cells were observed in cells with nucleus-negative BAF, suggesting that nuclear BAF is required for S-phase. Data are mean ± s.d. for D-F.