Fig. 5. Pin1 depletion induces apoptosis in interphase. A, phosphorylation of histone H3 correlates with mitotic phases. Fixed HeLa cells were double-stained with DAPI and with an antibody recognizing phosphorylated histone H3. The nuclei of cells in prophase (P), metaphase (M), and telophase (T) are shown. B, mitotic cell death. HeLa cells were incubated for 48 h with 50 nM Taxol and double-stained as in A. C, Pin1 depletion induces apoptosis in interphase. Seventy-two h after transfection with GFP and Pin1 antisense, fixed cells were double-stained with DAPI and with an antibody recognizing phosphorylated histone H3. II and IV, same images as in I and III superimposed with GFP-emitted green fluorescence. Arrows, transfected apoptotic cells.