Figure 3

Subcellular distribution of gal-7 in MCF-7 cells. (A) Cytosolic and nuclear fractions were purified from control (srα) cells and MCF-7 cells expressing gal-7. Expression of gal-7 was measured in both fractions by Western blotting. β-tubulin and lamin A/C are shown as positive cytoplasmic and nuclear expression controls, respectively. (B) Similar analysis showing expression of gal-7 in purified mitochondrial fractions. β-tubulin and COX IV are shown as positive cytoplasmic and mitochondrial expression controls, respectively. (C-F) Subcellular localization of gal-7 in MCF-7 as measured by electron microscopy. Scale bars, 500 nm (C) and 100 nm (D-F). (G) Effect of gal-7 on induction of apoptosis by doxorubicin. Stable transfectants of MCF-7 cells expressing gal-7 were treated with 50 nM doxorubicin for 72 hrs at 37°C. Cells were then harvested and PARP-1 cleavage levels were assayed by Western blotting.