... role of mitochondria in the apoptotic-likeprogrammed nuclear death of Tetrahymena thermophilaTakashi Kobayashi and Hiroshi EndohDivision of Life Science, Graduate School of Natural Science and ... 3, 4, and 5, respectively), 1, 5, and 10 mM EDTA (lanes 6, 7, and 8, respectively), and 0.1, 1, and 5 mM ZnCl2(lanes 9, 10, and 11,respectively) were assayed at 30 °C for 120 min. A standard ... concen-trations (5 and 10 mm)ofMg2+inhibited the DNAcleavage activity (Fig. 4C, lane 4 and 5) and weak inhi-bition was observed even in 1 mm of Mg2+(comparelane 2 and 3 in Fig. 4C), indicating...