Dual apoptotic DNA fragmentation system in the fly: Drep2 is a novel nuclease of which activity is inhibited by Drep3

► We found that CIDE domain can be self-oligomerized by studying Drep2 CIDE domain. ► We found that Drep2 has nuclease activity. ► Finally, we found that Drep2 nuclease activity was inhibited by Drep3 by direct interaction via CIDE domain.