School of Biotechnology and Graduate School of Biochemistry, Yeungnam University, Gyeongsan, Republic of Korea.
FEBS Lett. 2012 Sep 21;586(19):3085-9. doi: 10.1016/j.febslet.2012.07.056. Epub 2012 Jul 28.
DNA fragmentation is the hallmark of apoptotic cells and mainly mediated by the DNA fragmentation factor DFF40(CAD)/DFF45(ICAD). DFF40 is a novel nuclease, whereas DFF45 is an inhibitor that can suppress the nuclease activity. Apoptotic DNA fragmentation in the fly is controlled by four DFF-related proteins, known as Drep1, 2, 3 and 4. However, the functions of Drep2 and Drep3 are totally unknown. Here, we found that Drep2 is a novel nuclease whose activity is inhibited by Drep3 through a tight interaction with the CIDE domain. Our results suggest that the fly has dual apoptotic DNA fragmentation systems: Drep1: Drep4 and Drep2: Drep3 complexes.
DNA 碎片化是细胞凋亡的标志，主要由 DNA 碎片化因子 DFF40（CAD）/DFF45（ICAD）介导。DFF40 是一种新型核酸酶，而 DFF45 是一种抑制剂，可以抑制核酸酶活性。在果蝇中，凋亡性 DNA 碎片化受四种 DFF 相关蛋白（称为 Drep1、2、3 和 4）控制。然而，Drep2 和 Drep3 的功能完全未知。在这里，我们发现 Drep2 是一种新型核酸酶，其活性受到 Drep3 的抑制，通过与 CIDE 结构域的紧密相互作用。我们的结果表明，果蝇具有双重凋亡性 DNA 碎片化系统：Drep1：Drep4 和 Drep2：Drep3 复合物。
