Sai Takafumi, Matsuda Fuko, Goto Yasufumi, Maeda Akihisa, Sugimoto Miki, Gao Hong-Mei, Kabir Abul Khair Mohammad Ahan, Li Jun-You, Manabe Noboru
Animal Resource Science Center, The University of Tokyo, Kasama 319-0206, Japan.
J Reprod Dev. 2012;58(1):112-6. doi: 10.1262/jrd.11-121h. Epub 2011 Nov 4.
In mitochondrion-dependent type II apoptosis, BH3-interacting domain death agonist (BID) and BCL-2-associated X protein (BAX) promote death ligand and receptor-mediated cell death. In porcine ovaries, the levels of BID and BAX increase in follicular granulosa cells during atresia. In the present study, to confirm the pro-apoptotic activity of BID and BAX in granulosa cells, we examined the effect of RNA interference of BID or BAX on apoptosis using a human ovarian granulosa tumor cell line, KGN. By reverse transcription polymerase chain reaction (RT-PCR) and Western blotting, expression of BID and BAX was detected in KGN cells. Then, we suppressed BID and BAX mRNA expression in KGN cells using small interfering RNA (siRNA). When BID or BAX was suppressed, a significant decrease in the apoptotic cell rate was noted. In granulosa-derived cells, BID and BAX showed pro-apoptotic activity. These results suggest that BID and BAX act as signal-transducing factors in mitochondrion-dependent type II apoptosis.
在依赖线粒体的II型凋亡中，BH3相互作用结构域死亡激动剂（BID）和BCL-2相关X蛋白（BAX）促进死亡配体和受体介导的细胞死亡。在猪卵巢中，闭锁期间卵泡颗粒细胞中BID和BAX的水平升高。在本研究中，为了证实BID和BAX在颗粒细胞中的促凋亡活性，我们使用人卵巢颗粒细胞瘤细胞系KGN检测了BID或BAX的RNA干扰对凋亡的影响。通过逆转录聚合酶链反应（RT-PCR）和蛋白质印迹法，在KGN细胞中检测到了BID和BAX的表达。然后，我们使用小干扰RNA（siRNA）抑制KGN细胞中BID和BAX mRNA的表达。当BID或BAX被抑制时，凋亡细胞率显著降低。在颗粒细胞来源的细胞中，BID和BAX显示出促凋亡活性。这些结果表明，BID和BAX在依赖线粒体的II型凋亡中作为信号转导因子发挥作用。
