Apop-1, a novel protein inducing cyclophilin D-dependent but Bax/Bak-related channel-independent apoptosis

作者:Yasuda Osamu; Fukuo Keisuke; Sun Xin; Nishitani Masahito; Yotsui Takamori; Higuchi Masayoshi; Suzuki Takashi; Rakugi Hiromi; Smithies Oliver; Maeda Nobuyo; Ogihara Toshio
来源:Journal of Biological Chemistry, 2006, 281(33): 23899-23907.
DOI:10.1074/jbc.M512610200

摘要

In the intrinsic pathway of apoptosis, mitochondria play a crucial role by releasing cytochrome c from the intermembrane space into the cytoplasm. Cytochrome c release through Bax/Bak-dependent channels in mitochondria has been well documented. In contrast, cyclophilin D ( CypD), an important component of permeability transition pore-dependent protein release, remains largely undefined, and no apoptogenic proteins that act specifically in a CypD-dependent manner have been reported to date. Here, we describe a novel and evolutionarily conserved protein, apoptogenic protein ( Apop). Mouse Apop-1 expression induces apoptotic death by releasing cytochrome c from mitochondria into the cytosolic space followed by activation of caspase-9 and -3. Apop-1-induced apoptosis is not blocked by Bcl-2 or Bcl-x(L), inhibitors of Bax/Bak-dependent channels, whereas it is completely blocked by cyclosporin A, an inhibitor of permeability transition pore. Cells lacking CypD were resistant to Apop-induced apoptosis. Moreover, inhibition of Apop expression prevented the cell death induced by apoptosis-inducing substances. Our findings, thus, indicate that the expression of Apop-1 induces apoptosis though CypD-dependent pathway and that Apop-1 plays roles in cell death under physiological conditions.

  • 出版日期2006-8-18