FLICE is activated by association with the CD95 death-inducing signaling complex (DISC)
FLICE is activated by association with the CD95 death-inducing signaling complex (DISC)
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DOI：
10.1093/emboj/16.10.2794
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发表时间：
1997-05-15
期刊：
影响因子：
11.4
通讯作者：
Peter, ME
中科院分区：
文献类型：
--
作者：
Medema, JP;Scaffidi, C;Peter, ME
激活后，诱导凋亡的细胞膜受体 CD95 (APO-1/Fas) 将一组细胞内信号蛋白 (CAP1-4) 募集到死亡诱导信号复合物 (DISC) 中，在 DISC 中，CAP1 和 CAP2 代表 FADD/MORT1，CAP4 最近被鉴定为 ICE 样蛋白酶 FLICE，具有两个死亡效应域 (DED)，这里我们表明 FLICE 结合 通过其 N 端 DED 至 FADD，这是在所有测试的 CD95 敏感细胞的 DISC 中检测到的 CD95 信号传导中的一个必要步骤，在用激动性抗体长时间触发 CD95 时，所有胞质 FLICE 都会被蛋白水解激活，生理 FLICE 裂解需要与 DISC 关联并通过两步机制发生，初始裂解生成 p43 和 p43 p12 片段进一步加工成 p10 片段，随后切割受体结合的 p43 导致形成前结构域 p26 并释放包含活性位点的片段 p18。FLICE 的激活被肽抑制剂 zVAD-fmk、zDEVD-fmk 和 zIETD-fmk 阻断，但不能被 crmA 或 Ac-YVAD-CHO 阻断。综上所述，我们的数据表明 FLICE 是 CD95 激活的一系列 ICE 样蛋白酶中的第一个，并且这种激活需要功能性 CD95 DISC。
Upon activation, the apoptosis-inducing cell membrane receptor CD95 (APO-1/Fas) recruits a set of intracellular signaling proteins (CAP1-4) into a death-inducing signaling complex (DISC), In the DISC, CAP1 and CAP2 represent FADD/MORT1, CAP4 was identified recently as an ICE-like protease, FLICE, with two death effector domains (DED), Here we show that FLICE binds to FADD through its N-terminal DED, This is an obligatory step in CD95 signaling detected in the DISC of all CD95-sensitive cells tested, Upon prolonged triggering of CD95 with agonistic antibodies all cytosolic FLICE gets proteolytically activated, Physiological FLICE cleavage requires association,vith the DISC and occurs by a two-step mechanism, Initial cleavage generates a p43 and a p12 fragment further processed to a p10 fragment, Subsequent cleavage of the receptor-bound p43 results in formation of the prodomain p26 and the release of the active site-containing fragment p18, Activation of FLICE is blocked by the peptide inhibitors zVAD-fmk, zDEVD-fmk and zIETD-fmk, but not by crmA or Ac-YVAD-CHO. Taken together, our data indicate that FLICE is the first in a cascade of ICE-like proteases activated by CD95 and that this activation requires a functional CD95 DISC.