Granzyme B activates procaspase-3 which signals a mitochondrial amplification loop for maximal apoptosis.
Granzyme B activates procaspase-3 which signals a mitochondrial amplification loop for maximal apoptosis.
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DOI：
10.1083/jcb.200210158
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发表时间：
2003-03-17
期刊：
影响因子：
--
通讯作者：
Froelich CJ
中科院分区：
文献类型：
--
作者：
Metkar SS;Wang B;Ebbs ML;Kim JH;Lee YJ;Raja SM;Froelich CJ
颗粒酶B（GrB）的作用类似于顶端半胱天冬酶，在穿孔素的细胞内递送后有效地激活蛋白水解级联。这里的研究旨在了解是否生理效应，GrB-丝甘肽，启动凋亡主要通过caspase-3或通过BH 3-唯一的蛋白质与随后的线粒体透化和凋亡。使用四个单独的细胞系，这些细胞系在遗传上缺乏酶原或缺乏活性半胱天冬酶-3，我们测量了全细胞内的凋亡指数（活性半胱天冬酶-3，线粒体去极化[Δ Δ Km]和TUNEL）。遵循这些条件，在GrB递送后在靶中观察到以下情况：（a）半胱天冬酶原-3缺陷型细胞不能显示出降低的Δ Tm和DNA片段化;（B）Bax/巴克是最佳Δ Tm降低、半胱天冬酶-3活化和DNA片段化所需的，而BID切割未被免疫印迹检测到;（c）Bcl-2抑制GrB介导的细胞凋亡通过阻断caspase-3的寡聚化（降低Δ Δ Tm和TUNEL反应性）;和（d）在半胱氨酸天冬氨酸蛋白酶原-3缺陷细胞中，鉴定了一种不依赖于细胞的途径，其涉及半胱氨酸天冬氨酸蛋白酶原-7活化、PARP裂解和核浓缩。因此，这些数据支持存在由GrB启动的完全实施的凋亡途径，由半胱天冬酶-3传播，并通过线粒体扩增环延续，但也强调存在辅助半胱天冬酶依赖性，非依赖性途径。
Granzyme B (GrB), acting similar to an apical caspase, efficiently activates a proteolytic cascade after intracellular delivery by perforin. Studies here were designed to learn whether the physiologic effector, GrB–serglycin, initiates apoptosis primarily through caspase-3 or through BH3-only proteins with subsequent mitochondrial permeabilization and apoptosis. Using four separate cell lines that were either genetically lacking the zymogen or rendered deficient in active caspase-3, we measured apoptotic indices within whole cells (active caspase-3, mitochondrial depolarization [ΔΨm] and TUNEL). Adhering to these conditions, the following were observed in targets after GrB delivery: (a) procaspase-3–deficient cells fail to display a reduced ΔΨm and DNA fragmentation; (b) Bax/Bak is required for optimal ΔΨm reduction, caspase-3 activation, and DNA fragmentation, whereas BID cleavage is undetected by immunoblot; (c) Bcl-2 inhibits GrB-mediated apoptosis (reduced ΔΨm and TUNEL reactivity) by blocking oligomerization of caspase-3; and (d) in procaspase-3–deficient cells a mitochondrial-independent pathway was identified which involved procaspase-7 activation, PARP cleavage, and nuclear condensation. The data therefore support the existence of a fully implemented apoptotic pathway initiated by GrB, propagated by caspase-3, and perpetuated by a mitochondrial amplification loop but also emphasize the presence of an ancillary caspase-dependent, mitochondria-independent pathway.
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DOI：
10.1084/jem.189.1.131
发表时间：
1999-01-04
期刊：
The Journal of experimental medicine
影响因子：
--
作者：
MacDonald G;Shi L;Vande Velde C;Lieberman J;Greenberg AH
通讯作者：
Greenberg AH
颗粒酶B介导的细胞色素C释放受BCL-2家族成员的竞标和BAX的调节。
影响因子：
15.3
作者：
Heibein, J A;Goping, I S;Barry, M;Pinkoski, M J;Shore, G C;Green, D R;Bleackley, R C
通讯作者：
Bleackley, R C
影响因子：
9.2
作者：
Chinnaiyan, AM;Hanna, WL;Dixit, VM
通讯作者：
Dixit, VM
影响因子：
56.9
作者：
Lassus, P;Opitz-Araya, X;Lazebnik, Y
通讯作者：
Lazebnik, Y
影响因子：
4.8
作者：
Guo, Y;Srinivasula, SM;Alnemri, ES
通讯作者：
Alnemri, ES