Sakamaki K, Tsukumo S, Yonehara S
Department of Viral Oncology, Institute for Virus Research, Kyoto University, Japan.
Eur J Biochem. 1998 Apr 15;253(2):399-405. doi: 10.1046/j.1432-1327.1998.2530399.x.
Fas (APO-1/CD95) is a transmembrane receptor protein which induces apoptosis upon activation. In apoptosis triggered by Fas, a subset of cysteine proteases designated caspases is activated, playing a central role as effector molecules. Among these caspases, human caspase-8 (FLICE/MACH/Mch5) has been isolated and shown to be indispensable for Fas-mediated apoptotic signaling. In this study, we isolated the mouse homologue to human caspase-8 from a BaF3 cell cDNA library. This molecule conserved the death effector domain (DED) and protease domain as detected in human caspase-8, and was capable of inducing apoptosis in KB and Rat-1 cells when overexpressed. Expression of caspase-8 was detected in the various tissues of adult mouse and in embryos at 9.5 days and 17.5 days of development by Northern-blot analysis. Further, we isolated a chromosomal gene for caspase-8 from a mouse genomic library and analyzed the genomic structure of the isolated gene. This gene consisted of eight exons and seven introns spanning about 26 kb in the coding region.
Fas（APO-1/CD95）是一种跨膜受体蛋白，激活后可诱导细胞凋亡。在Fas触发的细胞凋亡中，一类名为半胱天冬酶的半胱氨酸蛋白酶被激活，作为效应分子发挥核心作用。在这些半胱天冬酶中，人半胱天冬酶-8（FLICE/MACH/Mch5）已被分离出来，并被证明对Fas介导的凋亡信号传导不可或缺。在本研究中，我们从BaF3细胞cDNA文库中分离出了人半胱天冬酶-8的小鼠同源物。该分子保留了在人半胱天冬酶-8中检测到的死亡效应结构域（DED）和蛋白酶结构域，过表达时能够在KB和大鼠-1细胞中诱导细胞凋亡。通过Northern印迹分析在成年小鼠的各种组织以及发育9.5天和17.5天的胚胎中检测到了半胱天冬酶-8的表达。此外，我们从小鼠基因组文库中分离出了半胱天冬酶-8的染色体基因，并分析了分离基因的基因组结构。该基因由八个外显子和七个内含子组成，编码区跨度约为26 kb。
