家蚕凋亡相关基因ice的克隆及在大肠杆菌中的表达

Cloning of interlukin-1 β-converting enzyme (ICE) apoptosis-related genes from Bombyx mori and its expression in Escherichia coli

ICE(白细胞介素-1β转换酶)是caspase家族(半胱氨酸天门冬氨酸蛋白酶cys-teinylaspartate specific proteinase)中最早发现的成员,在多细胞生物细胞凋亡的过程中起着重要作用。为了深入了解模式昆虫家蚕ICE在凋亡通路中的作用,采用紫外线刺激家蚕细胞,PCR克隆获得2个新的ice基因不同剪切体,分别命名为ice-2和ice-5(GenBank登录号:DQ360829和DQ360830),并将这2个剪切体分别克隆进原核表达载体pET28a中,在大肠杆菌中诱导表达,对表达产物进行了检测,结果显示ICE-2和ICE-5蛋白表达过程中能发生自我剪切。

ICE （ interlukin-1 β-converting enzyme ）, the first member of caspases （ cys-teinylaspartate specific proteinase） ,plays an important role in executing of programmed cell death in multicellular organisms. In order to obtain more information about ICE of the model insect-silkworm on apoptosis pathways, ultraviolet radiation was used to stimulate silkworm cells. The total RNA of the stimulated cells was extracted and two novel isoforms of ice family were obtained by RT-PCR. They were named as ice-2 and ice-5 （ GenBank accession numbers ： DQ360829 and DQ360830）. The cDNA fragments of ice-2 and ice-5 were inserted into expression vector of pET28a. The expression of ice-2 and ice-5 in E. coli strain DE3 was induced at 37℃ and 25℃ ,respectively. The results showed that both the products of ice-2 and ice-5 can be modified after protein expression.