人的Bcl－X_L和Bcl－X_ScDNA的克隆及表达研究

Cloning and Expression of Bcl0-X_L and Bcl-X_S cDNA

利用一对带有Ｔａｔ在序列的Ｂｃｌ－ｘ专一性引物从ＢＥＡＳ－２Ｂ细胞中扩增出比ｂｃｌ－ＸＬ和ｂｃｌ－ＸｓｃＤＮＡ，并将它们克隆入ｐＧＥＸ－５Ｘ－３载体进行表达。用ＩＰＴＧ诱导表达的融合蛋白占菌体蛋白总量的３０％，经谷胱甘肽－Ｓｅｐｈａｒｏｓｅ亲和层析，蛋白纯度达９０％。这些结果为进一步研究Ｂｃｌ－ｘ在编程性细胞死亡中的作用奠定了基础。

Utilizing tat-contained bcl-x-specific primers designed according to published sequences, bcl-XLand bclxs cDNA were amplifided from transformed human airway epidelial cell line. The cDNA fragments were then cloned into pGEX-5X-3 vector and transformed into E. coli DH5a. The E. coli transformed by recombinant pGEX-5X-3 was induced with IPTG to express fusion proteins. Purified fusion proteins GSTTAT-BCL-Xs and GST-TAT-BCL-XL were got by the method of affinity chromatography.