小鼠β-酪蛋白基因序列调控人-tPA突变体基因在小鼠乳腺的表达  

Murine β-casein Gene Sequences Direct a Human Tissue Plasminogen Activator Variant Expressed in the Milk of Transgenic Mice

作　　者：林福玉[1] 程萱[1] 陈红星[1] 谭晓红[1] 程竞[1] 杨晓[1] 邓继先[1] 黄培堂[1] 

机构地区：[1]军事医学科学院生物工程研究所,北京100071

出　　处：《Acta Genetica Sinica》2002年第12期1057-1062,共6页

基　　金：国家"8 63"高技术发展计划基金 (2 0 0 1AA2 13 0 3 1)资助课题~~

摘　　要：为验证克隆的小鼠 β -酪蛋白基因序列调控外源基因表达的能力 ,将人t PA突变体基因的信号肽 -前肽编码序列用小鼠 β -酪蛋白的信号肽编码序列替换 ,人t PA突变体成熟肽cDNA融合到小鼠 β -酪蛋白基因的第 2外显子中 ,从而构建成旨在应用小鼠 β -酪蛋白基因序列调控人t PA突变体基因在小鼠乳腺中表达的载体。融合基因经显微注射至小鼠的受精卵中 ,2 85枚注射的受精卵移植到 13只受体小鼠。经PCR和Southern杂交鉴定 ,4 2只出生小鼠中有 12只为转基因阳性鼠。 7只转基因阳性鼠乳汁中表达人t PA突变体 ,最高表达水平为 3.6 5 93μg/ml,证明小鼠 β-酪蛋白基因序列能够调控人t PA突变体基因在转基因小鼠的乳汁中表达出具有生物活性的人t PA突变体 ,为进一步制备人t PA突变体基因敲入小鼠模型提供了理论和实验依据。To investigate the ability of our cloned murine β casein locus to direct the exogenous gene expression in the milk of transgenic mice,the human t PA variant mammary gland expression vector under the control of murine β casein gene regulatory elements was constructed,in which the human t PA variant signal pro peptide sequence was replaced with murine β casein signal peptide sequence and the human t PA variant mature peptide cDNA was inserted into the second exon of β casein gene. The fusion gene was microinjected in the fertilized mice eggs. A total of 285 embryos were microinjected and transferred into 13 surrogate mother mice. Twelve positive transgenic mice were identified through PCR and Southern blot analysis among 42 new born mice. Human t PA variant was expressed in the milk of 7 transgenic mice,the highest expression level attained to 3.6593 μ g/ml. The results demonstrated that the murine β casein gene regulatory elements can direct the human t PA variant gene successfully express in the milk of transgenic mice. It lays great foundation for the research on the β casein knock in mice mammary gland bioreactor model construction.

关 键 词：小鼠 Β-酪蛋白 基因序列 调控 人t-PA 突变体基因 乳腺 表达 组织型结溶酶原激活剂 

分 类 号：Q786[生物学—分子生物学]