用曲细精管微注射法建立绿色荧光蛋白转基因小鼠

目的 研究曲线精管微注射法建立转基因小鼠的可行性。方法 选取人巨细胞病毒启动子调控的增强型绿色荧光蛋白（pCMV－EGFP）表达载体，应用体视解剖镜和显微注射仪将不同剂量的被脂质体包裹的质料DNA注射到不同年龄的KM小鼠曲细精管内。在注射后40d左右，雄鼠与雌鼠合笼交配；分娩后3周，剪取仔鼠尾，提取基因组DNA，应用PCR、Southern blotting技术进行整合检测。处死2只首建小鼠，荧光显微镜观察组织冰冻切片中EGFP的表达。结果 共注射41只雄性小鼠，存活34只，其中32只具有交配、受精能力，获得仔鼠382只。仔鼠经检测，PCR阳性133只，织冰冻切片中EGFP明显表达。结论 曲细精管微注射法是动物基因转移的一条简便可行的新途径。

Construction of transgenic mice carrying enhanced green fluorescent protein gene by seminiferous tubule microinjection.]

OBJECTIVE: To study the feasibility of establishing transgenic mice carrying enhanced green flourescent protein (EGFP) gene by means of seminiferous tubule microinjection. METHODS: The vector expressing enhanced green fluorescent protein under the control of human cytomegalovirus immediate-early promoter (pCMV-EGFP) was selected and mixed with liposome in vitro. Microinjection at different doses of the liposome-entrapped plasmid DNA into the seminiferous tubules of male mice at different ages was performed to establish transgenic mice, which were made to mate with female mice at least 40 d after the microinjection. Genomic DNA was extracted from the offspring of the founder mice for PCR and Southern blotting analysis, and the frozen sections of different tissues from 2 of the founders mice were prepared for fluorescence microscopic observation. RESULTS: Among the 41 mice receiving the microinjection, 32 survived and retained their mating ability and fertility, and among their 382 offspring 133 were positive for EGFP DNA as demonstrated by PCR, 15 of which were confirmed by Southern blotting analysis. The age of the mice or the doses of microinjection they received was not shown to impact the integration of EGFP gene, and fluorescence microscopy failed to detect significant EGFP expression in the tissues of the founder mice (P>0.05) in comparison with normal mice. CONCLUSION: Seminiferous tubule microinjection is simple and practicable to implement gene transfer in mice.