目的:建立性激素结合球蛋白(SHBG)基因条件敲除小鼠模型,为探讨胎盘组织中SHBG在体内的生理功能及其与妊娠期糖尿病发病关系提供实验手段。方法:首先运用生物信息学手段确定小鼠SHBG基因组序列,构建SHBG打靶载体,以电穿孔方法将其导入小鼠ES细胞,筛选培养阳性ES细胞并行PCR鉴定,并将正确同源重组的ES细胞注射进小鼠囊胚,移入受体小鼠子宫;将获得的嵌合体小鼠与C57BL/6J小鼠交配,筛选后获得Flox小鼠,该小鼠与EIIa-Cre转基因小鼠杂交,子代多次自交获得SHBG全身基因敲除(SHBG~(-/-))的小鼠。结果:运用同源重组及ES细胞技术建立了SHBG基因的Flox小鼠,并利用Cre/Loxp重组酶系统建立了SHBG基因全身敲除小鼠模型,PCR方法从基因水平证明了SHBG基因Flox小鼠及SHBG基因全身敲除小鼠模型建立成功。对基因敲除鼠进行初步表型分析发现:SHBG基因全身敲除小鼠的生长发育与野生型小鼠相比无明显肉眼所见异常,SHBG基因全身敲除雌雄小鼠均具有生殖能力。结论:成功建立SHBG基因全身敲除小鼠模型,通过对基因敲除鼠进行初步表型分析,发现SHBG基因全身敲除小鼠外观上发育正常,为进一步研究SHBG在妊娠期糖尿病中的作用奠定了基础。
Objective: To generate sex hormone binding globulin( SHBG) conditional knockout mice model.In order to investigate the physiological function of SHBG in vivo and to provide experimental means for the study of the relationship between SHBG and gestational diabetes mellitus. Methods: The mouse genomic DNA sequence of SHBG was verified through bioinformatic analysis. According to the SHBG genomic DNA sequence,the gene targeting and knockout vector were constructed. Transfection of the vectors to ES cells by electroporation was performed according to common protocol. Positive ES cells were screened and identified by PCR. Therefore,the dual selected ES cells were microinjected into blastula,then blastula transplantations into the host mice. The chimeric mice were mated with C57BL/6J mice,and the Flox mice were obtained after screening. The Flox mice were hybridized with EIIA-Cre transgenic mice,and the progeny of the SHBG gene knockout( SHBG~(-/-)) mice were obtained by autocopuation for several times. Results: Several Flox homozygous mice and SHBG gene knockout mice were successfully obtained. Compared with control mice,homozygous mice of SHBG gene knockout were well developed and had reproductive ability. The growth and development of SHBG knockout mice were not significantly different from that of wild type mice. Conclusion: Homozygous mice model of SHBG gene knockout was successfully established,which laid the foundation for further study of the role of SHBG in the gestational diabetes. The SHBG gene knockout mouse model was successfully established and the preliminary phenotypic analysis was performed,which laid the foundation for further study on the role of SHBG in gestational diabetes mellitus. SHBG gene knockout mice were normal in appearance. Due to the limited number of samples and many unknown biological characteristics of gene knockout mice,it needs further study.