钙蛋白酶抑制蛋白转基因小鼠的构建和鉴定

目的 将人的钙蛋白酶抑制蛋白（calpastatin，CAST）外源基因整合到C57BL/6J小鼠中，构建高表达CAST的转基因小鼠模型。方法 利用Gateway技术构建pRP.EX3d-EF1A-CAST-IRES-eGFP载体，回收片段后通过显微注射法将目的基因片段注入到C57BL/6J小鼠受精卵中，将其胚胎移植至同期发情的假孕受体母鼠输卵管内获得子代小鼠。采用PCR方法鉴定出阳性的转基因小鼠，确定首建鼠，通过与C57BL/6J小鼠回交后互交数代建系。利用RT-PCR和Western blotting方法检测CAST基因和蛋白在各组织中的表达情况。结果 将90枚注射受精卵移植到3只假孕鼠中，3只均怀孕，移植成功率100%，产下23只子鼠，经PCR鉴定得到2只转基因阳性首建鼠，阳性率为9%。子代小鼠进行RT-PCR检查显示，CAST基因在转基因小鼠的心、肝、脾、肺、肾、脑和骨骼肌中均有表达；Western blotting检查显示，CAST蛋白表达在转基因小鼠中显著高于同窝阴性小鼠。结论 通过显微注射法成功构建CAST高表达的转基因小鼠，为进一步研究CAST奠定了良好的模型基础。

Establishment and identification of calpastatin transgenic mouse models

Objective To establish an animal model of calpastatin (CAST) transgenic mice by inserting the full human CAST into the genome of C57BL/6J mice. Methods Recombinant transgenic vector pRP.EX3d-EF1A-CAST-IRES-eGFP was constructed by Gateway technology. It was injected into the fertilized eggs from C57BL/6J mice. The injected eggs were transplanted into the oviduct of pseudopregnant mice. Tail DNA PCR screening was performed to identify the positive founder mice. The expressions of CAST mRNA and protein in tissues of the transgenic mice were detected by RT-PCR and Western blotting. Results Ninty eggs were transplanted into the oviducts of 3 recipients. The transplantation success rate was 100%. 23 viable offsprings were born from the recipients. Tail DNA PCR screening showed that two of the offsprings were positive transgenic mice. The positive rate of transgenic mice was 9%. RT-PCR assay revealed that CAST mRNA expressions were present in the heart, liver, kidney, lung, spleen, brain and skeletal muscle of the transgenic mice. Additionally, the CAST protein expression was significantly increased in the transgenic mice. Conclusion CAST transgenic mice have been successfully established and provide a good animal model support for further studies on the CAST function.