Takeda S, Toyoda Y
Department of Animal Pathology, University of Tokyo, Japan.
Mol Reprod Dev. 1991 Oct;30(2):90-4. doi: 10.1002/mrd.1080300203.
In order to study the expression of an exogenous gene in developing mouse embryos during the preimplantation period, DNA carrying the SV40 early promoter fused with the Escherichia coli beta-galactosidase gene (lacZ) was microinjected into the pronucleus of fertilized mouse eggs. Expression of lacZ gene was detected by staining embryos with 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside (X-gal) as a substrate at pH 7.2. The embryos expressing the lacZ gene showed various intensities of blue staining, all showing a mosaic pattern. The exogenous gene was expressed from the 4-cell stage until the blastocyst stage. The proportion of embryos expressing the lacZ gene was maximal (38%) at the morula stage, and the expression was dependent on the presence of the SV40 promoter.
为了研究植入前阶段发育中的小鼠胚胎中外源基因的表达情况，将携带与大肠杆菌β-半乳糖苷酶基因（lacZ）融合的SV40早期启动子的DNA显微注射到受精小鼠卵的原核中。以5-溴-4-氯-3-吲哚基-β-D-吡喃半乳糖苷（X-gal）为底物，在pH 7.2条件下对胚胎进行染色，检测lacZ基因的表达。表达lacZ基因的胚胎呈现出不同强度的蓝色染色，均表现为镶嵌模式。外源基因从4细胞阶段一直表达至囊胚阶段。在桑椹胚阶段，表达lacZ基因的胚胎比例最高（38%），且该表达依赖于SV40启动子的存在。
