Transgenic analysis of the expression of OPN gene-encoding a molecule responsible for cancer cell attachment.

为了阐明骨桥蛋白的作用，我们准备在小鼠系统中研究骨桥蛋白过表达和骨桥蛋白基因失活对骨桥蛋白的影响。我们首先克隆了小鼠骨桥蛋白基因，并利用上游外显子构建了载体。这些构建体还含有新基因盒，并通过电穿孔法导入小鼠胚胎干细胞。选择骨桥蛋白基因同源重组的胚胎干细胞，将其导入囊胚。通过毛色鉴定嵌合小鼠，并通过同源重组与骨桥蛋白基因缺失小鼠配对。在过表达实验方面，我们将骨桥蛋白基因从一个强启动子顺流克隆得到可诱导表达载体，并将该载体微量注射到受精卵中，植入假孕小鼠子宫。

To eluidate the role of osteopontinm, we prepared to examine the effect of osteopontin overexpression as well as inactivation of osteopontin gene in mice system. We first cloned murine osteopontin gene and constructed vectors by using the upstream exons. These constructs also contained neo-gene cassett and were introduced into murine ES cells by electroporation. ES cells containing homologous recombination in the osteopontin gene were selected and they were introduced into the blastocele. Chymeric mice were identified by their coat color and were mated to prodece mice which lack osteopontin gene through homolo gous recombination. With regard to over expression experiments, osteopontin gene was cloned down stream of a strong promoter to yield inducible expression vectors and this vector was introduced via microinjection into fertilized eggs which were subsequently implanted into the uterus of pseudo-pregnant mice.