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

为了评估骨桥蛋白的作用，我们准备在小鼠系统中检测骨桥蛋白过表达和骨桥蛋白基因失活的影响。我们首次克隆了小鼠骨桥蛋白基因，并利用其上游外显子构建了表达载体。这些构建物还含有新基因盒，并通过电穿孔将其导入小鼠ES细胞。选择含有骨桥蛋白基因同源重组的ES细胞，将其导入胚泡。用毛色鉴定乳糜鼠，并与骨桥蛋白基因缺失的小鼠进行同源重组。在过表达实验中，将骨桥蛋白基因克隆到强启动子下游，形成诱导型表达载体，并通过显微注射将其导入受精卵，然后植入假孕小鼠子宫内。

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.