Apoptosis And Expression Of Apoptosis Genes During Mouse Early Embryonic Development

During the preimplantation embryo development, we can find many abnormal cells especially in the process of in vitro culture. Apoptosis is an important way to eliminate exceptional cells in tissue. Many research show that apoptosis also work in preimplantation embryo. Apoptosis is prevalent in preimplantation embryos; even the embryo is morphological normal. Apoptosis is the result of apoptosis genes expression. The large ratio of apoptosis in embryo may influence the embryo's livability, in order to improve the livability of embryos, which cultured in vitro, many researchers try to inhibit apoptosis in embryos by changing the culture environment, such as additional growth factors.There are many reports about growth factors can influence the development of embryo, but most of them focus on the statistics of the ratio of fetation, the investigation on the mechanism of how these factors work are rare. There is great meaning to explore the mechanism of early embryo development by investigate the apoptosis gene express change during preimplantation embryo development.We use the comet assay, ameliorative project on getting total RNA from embryos combine the nested RT-PCR, immunochemistry,to analysis apoptosis and the change of Bcl-2 family genes expression. Based on these, we examine the influence of IGF-1 on apoptosis and the change of Bcl-2 family genes(Bax,Bcl-2,Bak,Bcl-xl) expression in vitro to investigate the molecular mechanism of IGF-1 influence the development of preimplantation embryos.The results as followed:1. Among the internal studies we take the lead of using the comet assay to examine apoptosis in preimplantation embryo development. The result shows that Apoptosis is prevalent in preimplantation embryos, apoptosis exists in good modality embryos of different stages.2. Using the nested PCR to examine four genes of the Bcl-2 family, we used the ameliorative project to isolate total RNA from embryo cells. In this project, the quantity of embryo is small. We found four of the Bcl-2 family genes prevalent expression during the early embryo development, and change with the different stages.3. The in vitro system without serum upgrades the ratio of apoptosis in embryo. During the stage of morula, Bax express upgrade, while Bcl-2 decrease.4. We found that 100ng/ml IGF-1 can improve the embryo development and the ratio of blastocyst, decrease apoptosis.