Gdf9,Dnmt1,Zar1,Mater Expression In Ooctyes,Cumulus Cells And Embryos Of Sheep

Oocyte maturation and quality influence fertilization and embryo development directly, and there are some interactions between oocytes and cumulus cells. This thesis studied the mRNA expression of Gdf9,Zar1,Mater,Dnmt1, analyzing by using Real-time PCR, in ovine oocytes, cumulus cells and embryos from different sources, stages or culturing systems in order to investigate the expression patterns of those four genes during ovine oocyte maturation and preimplantation embryonic development, and the relationship between oocyte quality and mRNA levels of Gdf9, Zar1, Mater, Dnmt1. The mRNA levels of Gdf9, Zar1, Mater, Dnmt1 decreased gradually during development of oocytes and embryos(P<0.05). The mRNA of Gdf9 and Zar1 were detected from oocyte to blastula. The mRNA levels of Dnmt1 was lowest in 16-cell stage and not detected in embryos(P<0.05). The mRNA levels of Mater was lowest in 8-cell stage (P<0.05) and the mRNA levels of Gdf9, Zar1, Mater were highest in GV oocytes (P<0.05). The mRNA levels of Dnmt1 were highest in 12 h(P<0.05). Those genes declined gradually from 18 to 24 h(P<0.05), but increase when cultured 30 h in maturation system(P<0.05). The mRNA levels of those four genes were higher in oocytes with the first polarbody than that in oocytes without the first polarbody (P<0.05). The mRNA levels of Gdf9, Zar1, Mater and Dnmt1 were higher in the COCs than in NOs(P<0.05) by detecting mRNA levels in COCs,Naked oocytes(NOs) and different stages of cumulus cells. The mRNA levels of Gdf9, Zar1 and Mater in GV oocytes were significantly higher than those in 24 h mature oocytes(P<0.05). The mRNA levels of Gdf9,Zar1 and Mater in premature cumulus cells were significantly lower than those in mature cumulus cells (P<0.05). In brief, the results indicated that the mRNA levels of Gdf9, Zar1, Mater, Dnmt1 changed during oocyte maturation and preimplantation embryonic development. The expression abundance of those four genes in 24 h mature oocytes was higher in low quality oocytes than that in high quality oocytes. It suggests that those four genes can be judged as molecular markers related to oocyte quality. As some differences of the mRNAs levels in the above mentioned genes were observed between ovine oocytes and cumulus cells, it suggests that the mRNA of those four genes have functions in the celular interactions between oocytes and cumulus cells.