摘要
By using the approach of immunofluorescence staining with an antibody against 5-methylcytosine (5MeC), the present study detected the DNA methylation patterns of bovine zygotes and preimplanta-tion embryos derived from oocyte in vitro maturation (IVM), in vitro fertilization (IVF) and embryo in vitro culture (IVC). The results showed that: a) paternal-specific demethylation occurred in 61.5% of the examined zygotes, while 34.6% of them showed no demethylation; b) decreased methylation level was observed after the 8-cell stage and persisted through the morula stage, however methylation levels were different between blastomeres within the same embryos; c) at the blastocyst stage, the methyla-tion level was very low in inner cell mass, but high in trophectoderm cells. The present study suggests, at least partly, that IVM/IVF/IVC may have effects on DNA methylation reprogramming of bovine zygotes and early embryos.
By using the approach of immunofluorescence staining with an antibody against 5-methylcytosine (5MeC), the present study detected the DNA methylation patterns of bovine zygotes and preimplanta-tion embryos derived from oocyte in vitro maturation (IVM), in vitro fertilization (IVF) and embryo in vitro culture (IVC). The results showed that: a) paternal-specific demethylation occurred in 61.5% of the examined zygotes, while 34.6% of them showed no demethylation; b) decreased methylation level was observed after the 8-cell stage and persisted through the morula stage, however methylation levels were different between blastomeres within the same embryos; c) at the blastocyst stage, the methyla-tion level was very low in inner cell mass, but high in trophectoderm cells. The present study suggests, at least partly, that IVM/IVF/IVC may have effects on DNA methylation reprogramming of bovine zygotes and early embryos.
基金
the National Natural Science Foundation of China (Grant No. 30270956)
High-Tech Research & Development Program of China (Grant No. 2002AA206311)