Expression of the CTCF gene in bovine oocytes and preimplantation embryos

The CCCTC - binding factor (CTCF) is a protein involved in repression, activation, hormone-inducible gene silencing, functional reading of imprinted genes and X-chromosome inactivation. We analyzed CTCF gene expression in bovine peripheral blood, oocytes and in different cellular stages (2-4 cells, 8-16 cells, 16-32 cells, morulae, and blastocysts) of in vitro fertilized embryos. This is the first report of CTCF expression in oocytes and preimplantation bovine embryos and has implications for the production of embryonic stem cells and the development of novel medical technologies for humans.

Spatio-temporal Expression of Heterologous Oct-4 Promoter in Preimplantation Embryos of Pig, Rabbit and Mouse / 生物化学与生物物理进展

The transcription factor Oct-4 is expressed specifically in mammalian preimplantation embryos and its function is related to the maintenance of embryonic stem cell pluripotency. The functional role of the heterogenous expression of Oct-4 remains unclear however. A GFP reporter construct, pOct-4(p)-GFP was generated, containing the upstream regulatory regions of bovine Oct-4 gene and its expression pattern was evaluated in the developing embryos of mouse, pig and rabbit following intracytoplasmic sperm injection. GFP fluorescence was visible early at the 2-cell stage and then became stronger in the blastocysts of all three species. However, the distribution of the GFP signals was restricted to the cells of inner cell mass and no fluorescence was detectable in trophectoderm cells. These results suggest that the bovine Oct-4 promoter is functional and that its embryonic expression activity is similar in different mammalian species.

The expression of seven imprinted genes in human preimplantation embryos / 解放军医学杂志

Objective To perfect gene profile expressed in pre-implantation embryos. Methods Using nested RT-PCR to investigate the expression of seven imprinted genes: P57~ KIP2, LIT1, TSSC3, GRB10, PEG3, ARHI, and ZAC1 in human oocytes and pre-implantation embryos. Results Transcripts of P57~ KIP2 and ZAC1 were detected in human oocytes and at all stages of pre-implantation; LIT1 was expressed only in stages of 8-cell and blastocyst; transcripts of TSSC3 could not be detected; GRB10 mRNA could be detected in oocytes and pre-implantation embryos except for 2-cell embryo; ARHI was expressed in oocytes and 2,8-cell embryos and blastocyst; Peg3 mRNA existed in 4,8-cell embryos and blastocyst. Conclusion Except for TSSC3, transcripts of the other six imprinted genes are detected in human pre-implantation development, which are helpful for pre-implantation diagnosis of imprinted diseases, and provide the theoretical basis for understanding the correlation among assisted reproductive technology, genetic imprinted diseases and tumor.

Effect of Antioxidant on the Toxicity Induced by Cadmium in Preimplantatio Embryos In Vitro / 대한산부인과학회잡지

In order to elucidate the mechanism of oxidative damage of cadimu(Cd) on culturedmouse preimplantation embyors.The embryotoxocity of Cd was examined after cultured mouse preimplantation embryoswere exposed to various concentrations of CdCl2. In addition, the protected effect of antioxidant,catalase against Cd-induced embryotoxicity was investigated.CdCl2 decreased the development of cultured mouse preimplantation embryos in dose andtime-dependent manners, and also oxidative damage was involoved in Cd-induced embryotoxicityin mouse preimplantation embryos by the prevention of catalase on Cd-induced toxicity.

Effect of Antioxidant on the Toxicity Induced by Cadmium in Preimplantatio Embryos In Vitro / 대한산부인과학회잡지

In order to elucidate the mechanism of oxidative damage of cadimu(Cd) on culturedmouse preimplantation embyors.The embryotoxocity of Cd was examined after cultured mouse preimplantation embryoswere exposed to various concentrations of CdCl2. In addition, the protected effect of antioxidant,catalase against Cd-induced embryotoxicity was investigated.CdCl2 decreased the development of cultured mouse preimplantation embryos in dose andtime-dependent manners, and also oxidative damage was involoved in Cd-induced embryotoxicityin mouse preimplantation embryos by the prevention of catalase on Cd-induced toxicity.

THE EFFECT OF PEROXIREDOXIN Ⅱ ON IN VITRO DEVELOPMENT OF MOUSE PREIMPLANTATION EMBRYOS AND ITS MECHANISM / 解剖学报

Objective To study the effect of Peroxiredoxin Ⅱ on development of mouse preimplantation embryos in vitro and to investigate the possible action of Peroxiredoxin Ⅱ on preimplantation embryonic development. Methods One-cell embryos collected from the oviduct of the superovulated mice were cultured in microdrops of medium for 48?h.The effect of peroxiredoxin Ⅱ antibody on the development of embryo in vitro was observed,and the percentage of embryos developing to 2-and 4-cell stage of embryos was used as evaluation criteria.With redox-sensitive fluorescence probe 2′,7′-dichlorodihydroflurescin diacete(DCFH-DA),reactive oxygen species(ROS) induced by Peroxiredoxin Ⅱ antibody was monitored in mouse embryos after 24?h culture by laser confocal scanning microscopy. Results The embryonic development rate from 2-cell stage to 4-cell stage was decreased significantly by Peroxiredoxin Ⅱ antibody in the dilution of 1∶100 and 1∶200,but Peroxiredoxin Ⅱ antibody had no inhibitive effect on development from 1-cell to 2-cell stage.Moreover,Peroxiredoxin Ⅱ antibody in the dilution of 1∶200 induced increase in the production of reactive oxygen species in mouse embryos from 24?h culture of one-cell embryo.Conclusion Peroxiredoxin Ⅱ antibody induced the generation of “2-cell block” by increasing the production of reactive oxygen species(ROS) in mouse embryos.These results also indicated that Peroxiredoxin Ⅱ may reduce or eliminate ROS in preimplantation embryos and promote the development of preimplantation embryos.;