earticle

영어

Heterozygous status of recipient mitochondria and donor mitochondria in somatic cell nuclear transfer (SCNT) embryo is a quite defective. To solve the problem, our previous research has proposed that treatment of 2’,3’-dideoxycytidine (ddC) for in vitro maturation of oocyte induces the depletion of mtDNA in bovine oocytes. Bovine oocytes were matured in 20 μM ddC for 24h at 39℃ in a humidified atmosphere of 5% CO2. The second meiotic metaphase (MⅡ) oocytes were selected for oocyte activation and then activated by a combination of 5 μM inomycin for 5 min and 2 mM 6-DMAP for 3 h. GFP-tagged exogenous mitochondria were injected into the parthenogentic embryos using a 15 μM of injection pipette at 16 h after oocyte activation. Embryos were cultured in mSOFaa medium and changed medium every 2 days. At 7 days, the development rate of embyos was measured. GFP and hoechest were observed by a fluorescence microscope. As a result, the maturation rate of bovine oocytes were not significantly lower than that in the control oocyte. In addition, the development of embryos treated with 20 mM ddC for in vitro maturation and injected exogenous mitochondria was not different from that of the control. However, expression of GFP was showed only in the embryos injected exogenous mitochondria. In conclusion, we transmitted exogenous mitochondria into mtDNA depleted bovine oocytes.