Direct exposure of chromosomes to nonactivated ovum cytoplasm is effective for bovine somatic cell nucleus reprogramming.
We examined the in vitro developmental potential of nonactivated and activated enucleated ova receiving cumulus cells at various stages of the cell cycle. Eleven to 29% of activated ova receiving donor cells stopped developing at the 8-cell stage but 21% to 50% of nonactivated ova receiving donor cells at either the G(0), G(1), G(2), or M phase, or cycling cells developed into blastocysts. One normal calf was born after transferring five blastocysts that had developed from ova receiving donor cells at the M phase. The present study demonstrated that direct exposure of donor chromosomes to nonactivated ovum cytoplasm is effective for somatic cell nucleus reprogramming, and activated ovum cytoplasm does not reprogram the nucleus.
Tani
T
T
Laboratory of Animal Reproduction, College of Agriculture, Kinki University, Nakamachi, Nara, 631-8505, Japan.
Kato
Y
Y
Tsunoda
Y
Y
D000818:Animals; D001755:Blastocyst / Q000502:physiology; D002417:Cattle; D002453:Cell Cycle; D002467:Cell Nucleus / Q000502:physiology*; D002478:Cells, Cultured; D002875:Chromosomes / Q000502:physiology*; D016895:Culture Media, Serum-Free; D003593:Cytoplasm / Q000502:physiology*; D004624:Embryo Transfer; D005260:Female; D005434:Flow Cytometry; D016193:G1 Phase; D016195:G2 Phase; D008938:Mitosis; D053652:Nuclear Transfer Techniques; D010053:Ovary / Q000166:cytology; D010063:Ovum / Q000648:ultrastructure*; D016192:Resting Phase, Cell Cycle; D016196:S Phase
D016895:Culture Media, Serum-Free