Kim Bong-Ki, Cheon Sun Hong, Lee Youn Jeong, Choi Sun Ho, Cui Xiang Shun, Kim Nam-Hyung
Department of Animal Science, Chungbuk National University, Cheong Ju, Chungbuk 361-763, Korea.
Zygote. 2003 Aug;11(3):261-70. doi: 10.1017/s0967199403002314.
The onset of pronucleus formation and DNA synthesis in porcine oocytes following the injection of porcine or murine sperm was determined in order to obtain insights into species-specific paternal factors that contribute to fertilisation. Similar frequencies of oocytes with female pronuclei were observed after injection with porcine sperm or with murine sperm. In contrast, male pronuclei formed 8-9 h following the injection of porcine sperm, and 6-8 h following the injection of murine sperm. After pronucleus formation maternally derived microtubules were assembled and appeared to move both male and female pronuclei to the oocyte centre. A few porcine oocytes entered metaphase 22 h after the injection of murine sperm, but normal cell division was not observed. The mean time of onset of S-phase in male pronuclei was 9.7 h following porcine sperm injection and 7.4 h following mouse sperm injection. Ultrastructural observation revealed that male pronuclei derived from murine sperm in porcine oocytes are morphologically similar to normal male pronuclei in porcine zygotes. These results suggest that species-specific paternal factors influence the onset of pronucleus formation and DNA synthesis. However, normal nuclear cytoplasmic interactions were observed in porcine S-phase oocytes following murine sperm injection.
为了深入了解有助于受精的物种特异性父本因素，对注射猪精子或鼠精子后的猪卵母细胞原核形成和DNA合成的起始情况进行了测定。注射猪精子或鼠精子后，观察到形成雌原核的卵母细胞频率相似。相比之下，注射猪精子后8-9小时形成雄原核，注射鼠精子后6-8小时形成雄原核。原核形成后，母源微管组装并似乎将雄原核和雌原核都移至卵母细胞中心。注射鼠精子22小时后，少数猪卵母细胞进入中期，但未观察到正常的细胞分裂。注射猪精子后，雄原核中S期开始的平均时间为9.7小时，注射小鼠精子后为7.4小时。超微结构观察显示，猪卵母细胞中源自鼠精子的雄原核在形态上与猪受精卵中的正常雄原核相似。这些结果表明，物种特异性父本因素影响原核形成和DNA合成的起始。然而，注射鼠精子后的猪S期卵母细胞中观察到了正常的核质相互作用。
