Sathananthan A H, Tatham B, Dharmawardena V, Grills B, Lewis I, Trounson A
Faculty of Health Sciences, La Trobe University, Carlton, Victoria, Australia.
Arch Androl. 1997 Jan-Feb;38(1):37-48. doi: 10.3109/01485019708988530.
Immature cumulus oocyte complexes (COCs) were aspirated from ovarian follicles of slaughtered cow and matured for 24 h in TCM 199 medium with hormones. Eighty-five percent of oocytes matured with subsequent abstriction of the polar body. Matured COCs were then inseminated with frozen-thawed semen (2 x 10(6)/mL final concentration). Eighteen hours after insemination, fertilized COCs were vortexed, washed, and cultured to the pronuclear stage and syngamy (24-36 h postinsemination) and fixed for TEM. Unfixed embryos achieved a cleavage rate of 54%, with 29% developing to blastocysts. Fertilization was confirmed by TEM. Examination of fertilized bipronuclear ova revealed the presence of a sperm aster associated with sperm midpieces, tails, and male pronuclei in several embryos. Further examination of embryos at syngamy showed centrioles at one pole of the first mitotic bipolar spindle in two embryos. Since the mature oocyte at metaphase II has no centrioles at spindly poles, this centriole was most likely derived from the sperm, which has a single proximal centriole associated with pericentriolar material in its neck region, like most mammalian sperm. Tripronuclear ova produced disorganized bipolar spindles or, rarely, tripolar spindles. Bovine embryos, too, follow Boveri's rule of paternal inheritance as in man and most animals. It is possible that both paternal centrosomes (centrioles) and maternal centrosomes are involved in the organization of bipolar spindles in these embryos, quite unlike the mouse embryo where maternal centrosomes seem to organize the first mitotic spindle. The bovine embryo appears to be an appropriate model to study centriolar inheritance.
从未成熟的卵丘卵母细胞复合体（COCs）取自屠宰母牛的卵巢卵泡，并在含有激素的TCM 199培养基中成熟24小时。85%的卵母细胞成熟并随后排出极体。然后将成熟的COCs与冻融精液（最终浓度为2×10⁶/mL）进行授精。授精18小时后，对受精的COCs进行涡旋、洗涤，并培养至原核期和融合期（授精后24 - 36小时），然后固定用于透射电子显微镜（TEM）观察。未固定的胚胎的卵裂率为54%，其中29%发育为囊胚。通过TEM确认受精情况。对受精的双原核卵进行检查发现，在几个胚胎中存在与精子中段、尾部和雄原核相关的精子星体。对处于融合期的胚胎进一步检查发现，在两个胚胎中，第一有丝分裂双极纺锤体的一极存在中心粒。由于处于中期II的成熟卵母细胞在纺锤体极没有中心粒，所以这个中心粒很可能来自精子，就像大多数哺乳动物的精子一样，其颈部区域有一个与中心粒周围物质相关的单个近端中心粒。三原核卵产生紊乱的双极纺锤体，或很少见的三极纺锤体。牛胚胎也像人类和大多数动物一样遵循博韦里的父系遗传规律。这些胚胎中的双极纺锤体的组织可能涉及父本中心体（中心粒）和母本中心体，这与小鼠胚胎不同，在小鼠胚胎中母本中心体似乎组织了第一个有丝分裂纺锤体。牛胚胎似乎是研究中心粒遗传的一个合适模型。
