Pavlok A, Kaláb P, Bobák P
Institute of Animal Physiology and Genetics, Academy of Sciences of the Czech Republic, Libĕchov, Czech Republic.
Zygote. 1997 Aug;5(3):235-46. doi: 10.1017/s0967199400003671.
We have investigated the fertilisation competence, protein synthesis, histone H1 kinase and myelin basic protein (MBP) kinase activities in three categories of bovine oocytes (derived from three size categories of follicles: M--medium, 2.5-5.0 mm; S--small, 1.5-2.5 mm; T--tiny, 1.0-1.5 mm). In contrast to more or less normal meiotic maturation (85.6%) and fertilisation (70.8%) of M oocytes cultured for 24 h, the fertilisation of M oocytes cultured for 40 h was associated with increased rates of retarded male pronuclear development and retention of the second polar body. The S and T oocytes cultured for 24 h or 40 h were mostly arrested at defective late diakinesis-metaphase I (77.5-100%) stage. After fertilisation of S and T oocytes cultured for 24 h no polar body was extruded and formation of one, three or four female pronuclei, together with mostly normal male pronuclei, was observed. The fertilisation of S and T oocytes after 40 h culture resulted in a higher number of female and a decreased number of male pronuclei. A major change in the pattern of protein synthesis was associated with the resumption of meiosis. There were no significant differences in the profile of protein synthesis between oocyte categories in all groups either matured or fertilised. The H1 kinase activity reached comparable increased levels in oocytes of all categories matured for 24 h and decreased during the 40 h culture, most significantly in M oocytes. The MBP kinase activity was at approximately the same high level in all categories of oocytes after 24 h of culture and remained stable until 40 h. The fertilisation after 24 h of culture resulted, in M oocytes, in low levels of both H1 and MBP kinase activities; in S oocytes, only H1 kinase was completely inactivated while MBP kinase activity decreased to some extent; in T oocytes, both H1 and MBP kinase activity decreased. Fertilisation of all oocyte categories after 40 h culture resulted in complete inactivation of both these kinases to their basal levels.
我们研究了三类牛卵母细胞（分别来自三种大小的卵泡：M——中等大小，2.5 - 5.0毫米；S——小，1.5 - 2.5毫米；T——微小，1.0 - 1.5毫米）的受精能力、蛋白质合成、组蛋白H1激酶和髓鞘碱性蛋白（MBP）激酶活性。与培养24小时的M卵母细胞或多或少正常的减数分裂成熟（85.6%）和受精（70.8%）情况不同，培养40小时的M卵母细胞受精后，雄性原核发育延迟和第二极体滞留的发生率增加。培养24小时或40小时的S和T卵母细胞大多停滞在有缺陷的终变期末 - 中期I（77.5 - 100%）阶段。培养24小时的S和T卵母细胞受精后没有排出极体，观察到形成了一个、三个或四个雌性原核，同时雄性原核大多正常。培养40小时后的S和T卵母细胞受精导致雌性原核数量增加，雄性原核数量减少。蛋白质合成模式的一个主要变化与减数分裂的恢复有关。在所有成熟或受精的组中，卵母细胞类别之间的蛋白质合成谱没有显著差异。所有类别培养24小时的卵母细胞中H1激酶活性达到相当的升高水平，并在40小时培养期间下降，在M卵母细胞中最为明显。培养24小时后，所有类别卵母细胞中的MBP激酶活性处于大致相同的高水平，并一直稳定到40小时。培养24小时后受精，在M卵母细胞中，H1和MBP激酶活性均处于低水平；在S卵母细胞中，只有H1激酶完全失活，而MBP激酶活性有一定程度下降；在T卵母细胞中，H1和MBP激酶活性均下降。培养40小时后所有类别卵母细胞受精导致这两种激酶完全失活至基础水平。
