Degradation of pig cyclin B1 molecules precedes MAP kinase dephosphorylation during fertilisation of the oocytes
Degradation of pig cyclin B1 molecules precedes MAP kinase dephosphorylation during fertilisation of the oocytes
复制标题
卵母细胞受精过程中猪细胞周期蛋白 B1 分子的降解先于 MAP 激酶去磷酸化
DOI：
10.1017/s0967199400000939
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发表时间：
2000
期刊：
影响因子：
1.7
通讯作者：
R. Moor
中科院分区：
文献类型：
--
作者：
T. Miyano;Y. Dai;J. Lee;K. Kano;R. Moor
猪卵母细胞在中期II激活精子在环己酰亚胺自由和含环己酰亚胺受精培养基的渗透。受精后，精确的核阶段，细胞周期蛋白B1的降解和MAP激酶的去磷酸化的动力学进行了评估。成熟培养后，96%的卵母细胞达到中期II。授精后6小时，在无环己酰亚胺培养基中，68%的卵母细胞被激活，并已进展到后期II或更高。8小时后，89%的卵母细胞被激活：一个女性原核已经形成，穿透精子的头部已经扩大，并改变为男性原核。在含环己酰亚胺的培养基中，卵母细胞的激活开始早于无环己酰亚胺的培养基。4 h后，43%的卵母细胞被激活，6 h后激活率上升到97%。猪细胞周期蛋白B1消失在受精后6小时，在两个环己酰亚胺含和环己酰亚胺的媒体。猪卵母细胞在中期II含有两种类型的MAP激酶- ERK 1和ERK 2 -在其活性磷酸化形式。授精后8 h，在含环己酰亚胺和不含环己酰亚胺的培养基中培养的卵母细胞中，ERK 2变为快速迁移的无活性形式，尽管向下移动不完全。这种变化在细胞周期蛋白B1分子降解后延迟2 h。这些结果表明，猪细胞周期蛋白B1分子的降解对应于卵母细胞从中期II停滞到后期II/末期II的过渡，然后是MAP激酶去磷酸化。
Pig oocytes at metaphase II were activated by penetration of spermatozoa in cycloheximide-free and cycloheximide-containing fertilisation media. The precise nuclear stage, and the kinetics of degradation of cyclin B1 and dephosphorylation of MAP kinase were assessed after insemination. After maturation culture, 96% of oocytes reached metaphase II. At 6 h after insemination in cycloheximide-free medium, 68% of the oocytes were activated and had progressed to anaphase II or beyond. After 8 h, 89% of the oocytes were activated: a female pronucleus had formed and the heads of penetrating spermatozoa had enlarged and changed to male pronuclei. In the cycloheximide-containing medium, activation of oocytes started earlier than in cycloheximide-free medium. After 4 h, 43% of the oocytes were activated, and the percentage increased to 97% after 6 h. Pig cyclin B1 disappeared in the oocytes at 6 h after insemination in both cycloheximide-containing and cycloheximide-free media. Pig oocytes at metaphase II contained two types of MAP kinase – ERK 1 and ERK 2 – in their active phosphorylated forms. At 8 h after insemination ERK 2 changed to the fast-migrating inactive form in the oocytes cultured in both cycloheximide-containing and cycloheximide-free media, although the shift-down was not complete. The change was delayed by 2 h after the degradation of cyclin B1 molecules. These results demonstrate that degradation of pig cyclin B1 molecules corresponds to the transition of the oocytes from metaphase II arrest to anaphase II/telophase II and was followed by MAP kinase dephosphorylation.
影响因子：
2.7
作者：
Moos, J;Xu, Z;Kopf, GS
通讯作者：
Kopf, GS