Translocation of phospho-protein kinase Cs implies their roles in meiotic-spindle organization, polar-body emission and nuclear activity in mouse eggs.
Translocation of phospho-protein kinase Cs implies their roles in meiotic-spindle organization, polar-body emission and nuclear activity in mouse eggs.
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DOI：
10.1530/rep.1.00336
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发表时间：
2005-02
期刊：
影响因子：
3.8
通讯作者：
Zhen-Yu Zheng;Qing-zhang Li;Dayuan Chen;H. Schatten;Qing-Yuan Sun
中科院分区：
文献类型：
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作者：
Zhen-Yu Zheng;Qing-zhang Li;Dayuan Chen;H. Schatten;Qing-Yuan Sun
蛋白激酶Cs （PKCs）是一个丝氨酸/苏氨酸蛋白激酶家族，分为三个亚家族：经典、新型和非典型。PKC在生殖细胞中的磷酸化作用尚不明确。在这项研究中，我们描述了磷酸化pkc在小鼠卵母细胞成熟、受精和早期胚胎有丝分裂过程中的亚细胞定位。共聚焦显微镜显示，在胚芽囊泡期，磷酸化pkc （pan）在细胞核中大量分布。生发囊泡破裂后，磷酸化pkc定位于浓缩染色体附近，分布于整个减数分裂纺锤体中，并集中于纺锤体两极。中期后，磷酸化pkc在第一极体发射过程中逐渐向纺锤体中央区转移。精子穿透和电激活后，磷酸化pkc的分布从纺锤体两极向纺锤体中央区转移。第二极体（PB2）挤压后，磷酸化pkc定位于卵母细胞与PB2之间的区域。在受精卵中，phospho-PKC除核仁外主要集中在原核中。磷酸化pkc在原核膜破裂后分散，但在有丝分裂中期分布在整个纺锤体上。结果表明，PKC的激活可能在小鼠卵母细胞减数分裂、受精和早期胚胎有丝分裂过程中调控纺锤体组织和稳定、极体挤压和核活性等方面发挥重要作用。
The protein kinase Cs (PKCs) are a family of Ser/Thr protein kinases categorized into three subfamilies: classical, novel, and atypical. The phosphorylation of PKC in germ cells is not well defined. In this study, we described the subcellular localization of phopho-PKC in the process of mouse oocyte maturation, fertilization, and early embryonic mitosis. Confocal microscopy revealed that phospho-PKC (pan) was distributed abundantly in the nucleus at the germinal vesicle stage. After germinal vesicle breakdown, phospho-PKC was localized in the vicinity of the condensed chromosomes, distributed in the whole meiotic spindle, and concentrated at the spindle poles. After metaphase I, phospho-PKC was translocated gradually to the spindle mid-zone during emission of the first polar body. After sperm penetration and electrical activation, the distribution of phospho-PKC was moved from the spindle poles to the spindle mid-zone. After the extrusion of the second polar body (PB2) phospho-PKC was localized in the area between the oocyte and the PB2. In fertilized eggs, phospho-PKC was concentrated in the pronuclei except for the nucleolus. Phospho-PKC was dispersed after pronuclear envelope breakdown, but distributed on the entire spindle at mitotic metaphase. The results suggest that PKC activation may play important roles in regulating spindle organization and stabilization, polar-body extrusion, and nuclear activity during mouse oocyte meiosis, fertilization, and early embryonic mitosis.