Boyer J, Bellé R, Capony J P, Ozon R
Biochimie. 1983 Jan;65(1):15-23. doi: 10.1016/s0300-9084(83)80024-8.
In ovo [32P] phosphoproteins were analyzed during meiotic maturation of Xenopus laevis oocytes. A phosphoprotein of 105,000-dalton was found to increase early (one hour) after progesterone induction of meiosis. The pure heat-stable inhibitor (PKI) of cAMP-dependent protein kinase, which induces maturation, was microinjected into oocytes. Again the early increase in the 105,000-dalton [32P] phosphoprotein occurred. The burst in protein phosphorylation, which takes place at the period of germinal vesicle breakdown, was quantitatively and qualitatively comparable in progesterone and PKI-stimulated oocytes. In order to confirm the inverse relationship between the 105,000 dalton [32P] phosphoprotein increase and cAMP-dependent protein kinase activity, purified C-subunit of the kinase has been microinjected into oocytes. C-subunit which inhibits maturation did not increase significantly the 105,000-dalton [32P] phosphoprotein whereas it increased the total level of in ovo phosphorylation. Enucleation experiments favour the localization of the 105,000-dalton protein in both the oocyte cytoplasm and nucleus. Furthermore the progesterone-induced increase in the phosphorylation of the 105,000-dalton protein was found in the cytoplasmic compartment after oocyte enucleation.
在非洲爪蟾卵母细胞减数分裂成熟过程中，对卵内[32P]磷蛋白进行了分析。发现一种105,000道尔顿的磷蛋白在孕酮诱导减数分裂后早期（1小时）增加。将能诱导成熟的cAMP依赖性蛋白激酶的纯热稳定抑制剂（PKI）显微注射到卵母细胞中。105,000道尔顿的[32P]磷蛋白同样在早期增加。在生发泡破裂期发生的蛋白质磷酸化爆发，在孕酮和PKI刺激的卵母细胞中，在数量和质量上具有可比性。为了证实105,000道尔顿的[32P]磷蛋白增加与cAMP依赖性蛋白激酶活性之间的反向关系，已将纯化的激酶C亚基显微注射到卵母细胞中。抑制成熟的C亚基并没有显著增加105,000道尔顿的[32P]磷蛋白，而它增加了卵内磷酸化的总水平。去核实验表明105,000道尔顿的蛋白定位于卵母细胞的细胞质和细胞核中。此外，在卵母细胞去核后，在细胞质部分发现了孕酮诱导的105,000道尔顿蛋白磷酸化增加。
