Laurent A, Basset M, Dorée M, Le Peuch C J
INSERM U.249, CNRS LP 8402, Montpellier, France.
FEBS Lett. 1988 Jan 4;226(2):324-30. doi: 10.1016/0014-5793(88)81448-0.
It has been described that phosphorylation, and dephosphorylation, of specific proteins is associated with key events of the cell cycle and is likely to be due to activation of kinase(s). From our results, the presence of calcium-phospholipid-dependent protein kinase (PKC) was clearly demonstrated in both the cytosolic and particulate fractions of immature Xenopus laevis oocytes and in the cytosolic fraction of mature oocytes. However, it was less active in metaphase II- than in prophase I-arrested oocytes. The enzyme was partially purified by DEAE-cellulose and phenyl-Sepharose chromatography. It was activated in vitro by the tumor-promoting phorbol ester, 12-O-tetradecanoyl phorbol 13-acetate (TPA) as already described for PKC from other tissues. On the other hand, a calcium-phospholipid-independent histone kinase activity 4-fold higher in metaphase II- than in prophase I-arrested oocytes was detected. The possible role of PKC and phospholipid-independent histone kinase in the maturation process is discussed.
据描述，特定蛋白质的磷酸化和去磷酸化与细胞周期的关键事件相关，并且可能是由于激酶的激活所致。从我们的结果来看，在未成熟非洲爪蟾卵母细胞的胞质和颗粒部分以及成熟卵母细胞的胞质部分中，钙磷脂依赖性蛋白激酶（PKC）的存在都得到了明确证实。然而，它在中期II期阻滞的卵母细胞中的活性低于前期I期阻滞的卵母细胞。该酶通过DEAE - 纤维素和苯基 - 琼脂糖层析进行了部分纯化。如已针对其他组织的PKC所描述的那样，它在体外被促肿瘤佛波酯12 - O - 十四酰佛波醇13 - 乙酸酯（TPA）激活。另一方面，检测到一种钙磷脂非依赖性组蛋白激酶活性，在中期II期阻滞的卵母细胞中比前期I期阻滞的卵母细胞高4倍。文中讨论了PKC和磷脂非依赖性组蛋白激酶在成熟过程中的可能作用。
