蛋白激酶C在哺乳动物卵子受精过程中的作用

蛋白激酶C(PKC)被认为是在哺乳动物受精期间卵母细胞激活的主要调节者。在哺乳动物卵子的受精过程中，PKC可能作为卵子活化过程中Ca^2 的重要下游靶分子，启动皮质颗粒的排放，并使卵子突破MⅡ期阻滞，促使细胞周期恢复和原核形成。早期采用药物激活和抑制PKC获得了大量支持上述观点的证据，然而，有些研究结果与PKC调节卵子激活的作用相矛盾，故目前无法得到确切的结论。由于哺乳动物的卵子表达许多不同的。PKC亚型，并且它们的空间结构、辅助因子和作用底物存在区别。因此，需要更为全面地重新认识卵子中PKCS的作用。本文就PKC的生物化学特性、最近有关哺乳动物受精过程中PKC作用的实验证据以及某些PKC亚型在受精一诱导卵子激活中具有的特殊作用的研究近况作一综述。

Protein Kinases C Involved in the Fertilization of Mammalian Eggs

Protein kinase C (PKC) has been proposed to regulate major egg activation events during mammalian fertilization. Most of the evidence supporting this assumption that PKC is involved in the activation of eggs as a downsterm regulator of Ca2+, and they induce the cortical granule exocytosis, trigger the resumption of the second meiotic division and the formation of pronuclei by using pharmacological activation and inhibition of the kinase. However, some results are contrast to the exact role of PKC in regulating egg activation events, so results have been inconclusive. Mammalian eggs express many isotypes with different modular structures and cofactor requirements, which may underlie their different substrate specificities. Hence, the need to re-examine the roles of egg PKCs more specifically. Here, we will review the biochemical property of PKC, and the experimental evidence supporting a role for PKC during mammalian fertilization and focus on recent studies that have investigated the role of several specific PKC isotypes in fertilization-induced egg activation.