中文摘要：

目的：探讨小鼠卵母细胞G2期阻滞中，AKAP77是否是介导蛋白激酶A（proteinkinaseA，PKA）锚定在Cdc25B底物蛋白处的A型激酶锚定蛋白（A-kinaseanchoringproteins，AKAPs）。方法：以PKA锚定阻断剂Ht31处理G2期阻滞的小鼠卵母细胞，观察Cdc25B-S321的磷酸化状态，以免疫共沉淀方法检测PKARⅡ-AKAP7y-Cdc25B的相互作用。结果：在G2期阻滞的小鼠卵母细胞中．Ht31处理后Cdc25B-S321不能被PKA磷酸化，同时PKARⅡ-AKAP7Y及AKAP7Y-Cdc25B存在相互作用。结论：在小鼠卵母细胞中，PKA通过AKAP77锚定在胞质中的Cdc25B底物蛋白处，磷酸化其321位丝氨酸，使卵母细胞减数分裂阻滞在G2期，PKARⅡ．AKAP7y／Cdc25B通路在小鼠卵母细胞减数分裂阻滞中发挥重要作用。

英文摘要：

Objective： To seek whether the A-kinase anchoring proteins 7y（AKAPs） regulates the association of PKA and Cdc25B in G2-arrested mouse oocytes, Methods： Ht31 was used to disrupt the association of PKA and its substrates and phosphorylation status of Cdc25B-S321 was examined. The co-immunoprecipita- tion was used to examine the interaction of PKA RII-AKAP7y and AKAP7y-Cdc25B. Results： Phosphorylation reaction mediated by Cdc25B-S321 associated PKA II was inhibited by Ht31 peptide but not by the control peptide Ht31-P. AKAP7y bound PKA RII in overlay assays and also was immunoprecipitated with Cdc25B from G2-arrested mouse oocytes. Conclusion： PKA II is linked physically and functionally to Cdc25B by AKAP interaction, and AKAP7y serves as an AKAP for PKA-mediated phosphorylation of Cdc25B-S321.