小鼠卵母细胞减数分裂过程中PAK1与survivin的亚细胞定位和蛋白水平相关

PAK1 correlation with the subcellular localization and protein level of survivin in mouse oocyte meiosis

目的研究小鼠卵母细胞减数分裂进程中,活化的PAK1(pPAK1^(Thr423))在存活蛋白(survivin)的时空定位和蛋白水平维持中的相关性。方法利用免疫荧光染色法分析减数分裂进程中pPAK1^(Thr423)与survivin的时空相关性;利用Western blot分析PF3758309对survivin蛋白水平的影响。结果在小鼠卵母细胞第一次减数分裂中期(MⅠ),pPAK1^(Thr423)和survivin共同聚集在MⅠ期同源染色体臂间以及着丝粒上,在第二次减数分裂中期(MⅡ),两者仍旧共同集中在着丝粒上,其在染色体臂间的聚集仅限于姊妹着丝粒之间的区域;PAK抑制剂PF3758309处理引起survivin蛋白水平的降低。结论小鼠卵母细胞减数分裂过程中,pPAK1^(Thr423)可能通过调控survivin在染色体臂间和着丝粒上的聚集和有效水平的维持参与染色体乘客复合体(CPC)调控染色体分离的过程。

Objective To study the relationship of activated PAK1 (pPAK1 Thr423 ) with the subcellular localization and protein level maintenance of survivin in the meiotic progression of mouse oocytes. Methods Immunofluorescent staining was employed to analyze the spatial-temporal correlation between pPAK1 Thr423 and survivin during oocyte meiosis;Western blot was applied to analyze the change of survivin level in oocytes treated with PF3758309. Results In mouse oocytes at metaphase Ⅰ stage (MⅠ), pPAK1 Thr423 was co-localized with survivin between chromosome arms and on centromeres of homologous chromosomes, the centromeric co-lozalization remained at metaphase Ⅱ stage (MⅡ), while that across chromosome axis was confined in the local space between sister centromeres. The protein level of survivin significantly decreased in oocytes treated with PF3758309. Conclusions pPAK1 Thr423 may regulate the subcellular localization and protein maintenance of survivin, so as to participate in CPC regulating chromosome separation in mouse oocyte meiosis.