CDC25B蛋白S149/S321位点突变对小鼠1-细胞期受精卵发育的影响  

Mutation of S149 and S321 Sites of CDC25B Protein on Development of 1-Cell Stage of Fertilized Mouse Eggs

作　　者：刘超[1,2] 肖建英[1,2] 孙小涵[1,2] 徐晓燕[1] 于秉治[1] 

机构地区：[1]中国医科大学生物化学与分子生物学教研室,沈阳110001 [2]辽宁医学院生物化学与分子生物学教研室,锦州121001

出　　处：《生殖与避孕》2012年第2期73-80,共8页Reproduction and Contraception

摘　　要：目的:研究小鼠CDC25B蛋白S149位点对小鼠1-细胞期受精卵发育的影响及S149位点与S321位点的关系。方法:构建pBSK-CDC25B-S149A和pBSK-CDC25B-S149A/S321A突变体,体外转录成mRNA;采用小鼠超排卵技术取G1期受精卵,显微注射CDC25B-WT-mRNA和突变CDC25B-S149A-mRNA、CDC25B-S149A/S321A-mRNA,观察其对受精卵发育、M期促进因子(MPF)活性及CDC2-pTyr15磷酸化状态的影响。结果:CDC25B-S149A-mRNA注射组受精卵卵裂率明显高于CDC25B-WT-mRNA注射组,MPF活性提前1 h达到高峰;而联合突变体CDC25B-S149A/S321A-mRNA注射组卵裂率又显著高于CDC25B-S149A-mRNA注射组。结论:在小鼠1-细胞期受精卵有丝分裂过程中,蛋白激酶A(PKA)对小鼠CDC25B蛋白S149位点的磷酸化修饰是控制受精卵G2/M转换的重要方式,并且S149位点与S321位点可能具有协同作用。Objective：To investigate the role of Ser149 of CDC25B in 1-cell stage of fertilized mouse eggs and the relationship between Ser149 and Ser 321 sites.Methods： pBSK-CDC25B-S149A and pBSK-CDC25BS149A/S321A mutants were constructed and transcribed into mRNAs in vitro.CDC25B-WT-mRNA,CDC25BS149A-mRNA and CDC25B-S149A/S321A-mRNA were respectively microinjected into the mouse fertilized eggs in G1phase after superovulation.Furthermore,the cleavage rate,MPF activity and phosphorylation status of CDC2-pTyr15 in fertilized eggs were observed.Results： Cleavage rate of fertilized eggs in CDC25BS149A-mRNA injected group was significantly higher than that of CDC25B-WT-mRNA group,and the peak of MPF activity appeared in the CDC25B-S149A-mRNA group,about 1 h early compared with the CDC25B-WTmRNA group.While the cleavage rate in CDC25B-S149A/S321A-mRNA group was significantly higher than that in CDC25B-S149A-mRNA group.Conclusion： PKA regulates the early development of mouse embryos by phosphorylation of S149 of CDC25B,and the residue Ser149 of CDC25B cooperates with Ser321,which plays an important role in the regulation of G2/M transition in the mitotic cell cycle of fertilized mouse eggs.

关 键 词：CDC25B蛋白 蛋白激酶A(PKA) M期促进因子(MPF) 小鼠受精卵 

分 类 号：R-33[医药卫生]