生长抑制因子2在植入前小鼠胚胎发育中的作用

目的探讨生长抑制因子2(Ing2)在小鼠植入前胚胎中的表达及生物学功能。方法使用ICR小鼠进行促进排卵以获得植入前胚胎。采用免疫荧光方法对Ing2蛋白在小鼠植入前胚胎中的定位进行研究,采用显微注射Ing2-esiRNA实验对其在早期胚胎中的功能进行研究。抽提小鼠囊胚期合子的RNA反转录为cDNA,进行实时PCR分析。结果免疫荧光结果显示Ing2蛋白在小鼠植入前胚胎中定位于胞浆及胞核。从4-cell期胚胎开始,胞核中的表达量明显增高。Ing2-esiRNA显微注射实验显示在小鼠合子中干扰Ing2后,各期胚胎形成率均显著低于对照组(4-cell期胚胎比率:82.7%vs.94.7%;桑葚胚比率:67.3%vs.89.4%;囊胚形成率:48.7%vs.75.8%)(P<0.01)。结论 Ing2的下调,引起植入前小鼠胚胎发育阻滞。

Role of inhibitor of growth 2 in the development of mouse preimplantation embryo

Objective To investigate the expression and function of inhibitor of growth 2(Ing2) in the development of preimplantation embryo.Methods ICR mice were treated with promoting ovulation for preimplantation embryos.Immunofluorescence was used to determine the cellular distribution of Ing2 in stages of preimplantation embryos.EsiRNA microinjection was performed to study its function in preimplantation embryos.The RNA of blastocyst stage mouse zygotic was reversely transcriped to cDNA,which was analyzed with real time-PCR.Results Ing2 was localized in the cytoplasm and nucleus of all stages of preimplantation mouse embryos.The expression of Ing2 was significantly higher in the nucleus than in the cytoplasm since the 4-cell stage embryos.The functional inhibition of Ing2 by esiRNA microinjection led to developmental retardation.A significant growth-inhibitory effect on embryonic development was observed in the Ing2 RNAi-injected groups when compared with the nonsilenced esiRNA-injected groups(82.7% vs.94.7% for 4-cell stage embyo,67.3% vs.89.4% for morula stage embyo,48.7% vs.75.8% for blastocyst)(P<0.01).ConclusionIng2 may play an important role in the development of mouse preimplantation embryos.