HosseinNia Pouria, Hajian Mehdi, Jafarpour Farnoosh, Hosseini Seyed Morteza, Tahmoorespur Mojtaba, Nasr-Esfahani Mohammad Hossein
Department of Reproductive Biotechnology, Reproductive Biomedicine Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, Iran.
Department of Animal Science, Faculty of Agriculture, Ferdowsi University of Mashhad, Mashhad, Iran.
Cell J. 2019 Jul;21(2):194-203. doi: 10.22074/cellj.2019.5732. Epub 2019 Feb 20.
Two critical points of early development are the first and second lineage segregations, which are regulated by a wide spectrum of molecular and cellular factors. Gene regulatory networks, are one of the important components which handle inner cell mass (ICM) and trophectoderm (TE) fates and the pluripotency status across different mammalian species. Considering the importance of goats in agriculture and biotechnology, this study set out to investigate the dynamics of expression of the core pluripotency markers at the mRNA and protein levels.
In this experimental study, the expression pattern of three pluripotency markers (, and ) and the linage specific markers (, and ) were quantitatively assessed in matured (MII) oocytes and embryos at three distinctive stages: 8-16 cell stage, day-7 (D7) blastocysts and D14 blastocysts. Moreover, expression of , , proteins, and their localization in the goat blastocyst was observed through immunocytochemistry.
Relative levels of mRNA transcripts for Nanog and in D3 (8-16 cell) embryos were significantly higher than D7 blastocysts and mature oocytes, while was only significantly higher than D7 blastocysts. However, the expression pattern of , as an epiblast linage marker, decreased from the oocyte to the D14 stage. The expression pattern of and , as extra embryonic linage markers, also showed a similar trend from oocyte to D3 while their expressions were up-regulated in D14 blastocysts.
Reduction in , , mRNA transcription and a late increase in extra embryonic linage markers suggests that the developmental program of linage differentiation is retarded in goat embryos compared to previously reported data on mice and humans. This is likely related to late the implantation in goats.
早期发育的两个关键点是第一次和第二次谱系分离，它们受多种分子和细胞因子调控。基因调控网络是处理不同哺乳动物物种内细胞团（ICM）和滋养外胚层（TE）命运以及多能性状态的重要组成部分之一。考虑到山羊在农业和生物技术中的重要性，本研究旨在研究核心多能性标志物在mRNA和蛋白质水平的表达动态。
在本实验研究中，对三种多能性标志物（、和）以及谱系特异性标志物（、和）在三个不同阶段的成熟（MII）卵母细胞和胚胎中的表达模式进行了定量评估：8 - 16细胞期、第7天（D7）囊胚和第14天（D14）囊胚。此外，通过免疫细胞化学观察了、、蛋白质在山羊囊胚中的表达及其定位。
Nanog和在D3（8 - 16细胞）胚胎中的mRNA转录本相对水平显著高于D7囊胚和成熟卵母细胞，而仅显著高于D7囊胚。然而，作为上胚层谱系标志物的表达模式从卵母细胞到D14阶段呈下降趋势。作为胚外谱系标志物的和的表达模式从卵母细胞到D3也呈现类似趋势，而它们在D14囊胚中的表达上调。
、、mRNA转录减少以及胚外谱系标志物后期增加表明，与先前报道的小鼠和人类数据相比，山羊胚胎中的谱系分化发育程序受到阻碍。这可能与山羊着床较晚有关。
