The Maternal Environment: Influence on Early Mammalian Development

主要目的：我们的发现研究将侧重于了解能量应激代谢对植入前发育过程中HIPPO途径指导的细胞命运决定的影响。我们将确定胚泡中滋养外胚层（TE）和内细胞团（ICM）细胞系的能量代谢是否存在差异，以及这种差异是否影响HIPPO通路信号的差异激活，从而导致TE分化和ICM多能性的维持。我们的假设是，在植入前发育过程中，通过控制AMPK的能量代谢通过河马通路激活来调节细胞谱系规范。***具体目的是：***1)研究能量应激代谢对HIPPO通路激活和TE细胞谱系分化的影响。***2)对比PI3K、AKT、mTOR和CDK4抑制对着床前胚胎HIPPO通路激活的影响。***3)探讨糖剥夺和糖代谢抑制对着床前胚胎HIPPO通路激活和细胞谱系分化的影响。***4)探讨能量应激介质下调对着床前胚胎HIPPO通路激活和细胞谱系分化的影响。***短期和长期目标：短期目标是研究能量代谢在哺乳动物早期发育过程中的作用，并探索其调控机制。长期目标是了解母体和培养环境对发育中的胚胎的影响，然后应用这些信息来优化胚胎培养环境。***HIPPO通路：HIPPO通路由一系列蛋白激酶组成，包括Mst1/2(HIPPO)；背阔肌½(疣);辅因子Sav1（Salvador）和Mob1a/b (mats)；转录辅助因子Yap1和Taz （Yki）和转录因子TEAD 1-4（扇贝）。最近的研究表明，HIPPO信号在ICM细胞中活跃，导致细胞质磷酸化Yap （Yap-p）阻断TEAD活性。外细胞中有TE祖细胞；HIPPO活性失活，从而允许细胞核Yap和TEAD靶基因表达，导致TE细胞分化。最近的研究表明，能量应激代谢改变了癌细胞中HIPPO的失活。我们预测这种机制在早期胚胎中起作用，通过改变HIPPO通路的活性，我们应该影响早期胚胎的细胞谱系规范。意义：需要研究来定义支持早期发展的所有重要组成部分。我们的实验将揭示有关着床前发育调节的新信息。这些信息是了解环境介质对胚胎发育的影响以及揭示能量应激途径在着床前发育中的功能作用所必需的

Principal Objective: Our discovery research will focus on understanding the impact of energy stress metabolism on HIPPO pathway directed cell fate determination during preimplantation development. We will determine whether trophectoderm (TE) and inner cell mass (ICM) cell lineages in the blastocyst vary in their energy metabolism and whether this variation affects differential activation of HIPPO pathway signaling that results in TE differentiation and maintenance of ICM pluripotency. Our hypothesis is that energy metabolism via control of AMPK regulates cell lineage specification via hippo pathway activation during preimplantation development.***The specific objectives are:***1) To investigate the effects of energy stress metabolism on HIPPO pathway activation and TE cell lineage specification.***2) To contrast effects of PI3K, AKT, mTOR and CDK4 inhibition on HIPPO pathway activation in the preimplantation embryo.***3) To investigate glucose deprivation and inhibition of glucose metabolism on HIPPO pathway activation and cell lineage specification in the preimplantation embryo.***4) To investigate targeted downregulation of energy stress mediators on HIPPO pathway activation and cell lineage specification in the preimplantation embryo. ***Short-and Long Term Goals: The short-term goal is to investigate the role that energy metabolism exerts during early mammalian development and to explore its regulation. The long-term goal is to provide an understanding of the influences that the maternal and culture environments place on the developing embryo and then apply this information to optimize embryo culture environments. ***HIPPO pathway: The HIPPO pathway consists of a series of protein kinases including Mst1/2(Hippo); Lats ½(Warts); cofactors Sav1(Salvador) and Mob1a/b (mats); transcriptional cofactors Yap1 and Taz (Yki) and transcription factors TEAD 1-4 (Scalloped). Recent studies demonstrate that HIPPO signaling is active in ICM cells which results in cytoplasmic phosphorylated Yap (Yap-p) that blocks TEAD activity. In the outer cells ie TE progenitors; HIPPO activity is inactivated thus allowing nuclear Yap and TEAD target gene expression resulting in TE cell differentiation. Recent studies have suggested that energy stress metabolism alters HIPPO inactivation in cancer cells. We predict this mechanism is operating in early embryos and that by altering HIPPO pathway activity we should affect cell lineage specification in the early embryo. ***Significance: Research is required to define all of the vital components that support early development. Our experiments will uncover new information regarding the regulation of preimplantation development. This information is required to understand the effects of environmental mediators on embryonic development and to reveal the functional roles of energy stress pathways during preimplantation development.**