The Maternal Environment: Influence on Early Mammalian Development

母体环境：对哺乳动物早期发育的影响

• 批准号: RGPIN-2016-04740
• 负责人: Watson, Andrew
• 金额: $ 2.26万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=668261
• 关键词: Maternal; Environment; Influence; Early; Mammalian

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.**

主要目标：我们的发现研究将重点了解植入前发育过程中能量应激代谢对 HIPPO 通路定向细胞命运决定的影响。我们将确定囊胚中滋养外胚层 (TE) 和内细胞团 (ICM) 细胞谱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 进行能量代谢，通过 hippo 通路激活来调节细胞谱系规范。***具体目标是：***1) 研究能量应激代谢对 HIPPO 通路激活和 TE 细胞谱系规范的影响。***2) 对比 PI3K、AKT、mTOR 和 CDK4 抑制对 HIPPO 通路激活的影响 ***3) 研究葡萄糖剥夺和葡萄糖代谢抑制对植入前胚胎中 HIPPO 通路激活和细胞谱系规范的影响。***4) 研究能量应激介质的定向下调对植入前胚胎中 HIPPO 通路激活和细胞谱系规范的影响。 ***短期和长期目标：短期目标是研究能量代谢在早期哺乳动物发育过程中发挥的作用并探索其调节。长期目标是了解母体和培养环境对胚胎发育的影响，然后应用这些信息来优化胚胎培养环境。 ***HIPPO通路：HIPPO通路由Mst1/2(Hippo)等一系列蛋白激酶组成；背阔肌 ½（疣）；辅因子 Sav1（萨尔瓦多）和 Mob1a/b（垫子）；转录辅因子 Yap1 和 Taz (Yki) 以及转录因子 TEAD 1-4 (Scalloped)。最近的研究表明，HIPPO 信号传导在 ICM 细胞中活跃，导致细胞质磷酸化 Yap (Yap-p)，从而阻断 TEAD 活性。在外部细胞中，即 TE 祖细胞； HIPPO 活性失活，从而允许核 Yap 和 TEAD 靶基因表达，导致 TE 细胞分化。最近的研究表明，能量应激代谢会改变癌细胞中 HIPPO 的失活。我们预测这种机制在早期胚胎中发挥作用，并且通过改变 HIPPO 通路活性，我们应该会影响早期胚胎中的细胞谱系规范。 ***意义：需要进行研究来定义支持早期发育的所有重要组成部分。我们的实验将揭示有关植入前发育调节的新信息。需要这些信息来了解环境介质对胚胎发育的影响，并揭示能量应激途径在植入前发育过程中的功能作用。 **