母源NOTCH1/RBPJ对牛早期胚胎发育的调控作用及其机理研究

母源因子在调控卵母细胞成熟和早期胚胎发育过程中发挥着重要作用。NOTCH信号通路对细胞间信号传递和细胞命运决定至关重要。我们前期研究结果证实NOTCH信号通路关键组分NOTCH1和RBPJ在牛早期胚胎中呈现典型母源效应基因表达模式；抑制NOTCH信号通路影响牛早期胚胎发育，导致组蛋白连接蛋白H1FOO和滋养层标记TFAP2A的表达下调，但是其作用机制还不清楚。基于前期工作，本项目拟通过体外受精、显微注射siRNA/mRNA、抑制剂处理、免疫荧光等技术进一步研究母源NOTCH1和RBPJ对染色质重构的影响及H1FOO是否参与介导，分析NOTCH信号通路在早期胚胎细胞谱系分化的作用及TFAP2A是否参与介导，探讨母源NOTCH1和RBPJ对牛卵母细胞成熟的影响及机制。本项目的开展将进一步理解母源因子在牛早期胚胎发育中重要作用，有助于研发相关技术减少牛早期胚胎死亡，进而提高奶牛繁殖率。

Maternal factors play a key role in oocyte maturation and early embryonic development. NOTCH signaling is essential for correct cell fate decisions. We previously confirmed that NOTCH1/RBPJ (NOTCH pathway components ) mRNAs exhibit the typical expression profile of maternal-effect genes in early bovine embryonic development; inhibition of NOTCH signal pathway can affect the early bovine embryonic development, reduce the expression of linker histone H1FOO and trophectoderm marker TFAP2A mRNA, but the mechanism remains unclear. Based on our previous work, the present project will identify the effect of maternal NOTCH1/RBPJ on chromatin remodeling and if H1FOO is involved，on lineage specification and if TFAP2A is involved, the regulatory role of NOTCH signal pathway in oocyte maturation, fertilization and developmental events of early embryos through adopting the molecular and embryological techniques such as in vitro fertilization, microinjection of siRNA/mRNA, inhibitor treatment, and immunofluorescence. The study will help understand the key role of maternal factors in the early bovine embryonic development, which will help develop the novel technologies to reduce early embryo deaths and thus improve reproductive efficiency in dairy cows.