Molecular mechanism and physiological meaning of genomic imprinting in mouse stem cell.. Mus musculus

Genomic imprinting is monoallelically expressed genes in a parent-of-origin dependent manner. Genomic imprinting play roles in the growth and homeostasis of in mammal. Therefore, aberrant activation of imprinted genes lead to severe defects in the development and growth. However, activation of silenced allele of imprinted genes is generally observed during the establishment of mouse embryonic stem cells. Similarly, loss-of-imprinting phenomenon was observed in H3K27me3-dependent imprinting in ICM differentiation. The purpose of current experiment is to reveal the underlying mechanism and biological meaning of these loss-of-imprinting in stem cell population through the expression analysis of pre-implantation embryos and cultured embryos at single cell level.

基因组印记（Genomic imprinting）是一类以亲本起源依赖性方式实现单等位基因表达的基因。其在哺乳动物的生长与稳态维持中发挥重要作用，因此印记基因的异常激活会导致发育与生长出现严重缺陷。不过，在小鼠胚胎干细胞的建立过程中，通常可观测到印记基因沉默等位基因的激活现象。类似地，在ICM（内细胞团）分化过程中，也观测到依赖H3K27me3的印记丢失现象。本实验旨在通过对植入前胚胎及体外培养胚胎开展单细胞水平的表达分析，揭示干细胞群体中此类印记丢失现象的潜在机制与生物学意义。