基因组印迹是哺乳动物胚胎及成体发育所必需的表观遗传修饰。我们的前期研究发现DNA甲基化和组蛋白修饰对早期胚胎发育及印迹基因的表达具有重要调控作用。在本申请中我们将以原核移植重构的孤雌和孤雄二倍体胚胎为研究对象，用微量组学技术对早期及着床后胚胎印迹建立及维持的机制进行研究：从转录组水平研究不同亲本来源基因的表达情况并筛选新的潜在印迹基因，并通过不同品系杂交胚胎进行验证；通过全基因组甲基化测序(WGBS)及微量细胞Chip-seq技术研究亲本间差异DNA甲基化和H3K9me3修饰在早期胚胎发育中的建立模式；进一步通过H3K9me3去甲基化酶Kdm4b研究H3K9me3对印迹基因的调控作用；通过CRISPR/Cas9敲除技术对新发现的潜在印迹基因进行验证和功能性研究。从而揭示早期胚胎印迹基因建立及维持的分子机制，为以后印迹基因相关疾病的诊断及治疗提供实验基础。

Genomic imprinting as a critical epigenetic modification is necessary for mammalian embryo and adult development. Our previous studies found that DNA methylation and histone modifications play an important roles in early embryo development and imprinting gene expression. In the present application, we will use the reconstructed androgenetic and gynogenetic diploid embryos as models to research the mechanism of imprinted genes in early embryonic development. Firstly, we will investigate the allelic gene expression and screen the potential imprinted genes in early embryo development. Genome-wide methylation sequencing (WGBS) and Chip-seq are used to investigate the pattern of differentially methylated regions in imprinted genes. We will further study the regulatory effect of H3K9me3 modification related to the imprinting gene expression by injecting histone demethylase (Kdm4b) into embryos. We will aim to reveal the mechanism of imprinting gene establish and maintain in early embryo development and provide a scientific experimental basis for the diagnosis and treatment of genetic imprinted diseases.