调控合子DNA 甲基化及合子转录激活的母源因子的鉴定及其作用机理

项目名称： 调控合子DNA 甲基化及合子转录激活的母源因子的鉴定及其作用机理

项目编号： No.31330052

项目类型： 重点项目

立项/批准年度： 2014

项目学科： 生物科学

项目作者： 孟安明

作者单位： 清华大学

项目金额： 299万元

中文摘要： 在动物胚胎发育过程中，受精后合子基因组处于转录抑制状态，到一定阶段合子基因才转录激活。合子基因的转录激活与基因组DNA 去甲基化密切相关，合子基因组DNA的去甲基化由母源因子调控。目前对于参与脊椎动物受精卵合子基因组去甲基化的母源因子和作用机理所知甚少，亟待利用好的实验系统去探究。本项目拟以斑马鱼为对象，通过ENU 大规模诱变，甲基化胞嘧啶（5mC）抗体免疫染色筛选，鉴定基因组DNA 甲基化水平明显上升的突变体，从而发现具有DNA 去甲基化功能的母源因子，并研究它们的作用机理和对合子基因激活、胚层形成与分化、组织器官发育的影响。本项目可望发现调控合子基因组甲基化水平的新的去甲基化因子和信号通路，加深对胚胎早期发育调控的分子机理的认识。

中文关键词： DNA去甲基化;合子基因激活;化学诱变;胚胎发育;斑马鱼

英文摘要： During animal embryogenesis, the zygotic genome is inactivated for transcription upon fertilization and its transcription will occur after a certain period of development. The transcriptional activation of the zygotic genome is closely related to DNA demethylation of the genome, a process controlled by maternal factors. However, it remains unclear which maternal factors are involved in DNA demethylation of the zygotic genome following fertilization and how they function and regulate embryonic development. This project aims to identify maternal factors that regulating DNA demethylation of the zygotic genome and to investigate their roles in zygotic gene activation and embryonic development. To achieve these goals, ENU mutagenesis will be performed in zebrafish; mutants with the disability of DNA demethylation during the cleavage period will be identified by immunostaining with anti-5mC antibody; and the mutant genes will be mapped and cloned. The mutant embryos will be investigated for any defects in zygotic gene activation, germ layer formation and patterning, and organogenesis. The mechanisms of DNA demethylation of the identified factors will also be investigated through biochemical and genetic approaches. The accomplishment of this study would allow the discovery of new demethylation factors and new demethylation pathways, ultimately deepening our understanding of zygotic gene activation and embryonic development in vertebrates.

英文关键词： DNA demethylation;zygotic gene activation;chemical mutagenesis;embryogenesis;zebrafish