NRF1与DNA甲基化的相互调控在雄性生殖发育中的作用及分子机制

DNA methylation is an important epigenetic modification that plays a unique role in mammalian germ cell development, but its interaction with transcription factors remains unclear. NRF1 is a nuclear DNA-coded transcription factor, but known for its function in regulating mitochondrial respiratory gene expression and metabolism. DNMT1 is partially localized at mitochondria and can be upregulated by NRF1 under condition of hypoxia, indicating a regulatory role of NRF1 on DNA methylation. Our preliminary data indicate that NRF1 coordinates DNA methylation to regulate expression of germline genes. In addition, conditional depletion of NRF1 from germ cells or Sertoli cells led to dramatically reduced fertility in mice. In order to fully understand the relationship of NRF1 and DNA methylation during male germ cell development, we plan to further utilize NRF1 conditional knockout mouse model, in combination of in vitro culture of spermatogonial stem cells, differentiation system of pluripotent stem cells, and biochemical assays. We will determine the function and its relationship of NRF1 with DNA methylation at different stages in male germ cell development. Additionally, we will explore the interaction of NRF1 and DNA methylation upon metabolic stimuli in germ cells. Finally, we will investigate the role of NRF1 in the directed differentiation of pluripotent stem cells toward germ cell lineages. Our study will shed light on our understanding in mammalian germ cell development and contribute to clinical drug discovery for human infertility.

DNA甲基化与转录因子间的互作对生殖的影响目前尚不清楚，NRF1是一种核基因编码的转录因子，调控线粒体呼吸链基因的表达，影响线粒体代谢，在雄性生殖发育中的作用尚无报道。DNA甲基转移酶DNMT1部分定位于线粒体，在低氧时被NRF1上调,暗示了NRF1对DNA甲基化的影响。我们的初步结果表明NRF1与DNA甲基化共同调控生殖相关基因的表达；NRF1在生殖细胞或Sertoli细胞中的特异性敲除会导致雄性生育能力的下降。为了进一步阐明NRF1与DNA甲基化的互作在雄性生殖中的作用，我们拟利用NRF1条件敲除小鼠模型，结合胚胎干细胞及精原干细胞的体外分化体系，确定NRF1在不同时期雄性生殖细胞发育中的功能及与DNA甲基化的互作；揭示NRF1在维持睾丸微环境中的作用；探讨代谢改变时NRF1与DNA甲基化的相互作用；明确NRF1对多能性干细胞向生殖细胞分化的影响，为不育不孕的基因治疗提供新的思路。

DNA甲基化与转录因子间的互作对生殖的影响目前尚不清楚，NRF1是一种核基因编码的转录因子，调控线粒体呼吸链基因的表达，影响线粒体代谢，在雄性生殖发育中的作用尚无报道。我们通过DDX4-CRE及TNAP-CRE在生殖发育的不同阶段在生殖细胞内条件敲除NRF1，结果表明NRF1与DNA甲基化协同调控生殖相关基因的表达；NRF1不影响原始生殖细胞在生殖嵴的定植，但影响其增殖。为了进一步阐明NRF1与DNA甲基化的互作在雄性生殖中的作用，我们利用胚胎干细胞的体外分化体系，发现NRF1的高表达促进原始生殖细胞的发育，我们将进一步通过RNA-seq, CHIP-seq及与DNA甲基化检测揭示NRF1的作用机制，明确NRF1与DNA甲基化及代谢的相互作用，为不育不孕的基因治疗提供新的思路。