Table_5_C1EIP Functions as an Activator of ENO1 to Promote Chicken PGCs Formation via Inhibition of the Notch Signaling Pathway.docx

The production of germ cells, especially primordial germ cells (PGCs), is important for avian stem cells and reproduction biology. However, key factors involved in the regulation of PGCs remain unknown. Here, we report a PGC-related marker gene: C1EIP (Chromosome 1 Expression in PGCs), whose activation and expression are regulated by the transcription factor STAT3 (signal transducer and activator of transcription 3), histone acetylation, and promoter methylation. C1EIP regulates PGCs formation by mediating the expression of PGC-associated genes, such as CVH (Chicken Vasa Homologous) and CKIT (Chicken KIT proto-oncogene). C1EIP knockdown during embryonic development reduces PGC generation efficiency both in vitro and in ovo. Conversely, C1EIP overexpression increases the formation efficiency of PGCs. C1EIP encodes a cytoplasmic protein that interacts with ENO1 (Enolase 1) in the cytoplasm, inhibits the Notch signaling pathway, and positively regulates PGC generation. Collectively, our findings demonstrate C1EIP as a novel gene involved in PGC formation, which regulates genes involved in embryonic stem cell differentiation through interaction with ENO1 and subsequent inhibition of the Notch signaling pathway by the impression of Myc (MYC proto-oncogene).

生殖细胞（尤其是原始生殖细胞（primordial germ cells，PGCs））的生成，对于鸟类干细胞研究与生殖生物学领域具有重要价值。目前，调控原始生殖细胞的关键因子仍未明确。本研究报道了一种与原始生殖细胞相关的标记基因C1EIP（PGCs中1号染色体表达基因，Chromosome 1 Expression in PGCs），其激活与表达过程受转录因子STAT3（信号转导与转录激活因子3，signal transducer and activator of transcription 3）、组蛋白乙酰化及启动子甲基化共同调控。C1EIP可通过介导鸡Vasa同源基因（CVH，Chicken Vasa Homologous）、鸡KIT原癌基因（CKIT，Chicken KIT proto-oncogene）等原始生殖细胞相关基因的表达，调控原始生殖细胞的形成。在胚胎发育阶段敲低C1EIP，会分别降低体外与卵内的原始生殖细胞生成效率；反之，过表达C1EIP则可提升原始生殖细胞的形成效率。C1EIP编码一种细胞质蛋白，能够在细胞质中与烯醇化酶1（ENO1，Enolase 1）相互结合，抑制Notch信号通路，并对原始生殖细胞的生成起到正向调控作用。综上，本研究证实C1EIP是参与原始生殖细胞形成的新型基因，其通过与ENO1相互作用，并经MYC原癌基因（Myc，MYC proto-oncogene）介导抑制Notch信号通路，进而调控胚胎干细胞分化相关基因的表达。