Li Conghui, Zhang Yue, Leng Lizhi, Pan Xiaoguang, Zhao Depeng, Li Xuemei, Huang Jinrong, Bolund Lars, Lin Ge, Luo Yonglun, Xu Fengping
College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.
BGI-Shenzhen, Beishan Industrial Zone, Shenzhen, China.
Front Cell Dev Biol. 2022 Nov 11;10:1020490. doi: 10.3389/fcell.2022.1020490. eCollection 2022.
Transposable elements (TEs) and transcription factors (TFs) are involved in the precise regulation of gene expression during the preimplantation stage. Activation of TEs is a key event for mammalian embryonic genome activation and preimplantation early embryonic development. TFs are involved in the regulation of drastic changes in gene expression patterns, but an inventory of the interplay between TEs and TFs during normal/abnormal human embryonic development is still lacking. Here we used single-cell RNA sequencing data generated from biparental and uniparental embryos to perform an integrative analysis of TE and TF expression. Our results showed that endogenous retroviruses (ERVs) are mainly expressed during the minor embryonic genome activation (EGA) process of early embryos, while Alu is gradually expressed in the middle and later stages. Some important ERVs (e.g., LTR5_Hs, MLT2A1) and Alu TEs are expressed at significantly lower levels in androgenic embryos. Integrative analysis revealed that the expression of the transcription factors and is correlated with the differential expression of ERV TEs. Comparative coexpression network analysis further showed distinct expression levels of important TFs (e.g., and ) in dizygotic embryos vs. parthenogenetic and androgenic embryos. This systematic investigation of TE and TF expression in human early embryonic development by single-cell RNA sequencing provides valuable insights into mammalian embryonic development.
转座元件（TEs）和转录因子（TFs）参与着床前阶段基因表达的精确调控。TEs的激活是哺乳动物胚胎基因组激活和着床前早期胚胎发育的关键事件。TFs参与基因表达模式剧烈变化的调控，但在正常/异常人类胚胎发育过程中，TEs与TFs之间相互作用的清单仍缺失。在此，我们使用来自双亲胚胎和单亲胚胎的单细胞RNA测序数据，对TE和TF的表达进行综合分析。我们的结果表明，内源性逆转录病毒（ERVs）主要在早期胚胎的次要胚胎基因组激活（EGA）过程中表达，而Alu在胚胎发育的中晚期逐渐表达。一些重要的ERVs（如LTR5_Hs、MLT2A1）和Alu转座元件在孤雄胚胎中的表达水平显著较低。综合分析显示，转录因子 和 的表达与ERV转座元件的差异表达相关。比较共表达网络分析进一步表明，重要转录因子（如 和 ）在二合子胚胎与孤雌生殖和孤雄胚胎中的表达水平不同。通过单细胞RNA测序对人类早期胚胎发育中TE和TF表达进行的这项系统研究，为哺乳动物胚胎发育提供了有价值的见解。
