Jiangsu Livestock Embryo Engineering Laboratory, College of Animal Science and Technology, Nanjing Agricultural University, Nanjing, China.
Biol Reprod. 2018 Oct 1;99(4):707-717. doi: 10.1093/biolre/ioy118.
In mammals, their proper development during the early cleavage stages strongly relies on the gene products newly transcribed by zygotic genome activation (ZGA). Long noncoding RNAs (lncRNAs) have been characterized as key regulators of the ZGA process in mice and human. However, the ZGA stage has not yet been identified and epigenetic regulations of the ZGA process remain largely unknown in goats. Here, we show that ZGA occurred at the 8-cell stage in goats. During ZGA, trimethylation of H3K9 was dynamically changed but maintained strong staining in development arrested embryos. Using single-cell RNA sequencing, we identified 800 mRNAs and 250 lncRNAs as candidates of key molecules in goat preimplantation embryos. These mRNAs and lncRNAs were differentially expressed from 4- to 8-cell stage embryos and were strongly enriched in terms of retinoic acid receptor signaling pathway as well as signaling pathway regulating pluripotency of stem cells. In particular, we found that microinjection of siRNA against lnc_137 caused development arrest. Our results are consistent with the notion that lncRNAs play vital roles during ZGA, and the data presented here provide an excellent source for further ZGA lncRNA studies.
在哺乳动物中，早期卵裂阶段的正常发育强烈依赖于合子基因组激活 (ZGA) 时新转录的基因产物。长非编码 RNA (lncRNA) 已被鉴定为小鼠和人类 ZGA 过程的关键调控因子。然而，山羊中的 ZGA 阶段尚未被确定，ZGA 过程的表观遗传调控仍知之甚少。在这里，我们表明 ZGA 发生在山羊的 8 细胞阶段。在 ZGA 过程中，H3K9 的三甲基化动态变化，但在发育停滞的胚胎中保持强烈染色。使用单细胞 RNA 测序，我们鉴定了 800 个 mRNA 和 250 个 lncRNA 作为山羊植入前胚胎中关键分子的候选物。这些 mRNA 和 lncRNA 从 4-到 8 细胞胚胎表达差异，并在视黄酸受体信号通路以及干细胞多能性调节信号通路方面强烈富集。特别是，我们发现针对 lnc_137 的 siRNA 的显微注射导致发育停滞。我们的结果与 lncRNA 在 ZGA 中发挥重要作用的观点一致，并且这里呈现的数据为进一步的 ZGA lncRNA 研究提供了极好的资源。
