Laboratory of Cellular and Developmental Biology, NIDDK, National Institutes of Health, Bethesda, MD 20892, USA.
Cell Rep. 2023 Feb 28;42(2):112047. doi: 10.1016/j.celrep.2023.112047. Epub 2023 Jan 30.
Mammalian development is precisely controlled by cell differentiation. Identifying new regulators and investigating their interactions provide insight into genetic networks defining pre-implantation development. We established a knockout mouse model of Dis3, an exosome associated ribonuclease. Homozygous Dis3 null embryos arrest at the morula stage of development. Using single-embryo RNA sequencing (RNA-seq), we observed persistence of Pou6f1 mRNA in homozygous null Dis3 embryos and that the cognate protein represses transcription of Nanog and Cdx2. The resultant defects in cell differentiation disrupt the morula-to-blastocyst transition and are embryonic lethal. Microinjection of Dis3 mRNA into zygotes rescues the phenotype. Point mutations of Dis3 ribonuclease in individual blastomeres prevents their incorporation into embryos. To overcome the paucity of embryos, we derived homozygous Dis3 null mouse embryonic stem cells to identify additional gene targets of POU6F1. Our findings delineate a regulatory pathway of DIS3-POU6F1 in pre-implantation mammalian embryogenesis.
哺乳动物的发育受到细胞分化的精确调控。鉴定新的调控因子并研究它们的相互作用，为研究定义植入前胚胎发育的遗传网络提供了线索。我们建立了 Dis3（一种与外切体相关的核糖核酸酶）敲除小鼠模型。Dis3 纯合缺失的胚胎在桑葚胚阶段停止发育。通过对单个胚胎的 RNA 测序（RNA-seq）分析，我们观察到在 Dis3 纯合缺失的胚胎中 Pou6f1 mRNA 持续存在，而同源蛋白则抑制 Nanog 和 Cdx2 的转录。由此导致的细胞分化缺陷破坏了桑葚胚到囊胚的转变，导致胚胎致死。将 Dis3 mRNA 显微注射到受精卵中可以挽救这种表型。单个卵裂球中的 Dis3 核糖核酸酶点突变可防止其被纳入胚胎。为了克服胚胎数量少的问题，我们衍生了 Dis3 纯合缺失的小鼠胚胎干细胞，以鉴定 POU6F1 的其他基因靶点。我们的研究结果描绘了 DIS3-POU6F1 在植入前哺乳动物胚胎发生中的调控途径。
