母体向合子基因表达调控的转变对于人类植入前胚胎发育至关重要。近年来,单细胞RNA测序(scRNA-seq)已被用于检测调控人类卵母细胞成熟和早期胚胎发育的因子。在此,在来自从患者收集的胚胎的单个卵裂球中通过scRNA-seq对转录组进行评估。从7名患者的8细胞胚胎中活检了20个卵裂球,这些患者由于胚胎质量低而接受了两个以上的ART周期。同时,我们从4例因男性因素或输卵管因素而接受ART治疗的患者的8细胞胚胎中收集了10个细胞.然后使用先前建立的scRNA-seq方法评估卵裂球,以确定基因表达与其发育能力之间的关联。在8细胞胚胎中检测到的基因总数减少,这些基因未能形成囊胚,包括母体和合子mRNA。在8细胞胚胎中检测到324个不同表达的基因,包括65个在8细胞胚胎中被显着抑制的基因,这些基因未能形成胚泡。进一步分析发现,这些8细胞胚胎由于细胞周期功能障碍而在卵裂期停滞,DNA转录活性,组蛋白甲基化和细胞分裂相关基因,如SMCO-1,ZNF271P,ZNF679,ASF1b,BEX3、DPPA2和ORC4。在人8细胞胚胎中检测到的基因表达改变与其发育能力密切相关,可以作为增强胚胎发育的目标或预测胚胎发育结果的参数。
The transition of maternal to zygotic gene expression regulation is critical for human preimplantation embryo development. In recent years, single-cell RNA sequencing (scRNA-seq) had been applied to detect the factors that regulate human oocyte maturation and early embryo development. Here, the evaluation of transcriptomes in single blastomere from the embryo collected from patients by scRNA-seq was performed. There were 20 blastomeres biopsied from 8-cell embryos of seven patients who received more than two ART cycles due to low embryo competence. Meanwhile, ten cells were collected from 8-cell embryos of four patients who received ART treatment due to male or tubal factors. The blastomeres were then evaluated using the previously established scRNA-seq method to determine the associations between their gene expression and developmental competence. The total number of genes detected in 8-cell embryos that failed to form blastocyst including maternal and zygotic mRNAs was reduced. There were 324 differently expressed genes detected among the 8-cell embryos including 65 genes that were significantly suppressed in the 8-cell embryos that failed to form blastocyst. Further analysis found these 8-cell embryos arrested at the cleavage stage due to the dysfunction of the cell cycle, DNA transcription activity, histone methylation, and cell division-related genes such as SMCO-1, ZNF271P,ZNF679, ASF1b, BEX3, DPPA2, and ORC4. The alterations of gene expression detected in human 8-cell embryos are tightly associated with its developmental competence and could be used as targets to enhance embryo development or parameters to predict the embryo\'s development outcomes.
Many females are suffering infertility due to the failure of embryonic development at early stages due to unknown causes. At the very beginning of human embryo development, the embryos start to express its own genes, which should be achieved at 8-cell stage. In current research, we isolated one cell from 8-cell embryos and detected the gene expression at single-cell level. Then the remaining cells of these embryos were cultured to form blastocyst. Meanwhile, the data was analyzed according to the outcomes of embryo development. We detected 324 differently expressed genes between the 8-cell embryos that succeeded and failed to form blastocyst. Our research showed the association between the gene expression and the developmental competence of 8-cell embryos. The findings could be used to predict the embryo quality and potential therapy target to improve the efficiency of assisted reproductive techniques.