Yu Haotian, Shi Yan, Wu Xiaotong, Hu Bingjie, Jin Hao, Kassim Yassin, Iqbal Tariq, Kandil Omaima Mohamed, Ismail Esraa Aly, Wang Huanan, Wang Shaohua, Zhang Kun
Reproduction. 2025 Feb 4;169(3). doi: 10.1530/REP-24-0307. Print 2025 Mar 1.
Transcription factors are crucial for lineage specification in the preimplantation development of mammals. This research shows that TEAD3 and TEAD4 play important and overlapping functions in directing trophectoderm fate decisions during this developmental stage in cattle.
During mammalian preimplantation development, the transition from morula to blastocyst is a critical biological event. This process involves polarization and initial specification of lineages, regulated by various transcription factors that have been extensively studied in mice. Our single-cell RNA sequencing analyses revealed that TEAD3 is specifically expressed in the trophectoderm cells of bovine preimplantation embryos, unlike in mice. The objective of this study is to determine the functional role of TEAD3 in bovine preimplantation development. While TEAD3 knockdown does not affect blastocyst formation in cattle, embryos fail to progress to the blastocyst stage when both TEAD3 and TEAD4, another member of the TEAD family, are disrupted using RNA interference and base editing techniques, respectively. This finding suggests a redundant role for TEAD3 and TEAD4 during preimplantation development in cattle. RNA sequencing analysis identified dysregulation of 215 genes, with 53 genes upregulated and 162 genes downregulated. Notably, we observed a reduction in the expression of trophectoderm lineage-specific genes KRT8, KRT18 and EZR and HIPPO signaling pathway components. Immunofluorescence analysis further revealed that the protein expression levels of KRT8 and EZR were significantly decreased. Importantly, the initial expression of trophectoderm lineage-specific genes, such as TFAP2C and GATA3, and the inner cell mass lineage-specific genes, such as OCT4, remained unaffected. This contrasts with the role of TEAD4 in directly regulating the trophectoderm lineage specification in mice. Thus, our studies demonstrate that TEAD3 and TEAD4 play essential and redundant roles upstream of trophectoderm fate decisions during preimplantation development in cattle.
转录因子对于哺乳动物植入前发育过程中的谱系特化至关重要。本研究表明，在牛的这一发育阶段，TEAD3和TEAD4在指导滋养外胚层命运决定方面发挥着重要且重叠的功能。
在哺乳动物植入前发育过程中，从桑椹胚到囊胚的转变是一个关键的生物学事件。这一过程涉及细胞极化和谱系的初始特化，受多种转录因子调控，这些转录因子在小鼠中已得到广泛研究。我们的单细胞RNA测序分析表明，与小鼠不同，TEAD3在牛植入前胚胎的滋养外胚层细胞中特异性表达。本研究的目的是确定TEAD3在牛植入前发育中的功能作用。虽然敲低TEAD3不影响牛的囊胚形成，但当分别使用RNA干扰和碱基编辑技术破坏TEAD3和TEAD4（TEAD家族的另一个成员）时，胚胎无法发育到囊胚阶段。这一发现表明TEAD3和TEAD4在牛植入前发育过程中具有冗余作用。RNA测序分析确定了215个基因的表达失调，其中53个基因上调，162个基因下调。值得注意的是，我们观察到滋养外胚层谱系特异性基因KRT8、KRT18和EZR以及HIPPO信号通路成分的表达降低。免疫荧光分析进一步显示，KRT8和EZR的蛋白表达水平显著降低。重要的是，滋养外胚层谱系特异性基因（如TFAP2C和GATA3）以及内细胞团谱系特异性基因（如OCT4）的初始表达不受影响。这与TEAD4在小鼠中直接调节滋养外胚层谱系特化的作用形成对比。因此，我们的研究表明，TEAD3和TEAD4在牛植入前发育过程中滋养外胚层命运决定的上游发挥着重要且冗余的作用。
