Department of Agricultural Biotechnology, Animal Biotechnology Major, and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, South Korea.
Institute of Green Bio Science and Technology, Seoul National University, Pyeongchang, South Korea.
Cell Prolif. 2022 Nov;55(11):e13313. doi: 10.1111/cpr.13313. Epub 2022 Jul 26.
Curiosity about the role of OCT4, a core transcription factor that maintains inner cell mass (ICM) formation during preimplantation embryogenesis and the pluripotent state in embryonic development, has long been an issue. OCT4 has a species-specific expression pattern in mammalian preimplantation embryogenesis and is known to play an essential role in ICM formation. However, there is a need to study new roles for OCT4-related pluripotency networks and second-cell fate decisions.
To determine the functions of OCT4 in lineage specification and embryo proliferation, loss- and gain-of-function studies were performed on porcine parthenotes using microinjection. Then, we performed immunocytochemistry and quantitative real-time polymerase chain reaction (PCR) to examine the association of OCT4 with other lineage markers and its effect on downstream genes.
In OCT4-targeted late blastocysts, SOX2, NANOG, and SOX17 positive cells were decreased, and the total cell number of blastocysts was also decreased. According to real-time PCR analysis, NANOG, SOX17, and CDK4 were decreased in OCT4-targeted blastocysts, but trophoblast-related genes were increased. In OCT4-overexpressing blastocysts, SOX2 and NANOG positive cells increased, while SOX17 positive cells decreased, and while total cell number of blastocysts increased. As a result of real-time PCR analysis, the expression of SOX2, NANOG, and CDK4 was increased, but the expression of SOX17 was decreased.
Taken together, our results demonstrated that OCT4 leads pluripotency in porcine blastocysts and also plays an important role in ICM formation, secondary cell fate decision, and cell proliferation.
好奇心驱使人们研究 OCT4 的作用，该转录因子是哺乳动物植入前胚胎发生和胚胎发育中多能性的内细胞团（ICM）形成的核心。OCT4 在哺乳动物植入前胚胎发生中具有种属特异性表达模式，已知其在 ICM 形成中发挥重要作用。然而，需要研究与 OCT4 相关的多能性网络和第二细胞命运决定的新作用。
为了确定 OCT4 在谱系特化和胚胎增殖中的功能，我们使用微注射对猪孤雌胚胎进行了失活和功能获得研究。然后，我们进行免疫细胞化学和定量实时聚合酶链反应（PCR），以检查 OCT4 与其他谱系标记的关联及其对下游基因的影响。
在 OCT4 靶向的晚期囊胚中，SOX2、NANOG 和 SOX17 阳性细胞减少，囊胚的总细胞数也减少。根据实时 PCR 分析，OCT4 靶向的囊胚中 NANOG、SOX17 和 CDK4 减少，但滋养层相关基因增加。在 OCT4 过表达的囊胚中，SOX2 和 NANOG 阳性细胞增加，而 SOX17 阳性细胞减少，囊胚的总细胞数增加。实时 PCR 分析结果表明，SOX2、NANOG 和 CDK4 的表达增加，而 SOX17 的表达减少。
综上所述，我们的结果表明，OCT4 可使猪囊胚中的多能性，并在 ICM 形成、次级细胞命运决定和细胞增殖中发挥重要作用。
