Luo Lei, Dang Yanna, Shi Yan, Zhao Panpan, Zhang Yunhai, Zhang Kun
Laboratory of Mammalian Molecular Embryology, Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, School of Medicine, College of Animal Sciences, Zhejiang University, Hangzhou, China.
Anhui Provincial Laboratory of Local Livestock and Poultry Genetical Resource Conservation and Breeding, College of Animal Science and Technology, Anhui Agricultural University, Hefei, China.
Front Cell Dev Biol. 2021 Feb 22;9:604232. doi: 10.3389/fcell.2021.604232. eCollection 2021.
SIN3A is the central scaffold protein of the SIN3/histone deacetylase (HDAC) transcriptional repressor complex. SIN3A participates in the mouse preimplantation development by fine-tuning expression. However, it remains unresolved if this functional significance of SIN3A was conserved in other mammals. Herein, RNA-seq results show a large amount of mRNA is present in oocytes and early embryos prior to embryonic genome activation and a low amount thereafter, suggesting a maternal origin of SIN3A in pigs, cattle, mice, and humans. Interestingly, immunofluorescence data show that SIN3A protein level peaks at four-cell stage in pigs compared with morula stage in cattle. SIN3A depletion in early embryos causes a developmental arrest at two-cell stage in pigs but does not affect bovine early embryonic development. In contrast with mouse data, SIN3A depletion results in only a slight decrease and even no difference in HDAC1 expression in porcine and bovine early embryos, respectively. In addition, HDAC1 knockdown does not cause two-cell block but leads to a reduced blastocyst rate. By using unbiased RNA-seq approach, we found that () transcript level is dramatically reduced. Moreover, CCNB1 knockdown results in a similar phenotype as SIN3A depletion. Injection of exogenous mRNA into SIN3A-depleted embryos could partly rescue embryonic development to pass two-cell stage. In conclusion, our results indicate SIN3A plays an essential role in porcine early embryonic development, which probably involves the regulation of expression.
SIN3A是SIN3/组蛋白去乙酰化酶（HDAC）转录抑制复合物的核心支架蛋白。SIN3A通过微调表达参与小鼠植入前发育。然而，SIN3A的这种功能重要性在其他哺乳动物中是否保守仍未得到解决。在此，RNA测序结果显示，在胚胎基因组激活之前，卵母细胞和早期胚胎中存在大量mRNA，之后含量较低，这表明猪、牛、小鼠和人类中SIN3A来源于母体。有趣的是，免疫荧光数据显示，与牛的桑椹胚阶段相比，猪的SIN3A蛋白水平在四细胞阶段达到峰值。早期胚胎中SIN3A的缺失导致猪在二细胞阶段发育停滞，但不影响牛的早期胚胎发育。与小鼠数据相反，SIN3A的缺失分别导致猪和牛早期胚胎中HDAC1表达仅略有下降甚至没有差异。此外，HDAC1的敲低不会导致二细胞阻滞，但会导致囊胚率降低。通过使用无偏RNA测序方法，我们发现（）转录水平显著降低。此外，CCNB1的敲低导致与SIN3A缺失相似的表型。将外源性mRNA注射到SIN3A缺失的胚胎中可以部分挽救胚胎发育，使其通过二细胞阶段。总之，我们的结果表明SIN3A在猪早期胚胎发育中起重要作用，这可能涉及对（）表达的调节。
