Shao Weini, Ning Wei, Liu Chang, Zou Yuanyuan, Yao Yurui, Kang Jiaxin, Cao Zubing
Anhui Province Key Laboratory of Local Livestock and Poultry, Genetical Resource Conservation and Breeding, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, China.
Animals (Basel). 2022 Aug 29;12(17):2226. doi: 10.3390/ani12172226.
SET domain-containing 2 (SETD2) is a methyltransferase that can catalyze the di- and tri-methylation of lysine 36 on histone H3 (H3K36me2/me3). SETD2 frequently mediates H3K36me3 modification to regulate both oocyte maturation and preimplantation embryonic development in mice. However, the specific substrate and function of SETD2 in porcine early embryonic development are still unclear. In this study, SETD2 preferentially catalyzed H3K36me3 to regulate porcine early embryonic development. SETD2 mRNA is dynamically expressed during early embryonic development. Functional studies using an RNA interference (RNAi) approach revealed that the expression levels of SETD2 mRNA were effectively knocked down by siRNA microinjection. Immunofluorescence analysis indicated that knockdown (KD) did not affect H3K36me2 modification but significantly reduced H3K36me3 levels, suggesting a preferential H3K36me3 recognition of SETD2 in porcine embryos. Furthermore, KD significantly reduced blastocyst rate and disrupted allocation between inner cell mass (ICM) and trophectoderm (TE) lineage. The expression levels of key genes important for specification of the first two lineages apparently decreased in KD blastocysts. KD markedly increased the apoptotic percentage of cells within embryos and altered the expression of pro- and anti-apoptotic genes. Therefore, our data indicate that SETD2 is essential for porcine early embryonic development.
含SET结构域蛋白2（SETD2）是一种甲基转移酶，可催化组蛋白H3赖氨酸36位点的二甲基化和三甲基化（H3K36me2/me3）。SETD2常介导H3K36me3修饰以调控小鼠卵母细胞成熟和植入前胚胎发育。然而，SETD2在猪早期胚胎发育中的具体底物和功能仍不清楚。在本研究中，SETD2优先催化H3K36me3以调控猪早期胚胎发育。SETD2 mRNA在早期胚胎发育过程中动态表达。使用RNA干扰（RNAi）方法的功能研究表明，通过显微注射siRNA可有效降低SETD2 mRNA的表达水平。免疫荧光分析表明，敲低（KD）不影响H3K36me2修饰，但显著降低H3K36me3水平，这表明SETD2在猪胚胎中优先识别H3K36me3。此外，KD显著降低囊胚率，并破坏内细胞团（ICM）和滋养外胚层（TE）谱系之间的分配。在KD囊胚中，对前两个谱系特化重要的关键基因的表达水平明显降低。KD显著增加胚胎内细胞的凋亡百分比，并改变促凋亡和抗凋亡基因的表达。因此，我们的数据表明SETD2对猪早期胚胎发育至关重要。
