Suppressor of variegation 3–9 homolog (Suv39h)1 and 2, Histone H3 lysine 9 trimethylation (H3K9me3)-specific methyltransferases, are mainly involved in regulating the dynamic changes of H3K9me3. Regulating Suv39h expression influences the early development of mice somatic cell nuclear transfer (SCNT) embryos, there are few reports concerning their features in domestic animals. The aim of the present study was to characterize the Suv39h function in early development of Debao porcine SCNT embryos. The global level of H3K9me3 and the expression profiles of Suv39h1/2 in porcine early embryos were analysed by immunohistochemistry and qRT-PCR methods, respectively. Their roles in cell proliferation and histone modification of Debao porcine foetal fibroblast cells (PFFs), and developmental competence of porcine SCNT embryos were investigated by shRNA technology. The methylation levels of H3K9me3 and the expression patterns of Suv39h1 and Suv39h2 were similar (p < .05), and both of them displayed higher levels in Debao porcine SCNT embryos compared with that in PA embryos. The global levels of H3K9me3 and the expressions of G9a, HDAC1 and DNMT1 were decreased by combined inhibition of Suv39h1 and Suv39h2 (p < .05), while the expression of HAT1 was increased (p < .05). Downregulation of Suv39h1/2 also promoted cell proliferation and resulted in a significant increase in the expression of CyclinA2, CyclinB and PCNA in PFFs (p < .05). Furthermore, the use of donor somatic nuclei which depleted H3K9me3 by inhibiting Suv39h1/2 expression markedly increased the cleavage rate, the blastocyst rate and the total cell number of blastocysts of Debao porcine SCNT embryos (p < .05). Altogether, the above results indicate that H3K9me3 levels and Suv39h1/2 expressions display similar patterns in porcine early embryo, and low levels of them are critical to cell proliferation of PFFs and early development of SCNT embryos.

中文翻译：

---

抑制Suv39h1/2表达改善德宝猪体细胞核移植胚胎早期发育

杂色抑制因子 3-9 同源物 (Suv39h)1 和 2，组蛋白 H3 赖氨酸 9 三甲基化 (H3K9me3) 特异性甲基转移酶，主要参与调节 H3K9me3 的动态变化。调节Suv39h表达影响小鼠体细胞核移植 (SCNT) 胚胎的早期发育，关于其在家畜中的特征的报道很少。本研究的目的是表征德宝猪 SCNT 胚胎早期发育中的Suv39h功能。H3K9me3的全局水平和Suv39h1/2的表达谱分别通过免疫组织化学和 qRT-PCR 方法分析了猪早期胚胎中的 通过shRNA技术研究了它们在德宝猪胎儿成纤维细胞（PFFs）的细胞增殖和组蛋白修饰中的作用，以及猪SCNT胚胎的发育能力。H3K9me3 的甲基化水平以及Suv39h1 和 Suv39h2的表达模式相似（p  < .05），并且与 PA 胚胎相比，它们在德宝猪 SCNT 胚胎中的甲基化水平更高。联合抑制Suv39h1和Suv39h2可降低H3K9me3的整体水平以及G9a、HDAC1和DNMT1的表达（p < .05），而HAT1的表达增加（p  < .05）。Suv39h1/2 的下调也促进了细胞增殖并导致PFF 中 CyclinA2、CyclinB和PCNA的表达显着增加( p  < .05)。此外，使用通过抑制Suv39h1/2表达耗尽 H3K9me3 的供体体细胞核显着增加了德宝猪 SCNT 胚胎的卵裂率、囊胚率和囊胚总细胞数 ( p  < .05)。综上所述，上述结果表明 H3K9me3 水平和Suv39h1/2 表达在猪早期胚胎中显示出相似的模式，它们的低水平对 PFF 的细胞增殖和 SCNT 胚胎的早期发育至关重要。