Improvement in the in vitro development of cloned pig embryos after kdm4a overexpression and an H3K9me3 methyltransferase inhibitor treatment
Improvement in the in vitro development of cloned pig embryos after kdm4a overexpression and an H3K9me3 methyltransferase inhibitor treatment
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kdm4a 过表达和 H3K9me3 甲基转移酶抑制剂处理后克隆猪胚胎体外发育的改善
DOI：
10.1016/j.theriogenology.2019.11.027
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发表时间：
2019
期刊：
影响因子：
2.8
通讯作者：
Zhonghua Liu
中科院分区：
文献类型：
--
作者：
Xiaogang Weng;Mingming Cai;Yuting Zhang;Yan Liu;Cong Liu;Zhonghua Liu
异常的表观遗传重编程是体细胞核移植（SCNT）后胚胎发育失败的主要原因。组蛋白H3赖氨酸9三甲基化（H3 K9 me 3），转录抑制的组蛋白标记，被认为是克隆胚胎发育的关键障碍。在本研究中，在4-细胞和2-细胞阶段，SCNT胚胎中的H3 K9 me 3水平远高于IVF胚胎。显微注射编码H3 K9 me 3去甲基化酶的kdm 4a mRNA显著提高了克隆猪胚胎的发育效率。此外，我们评估了毛壳素，组蛋白甲基转移酶suv 39 h1/2的抑制剂，对SCNT胚胎发育的影响。在猪胚胎成纤维细胞（PEF）中，毛壳素不能抑制H3 K9 me 3的修饰，但能下调suv 39 h1、suv 39 h2和kdm 4d的表达。然而，10 nM毛壳素处理有效地降低了克隆胚胎中的H3 K9 me 3水平。重要的是，在4-细胞阶段的毛壳素处理6小时显著增加了胚泡率和总细胞数。此外，抑制剂处理上调相关发育基因的表达。总之，kdm 4a的过表达和suv 39 h1/2抑制剂的处理都改善了克隆胚胎的表观遗传重编程，并进一步改善了体外发育能力。
Aberrant epigenetic reprogramming is a major cause of the developmental failure of embryos after somatic cell nuclear transfer (SCNT). Histone H3 lysine 9 trimethylation (H3K9me3), a histone marker of transcriptional repression, is considered a key barrier to the development of cloned embryos. In the present study, H3K9me3 levels were much higher in SCNT embryos than IVF embryos at the 4-cell and 2-cell stages. The microinjection of the kdm4a mRNA encoding an H3K9me3 demethylase significantly increased the developmental efficiency of cloned porcine embryos. Moreover, we evaluated the effect of chaetocin, an inhibitor of histone methyltransferases suv39h1/2, on SCNT embryo development. Chaetocin did not suppress the H3K9me3 modification in porcine embryonic fibroblast (PEF) but downregulated the expression of suv39h1, suv39h2, and kdm4d. However, 10 nM chaetocin treatment efficiently decreased the H3K9me3 level in cloned embryos. Importantly, a chaetocin treatment at the 4-cell stage for 6 hours significantly increased the blastocyst rate and total cell numbers. Furthermore, the inhibitor treatment upregulated the expression of related developmental genes. In summary, both overexpression of kdm4a and treatment with a suv39h1/2 inhibitor improve the epigenetic reprogramming of cloned embryos and further improve the developmental competence in vitro.