College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling Shaanxi, China.
Institute of Cellular and Molecular Biology, Jiangsu Normal University, Xuzhou Jiangsu, China.
Gene. 2014 Jan 25;534(2):356-61. doi: 10.1016/j.gene.2013.09.111. Epub 2013 Oct 16.
DNA methylation is a key epigenetic modification in mammals and has an essential and important role in muscle development. Insulin-like growth factor 2 (IGF2) is a fetal growth and differentiation factor that plays an important role in muscle growth and in myoblast proliferation and differentiation. The aim of this study was to evaluate the expression of IGF2 and the methylation pattern on the differentially methylated region (DMR) of the last exon of IGF2 in six tissues with two different developmental stages. The DNA methylation pattern was compared using bisulfite sequencing polymerase chain reaction (BSP) and combined bisulfite restriction analysis (COBRA). The quantitative real-time PCR (qPCR) analysis indicated that IGF2 has a broad tissue distribution and the adult bovine group showed significant lower mRNA expression levels than that in the fetal bovine group (P<0.05 or P<0.01). Moreover, the DNA methylation level analysis showed that the adult bovine group exhibited a significantly higher DNA methylation levels than that in the fetal bovine group (P<0.05 or P<0.01). These results indicate that IGF2 expression levels were negatively associated with the methylation status of the IGF2 DMR during the two developmental stages. Our results suggest that the methylation pattern in this DMR may be a useful parameter to investigate as a marker-assisted selection for muscle developmental in beef cattle breeding program and as a model for studies in other species.
DNA 甲基化是哺乳动物中一种重要的表观遗传修饰，在肌肉发育中具有重要作用。胰岛素样生长因子 2（IGF2）是一种胎儿生长和分化因子，在肌肉生长以及成肌细胞增殖和分化中发挥重要作用。本研究旨在评估 IGF2 的表达以及 IGF2 最后一个外显子上差异甲基化区域（DMR）的甲基化模式在两个不同发育阶段的六种组织中的变化。采用亚硫酸氢盐测序聚合酶链反应（BSP）和联合亚硫酸氢盐限制性分析（COBRA）比较 DNA 甲基化模式。定量实时 PCR（qPCR）分析表明，IGF2 具有广泛的组织分布，成年牛组的 mRNA 表达水平明显低于胎儿牛组（P<0.05 或 P<0.01）。此外，DNA 甲基化水平分析表明，成年牛组的 DNA 甲基化水平明显高于胎儿牛组（P<0.05 或 P<0.01）。这些结果表明，在两个发育阶段，IGF2 的表达水平与 IGF2 DMR 的甲基化状态呈负相关。我们的研究结果表明，该 DMR 中的甲基化模式可能是一个有用的参数，可以作为肉牛肌肉发育的标记辅助选择研究，也可以作为其他物种研究的模型。
