Li Junliang, Chen Weina, Li Dongjie, Gu Shukai, Liu Xiaoqian, Dong Yanqiu, Jin Lanjie, Zhang Cui, Li Shijie
College of Life Science, Agricultural University of Hebei, Baoding 071000, China.
Department of Traditional Chinese Medicine, Hebei University, Baoding 071000, China.
Animals (Basel). 2021 Jul 2;11(7):1985. doi: 10.3390/ani11071985.
Genomic imprinting is the epigenetic mechanism of transcriptional regulation that involves differential DNA methylation modification. Comparative analysis of imprinted genes between species can help us to investigate the biological significance and regulatory mechanisms of genomic imprinting. , and are three maternally imprinted genes identified in the human PWS/AS imprinted locus. This study aimed to assess the allelic expression of , and and to examine the differentially methylated regions (DMRs) of bovine PWS/AS imprinted domains. An expressed single-nucleotide polymorphism (SNP)-based approach was used to investigate the allelic expression of , and genes in bovine adult tissues and placenta. Consistent with the expression in humans and mice, we found that the , and genes exhibit monoallelic expression in bovine somatic tissues and the paternal allele expressed in the bovine placenta. Three DMRs, PWS-IC, and DMR, were identified in the bovine imprinted region by analysis of the DNA methylation status in bovine tissues using the bisulfite sequencing method and were located in the promoter and exon 1 of the gene, promoter and 5' untranslated region (5'UTR) of gene, respectively. The PWS-IC DMR is a primary DMR inherited from the male or female gamete, but and DMR are secondary DMRs that occurred after fertilization by examining the methylation status in gametes.
基因组印记是一种涉及DNA甲基化差异修饰的转录调控表观遗传机制。对不同物种间印记基因进行比较分析有助于我们探究基因组印记的生物学意义和调控机制。SNRPN、UBE3A和NDN是在人类普拉德-威利综合征/安吉尔曼综合征（PWS/AS）印记基因座中鉴定出的三个母源印记基因。本研究旨在评估SNRPN、UBE3A和NDN的等位基因表达，并检测牛PWS/AS印记区域的差异甲基化区域（DMR）。采用基于单核苷酸多态性（SNP）表达的方法研究SNRPN、UBE3A和NDN基因在牛成年组织和胎盘中的等位基因表达。与在人类和小鼠中的表达情况一致，我们发现SNRPN、UBE3A和NDN基因在牛体细胞组织中呈现单等位基因表达，且父源等位基因在牛胎盘中表达。通过亚硫酸氢盐测序法分析牛组织中的DNA甲基化状态，在牛SNRPN印记区域鉴定出三个DMR，即PWS-IC、UBE3A DMR和NDN DMR，它们分别位于SNRPN基因的启动子和外显子1、UBE3A基因的启动子和5'非翻译区（5'UTR）。通过检测配子中的甲基化状态发现，PWS-IC DMR是一个从雄配子或雌配子遗传而来的主要DMR，而UBE3A DMR和NDN DMR是受精后出现的次要DMR。
