Abstract:
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. MKRN3, MAGEL2 and NDN are three maternally imprinted genes identified in the human PWS/AS imprinted locus. This study aimed to assess the allelic expression of MKRN3, MAGEL2 and NDN 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 MKRN3, MAGEL2 and NDN genes in bovine adult tissues and placenta. Consistent with the expression in humans and mice, we found that the MKRN3, MAGEL2 and NDN genes exhibit monoallelic expression in bovine somatic tissues and the paternal allele expressed in the bovine placenta. Three DMRs, PWS-IC, MKRN3 and NDN DMR, were identified in the bovine PWS/AS 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 SNRPN gene, NDN promoter and 5\' untranslated region (5\'UTR) of MKRN3 gene, respectively. The PWS-IC DMR is a primary DMR inherited from the male or female gamete, but NDN and MKRN3 DMR are secondary DMRs that occurred after fertilization by examining the methylation status in gametes.
摘要:
基因组印记是涉及差异DNA甲基化修饰的转录调控的表观遗传机制。物种之间印迹基因的比较分析可以帮助我们研究基因组印迹的生物学意义和调控机制。MKRN3、MAGEL2和NDN是在人PWS/AS印迹基因座中鉴定的三个母系印迹基因。本研究旨在评估MKRN3,MAGEL2和NDN的等位基因表达,并检查牛PWS/AS印迹域的差异甲基化区(DMRs)。基于表达的单核苷酸多态性(SNP)的方法用于研究牛成年组织和胎盘中MKRN3,MAGEL2和NDN基因的等位基因表达。与人类和小鼠中的表达一致,我们发现MKRN3,MAGEL2和NDN基因在牛体细胞组织中表现出单等位基因表达,而父系等位基因在牛胎盘中表达。三个DMRs,PWS-IC,MKRN3和NDNDMR,通过使用亚硫酸氢盐测序方法分析牛组织中的DNA甲基化状态,在牛PWS/AS印迹区中鉴定,并位于SNRPN基因的启动子和外显子1中,NDN启动子和MKRN3基因的5'非翻译区(5'UTR),分别。PWS-ICDMR是从雄性或雌性配子遗传的主要DMR,但是NDN和MKRN3DMR是通过检查配子中的甲基化状态而在受精后发生的继发性DMR。