DNA methylation in the arcuate nucleus of heifers under two nutritional schedules. Bos taurus

DNA methylation was assessed in genomic DNA obtained from the arcuate nucleus of heifers fed to gain body weight at high (HG, n = 4) and low (LG, n = 4) rates from 4.5 to 8.5 mo of age. A methyl-CpG binding domain-based (MBD) protein assay was performed to capture fragments of methylated DNA (methylated-enriched DNA). Input (total) and methylated-enriched DNA were labeled with two different dyes and co-hybridized to a custom-designed oligonucleotide array targeted to genes associated with nutritional inputs and the control of puberty. The ratio of the log2 (enriched/input) of the normalized intensities, were determined. Data was analyzed comparing values of HG versus LG heifers. Overall design: Two nutritional schedules: HG (n=4 heifers) and LG (n=4 heifers); one array per heifer; methylated enriched DNA (enriched) and total DNA (input) co-hybridyzed into each array Methylated-enriched DNA obtained from a methyl-CpG binding domain-based (MBD) protein assay

本研究对4.5至8.5月龄期间，以高增重速率（HG，n=4）和低增重速率（LG，n=4）饲养的青年母牛弓状核提取的基因组DNA进行DNA甲基化检测。采用基于甲基-CpG结合域（methyl-CpG binding domain, MBD）的蛋白捕获法，富集甲基化DNA片段（甲基化富集DNA）。将输入样本（总DNA）与甲基化富集DNA分别用两种不同荧光染料标记后，共同杂交至定制寡核苷酸微阵列，该微阵列靶向与营养摄入及青春期调控相关的基因。随后计算归一化强度的log2(富集/输入)比值。数据分析以比较HG组与LG组青年母牛的相关检测数值展开。总体实验设计：设置两种饲养方案，即高增重组（HG，n=4头青年母牛）与低增重组（LG，n=4头青年母牛）；每头青年母牛对应一张微阵列；每张阵列均共杂交甲基化富集DNA（富集样本）与总DNA（输入样本）。甲基化富集DNA通过基于甲基-CpG结合域（MBD）的蛋白捕获法获得。