鸡热休克蛋白70基因启动子区CpG岛的甲基化研究

Methylation of CpG island in the promoter region of chicken heat shock protein 70 gene

为了获得鸡热休克蛋白70(heat shock protein 70,HSP70)基因启动子区CpG岛的甲基化状态,初步探索HSP70基因在肌肉组织生长发育中的作用,试验以文昌鸡和北京油鸡为试验材料,采用MassArray质谱法检测鸡胸肌中HSP70基因启动子区CpG岛的甲基化水平,比较分析文昌鸡和北京油鸡HSP70基因的甲基化差异。结果表明:在HSP70基因启动子中共检测到65个CpG位点的甲基化水平;文昌鸡胸肌生长发育过程中有8个CpG位点甲基化水平发生明显改变,其甲基化密度从第30天到第120天基本呈下降趋势;北京油鸡胸肌生长发育过程中只有3个CpG位点甲基化水平发生明显改变,其甲基化密度从第30天到第120天基本呈升高趋势,第120天时甲基化水平达到最高。说明文昌鸡与北京油鸡HSP70基因启动子区CpG岛的甲基化模式和水平不同,这可能导致两种鸡对应激反应产生不同的耐受程度。

This study aimed to investigate the promoter CpG islands methylation status of chicken heat shock protein 70 ( HSP70) gene, explore the role of HSP70 gene in muscle growth and development stages. With MassArray system, the methylation levels of CpG islands in HSP70 gene promoter were analyzed and compared in breast muscle of Wenchang chicken and Beijing-You chicken. The results showed that sixty-five CpG dinucleotides on HSP70 promoter were tested. A total of 8 CpG sites were significantly different among different developmental stages in Wenchang chicken and the trend was down-regulated from 30 days to 120 days. A total of 3 CpG sites were significantly different among different developmental stages in Beijing-You chicken and the trend was up-regulated from 30 days to 120 days, reaching their highest methylation level at 120 days. This study proves that the methylation patterns and levels of HSP70 gene in Wenchang chicken and Beijing-You chicken are different. This may lead to different levels of stress tolerance in both chickens.