奶牛乳腺组织RPS6KB1基因启动子甲基化分析

DNA甲基化是目前生命科学领域的研究热点之一，DNA甲基化在维持细胞功能、遗传印记、个体生长发育中起着重要作用．本研究采用亚硫酸氢盐测序(BSP)技术检测了不同发育时期奶牛乳腺组织及不同乳品质泌乳期奶牛乳腺组织RPS6KB1启动子的甲基化特征，实时荧光定量PCR检测RPS6KB1基因mRNA差异表达．实验结果显示，在RPS6KB1基因启动子内存在CpG及非CpG的甲基化模式，其中泌乳期奶牛之间甲基化水平相似，妊娠期奶牛甲基化程度高于泌乳期奶牛．荧光定量结果显示不同发育时期，RPS6KB1基因mRNA水平表达差异显著（P<0.05），而两组泌乳期奶牛之间差异不显著（P>0.05）.说明RPS6KB1的表达受到其启动子甲基化的调控，非CpG甲基化模式可能具有与CpG甲基化模式相似的生物学功能，参与RPS6KB1的表达调控．

Methylation Analysis of RPS6KB1 Promoter in Bovine Mammary Tissue

The DNA methylation is a focus of the life science for its important roles in maintaining cell function, genetic imprinting, individual growth and development. This study used bisulphite sequencing (BSP) technique to detect the methylation of RPS6KB1 promoter in cows at different developmental stage and with different dairy quality. We also detected the RPS6KB1 mRNA expression by real-time quantitative PCR (qT-PCR). The results showed that the CpG and non CpG methylation patterns in the RPS6KB1 promoter were similar in lactation mammary tissue, which was lower than that in pregnancy. The RPS6KB1 expression was significantly different（P<0.05）among different development stages, but not in lactation cows with different dairy qualities．These results indicated that the expression of RPS6KB1 was influenced by the methylation of its promoter．The CpG and non-CpG methylation might contribute similarly for the biological function in regulating RPS6KB1 expression.