与绝经年龄相关的差异甲基化位点筛选及其与抑郁关联基因的初步分析

Screening of menopausal age-related differential methylation sites and its association with depression

目的应用基因甲基化芯片技术筛选脂肪组织与绝经年龄相关的甲基化位点,并分析其中可能与绝经年龄相关抑郁的差异甲基化基因的功能。方法应用甲基化450K芯片对早绝经组和晚绝经组人体脂肪组织基因组DNA进行甲基化分析,筛选出异常甲基化位点,按甲基化β值差值区分高甲基化低甲基化、位点;进一步对抑郁相关差异甲基化位点行生物信息学分析,初步了解其相关功能。结果共检出早绝经组、晚绝经组的差异明显甲基化位点415个,其中高甲基化位点169个,低甲基化位点共246个。在前40位差异明显的基因中,6号染色体有11个差异化位点,1号染色体有10个差异化位点,11号染色体有7个差异化位点。GO和KEGG分析显示,与抑郁相关的高甲基化3个基因包括脑源性神经生长因子(BDNF)、钙离子通道的α1C亚单位基因(CACNA1C)以及Rho鸟嘌呤核苷酸交换因子(ARHGEF10)可能与DNA结合、转录因子活性、信号转导通路等有关。蛋白质网络结构图可见,BDNF分别参与神经生长、营养、调控细胞增殖和凋亡等功能。ARHGEF10主要作用蛋白为WDR48,该蛋白与泛素特异性肽酶1(USP1)相互作用,激活USP1的去泛素活性。CACNA1C主要参与肌肉收缩、激素或神经递质释放、基因表达、细胞运动、细胞分裂和细胞死亡等生物学过程。结论早绝经组与晚绝经组存在大量差异甲基化位点,其中BDNF、ARHGEF10及CACNA1C甲基化异常可能与女性绝经年龄相关抑郁有关,它们的主要功能可能与DNA结合、转录因子活性、信号转导通路等有关。基因芯片技术可用于抑郁相关甲基化差异甲基化位点的初筛,但构建抑郁关联差异甲基化谱作为临床分子标记物仍需行进一步验证。

Objective To screen the menopausal age-related differential methylation sites by the gene methylation chip technology,and analyze the function of differentially methylated genes that may be associated with menopausal agerelated depression.Methods The methylation 450K chip was used for methylation analysis of human adipose tissue genomic DNA in early menopause and late menopause,and abnormal methylation sites were screened out,and hypermethylation and low methylation sites were distinguished by the difference of methylationβvalue.The further bioinformatics analysis of depression-related differential methylation sites was carried out.Results A total of 415 methylation sites with significant differences between early and late menopause groups were detected,including 169 hypermethylated sites and 246 hypomethylation sites.Among the top 40 genes with significant differences,11 differential sites were on chromosome 6,10 differential sites on chromosome 1,and 7 differential sites on chromosome 11.The GO and KEGG analysis showed that 3 significant hypermethylation genes(BDNF,CACNA1C,and ARHGEF10)may be related to DNA binding,transcription factor activity,and signal transduction pathways.The protein network structure diagram showed that BDNF were involved in nerve growth,nutrition,regulation of cell proliferation and apoptosis.ARHGEF10 interacted with ubiquitin-specific peptidase 1(USP1)to activate the deubiquitin activity of USP1.CACNA1C were mainly involved in the biological processes of muscle contraction,hormone or neurotransmitter release,gene expression,cell movement,cell division and cell death.Conclusion A large number of differentially methylated sites exist in the early and late menopause groups.Among them,abnormal methylation of BDNF,ARHGEF10 and CACNA1C may be related to the menopausal age-related depression,whose main functions may be related to DNA binding,transcription factor activity,and signal transduction pathways.Gene chip technology can be used for the preliminary screening of depression-related differential methylation sites,and it is need to further verify that the construction of depression differential methylation profiles can be as the clinical molecular markers.