IgA肾病患者CpG岛组蛋白H3赖氨酸4三甲基化水平的研究

CpG array analysis of histone H3 lysine 4 trimethylation in patients with IgA nephropathy

目的研究IgA肾病患者CpG岛组蛋白H3赖氨酸4三甲基化(H3K4me3)水平。方法采用染色质免疫共沉淀联合芯片技术(ChIP-chip)对15例IgA肾病患者和15例健康者的外周血单个核细胞(PBMCs)H3K4me3进行高通量的筛选,染色质免疫共沉淀-实时定量聚合酶链反应(ChIP-qPCR)验证芯片结果。定量反转录聚合酶链反应(qRT-PCR)检测H3K4me3显著差异基因的mRNA表达水平。结果与健康对照组相比,IgA肾病患者的83个基因存在H3K4me3显著差异,其中有39个基因显示H3K4me3水平增高,44个基因H3K4me3水平降低;ChIP-qPCR验证结果与CpG岛芯片结果相符,基因H3K4me3异常变化影响mRNA的表达。结论 IgA肾病患者PBMCs基因组H3K4me3存在显著改变,异常基因有助于研究IgA肾病的发病机制。

Objective To investigate the aberrance of histone H3 lysine 4 trimethylation（H3K4me3） in patients with IgA nephropathy（IgAN）.Methods In 15 patients with IgAN and 15 healthy volunteers,H3K4me3 variations in peripheral blood mononuclear cells（PBMCs） were analyzed using chromatin immunoprecipitation and microarray analysis（ChIP-chip）.ChIP real-time PCR was used to validate the microarray results.Quantitative real-time PCR（qRT-PCR） was carried out to examine the correlations between the mRNA expression profiles and H3K4me3 levels.Results We identified 83 genes that displayed significant H3K4me3 differences in IgAN patients compared with healthy subjects.Among them,39 genes showed increased H3K4me3 and 44 genes had decreased H3K4me3 levels.The results of ChIP real-time PCR were well consistent with the microarray data.Quantitative RT-PCR revealed the correlations between the mRNA expressions and the methylation levels of H3K4me3.Conclusion IgAN patients have significant alterations in H3K4me3,and the genes with aberrant H3K4me3 may provide insights into the pathogenesis of IgAN.