转突变型A53Tα-突触核蛋白基因的帕金森模型小鼠中脑的全基因组甲基化测序分析

Whole Genome Bisulfite Sequencing Study on Parkinson′s Disease Model Mice Genetically Modified by A53T Mutant α-Synuclein in Midbrain

[目的]研究帕金森氏病(PD)致病基因SNCA在A53T位置突变后对转基因小鼠中脑多巴胺,神经元DNA甲基化修饰的影响。[方法]分别取转突变的人源α-突触核蛋白(hα-syn)即hA53Tα-syn基因小鼠和对照组小鼠的中脑组织,采用重亚硫酸盐测序法(BS-seq)分别对12月龄的转基因小鼠和非转基因(nTg)小鼠进行全基因组甲基化分析,随后筛选出差异甲基化区域(D MR)用于GO富集分析。[结果]通过对比分析,我们总计发现481个DMR,其中高甲基化与低甲基化DMR分别有257和224个,包括与泛素降解途径相关的Ubqln2、HECTD4、Rnf157基因,丝氨酸/苏氨酸蛋白激酶PINK1等基因。富集结果显示,差异甲基化基因总共映射到545个GO子条目,且主要富集于解剖结构发育、树突发育、神经系统发育、神经元投射等条目。[结论]帕金森致病基因SNCA在A53T位置的突变可诱导小鼠中脑多巴胺神经元DNA甲基化改变。

【Objective】To investigate the effect of PD-related gene SNCA mutated in A53T on methylation modifica⁃tion in the dopaminergic neurons from the mouse midbrain.【Methods】The midbrain tissue from the A53T mutant humanα-synuclein(hA53Tα-syn)transgenic mice and non-transgenic(nTg)mice were isolatedα-synmice.Bisulfite-sequenc⁃ing(BS-seq)was utilized for analyzing the DNA methylation of 12-month-old of hA53Tα-synmice and nTg mice at a whole genome level.Subsequently,differentially methylated regions(DMRs)were screened for GO enrichment analyses.【Results】Through comparative analyses,481 DMRs were found.Among the data,hypermethylated and hypomethylated DMRs accounted for 257 and 224 respectively.These DMRs involved in ubiquitin degradation pathway-related genes,including Ubqln2,HECTD4,Rnf157 genes;serine/threonine protein kinase PINK1 gene,etc.Enrichment data re⁃vealed that the genes containing DMRs projected to 545 GO sub-terms,and significantly enriched in anatomical structure development,dendrite development,nervous system development,neuronal projection,etc.【Conclusion】The A53T mu⁃tation of SNCA gene which is related to PD could introduce DNA methylation alterations in mouse midbrain.