甲基化测序分析流程
对参考基因组和reads进行预处理
-将C全部替换为T
-将序列反向互补,G替换为A将预处理后的reads比对到参考基因组,比对结果中序列信息为原始reads(即未进行C转T的reads)
甲基化位点
CpG
CpHpG
CHH(H=A,T,G)-
甲基化区域与功能
- 启动子区域 -- 抑制基因表达
- 动植物中活跃转录的基因CpG甲基化程度升高
- CpHpG通常存在于植物中不表达的转座子内
甲基化测序策略 -- BS-Seq
- WGBS
价格较高,Raw-data 数据量庞大,增加分析难度
- RRBS
WGBS的替代方法
This technique combines restriction enzymes and bisulfite sequencing in order to
enrich for the areas of the genome that have a high CpG content. Due to the high cost
and depth of sequencing needed to analyze methylation status in the entire genome,
Meissner et al. developed this technique in 2005 in order to reduce the amount of
nucleotides needed to be sequenced to 1% of the genome.