中国生物工程杂志

Hypermethylation of CpG islands is an epigenetic modification and plays key role in tumorigenesis . Several methods for methyl-CpG islands detection have been established , but high through methyl-CpG islands enrich method for whole genome was not reported till now. In this study we reported a rapid and efficient genome-wide methylation enrichment method which is based on DNA immunoprecipitation for accumulating methyl-CpG islands .The GST-MBD2b recombinant protein was expressed in E.Coli and purified by using Glutatione Sepharose 4B. The methylated CpG islands was enriched by the GST-MBD2b affinity column which has the capability to bind methylated CpG islands at high salt concentration. The enrich efficiency was detected by real time PCR and the results indicated that the methylated CpG islands was enriched more than 100 folds. The enriched methylated CpG islands could be used further experiments for example real time quantitative PCR, DNA sequencing and whole genome CpG islands microarray analysis.