Effects of XPC overexpression on global methylation

The study examines the impact of XPC overexpression on DNA demethylation in human dermal fibroblasts (HDFs) and during the early phase of somatic cell reprogramming (pre-iPSCs). We profiled the 5mC status in wild type and XPC gain-of-function HDFs and pre-iPSCs on a genome-wide scale by MeDIP-seq. XPC overexpression results in a loss of DNA methylation in both HDFs and pre-iPSCs. In XPC gain-of-function cells, not only does DNA methylation occur in fewer regions compared to control WT cells, but overall methylation levels are lower than in WT cells. MeDIP-seq of wild type and XPC-overexpressing HDFs and pre-iPSCs (7 days into reprogramming). We prepared libraries from each MeDIP input as a control. No sample DNA was recovered for IgG IPs, indicating very little background binding was occurring.