OCT4 target genes show distinctive nucleosome occupancy patterns that underlie the potential for gene expression.
(A) Genome-wide studies were performed in human embryonic stem cells (H1) using ENCODE and GEO data (wgEncodeHudsonalphaMethylSeqRegionsRep1H1hesc for DNA methylation, GSM518373 for OCT4 ChIP-Seq and wgEncodeUwDnaseSeqPeaksRep1H1es for DNaseI). The data comprised 100 bp windows of OCT4 binding regions (29740 sites), DNA methylated regions (43659 sites) and DNaseI hypersensitive regions (123778 sites). (B and E) H1 and NCCIT cells were exposed to 10 uM RA for the indicated days. The expression levels of OCT4, NANOG, PAX6 and NEUROG1 were determined by quantitative PCR (normalized to PCNA). Quantitative PCR data represent the average of three biological experiments (the mean +SEM) (C, D, F and G) Nucleosome occupancy at the PAX6 and NEUROG1 promoters was analyzed by NOMe-seq during differentiation of H1 and NCCIT cells. Blue circles represent GpC sites of the DNA (unfilled blue circles represent GpC sites which are inaccessible to GpC methyltransferase, teal-filled circles represent cytosines accessible to GpC methyltransferase). Pink bars represent regions of inaccessibility large enough to accommodate a nucleosome (around 150 bp). The data is representative of three biological experiments.