Fig. 2

Comparison of methylation between lens and non-lens cells at the Nanog, Pou5f1, and Sox2 loci encoding the core pluripotency GRN in the ES cells. A Nanog locus. We marked ~ 8 kb region of demethylation, including both the distal and proximal promoter regions and extending into the 5′-portion of intron 2 in ES cells (boxed). Gain of methylation in other cell types is also shown (dotted boxes). B Pou5f1 locus. We marked ~ 6.5 kb of demethylated/low-methylated DNA that includes 5′-promoter flanking region extending towards intron 4 in ES cells (boxed). Major gain of DNA methylation is found in other samples (boxed). C Sox2 locus. We show ~ 60 kb of Sox2 locus as this region contains multiple distal enhancers active during chicken lens placode formation [60]. Note that low methylation region (~ 8 kb) include upstream region of its promoter and the entire coding region of the Sox2 locus