Bivalent Promoters in fNSCs and BTSCs. A. H3K4me3+/H3K27me3+ promoter in fNSCs and B73 cells. Note that both marks are in the proximal promoter but show little overlap. This was the most common pattern. Left axes are log2 enrichment ratio. B. Two patterns for H3K4me3+/H3K9me3+ promoters (B12 cells). (left) Non-overlapping marks in proximal promoter. This is the most common pattern. (right) Overlapping marks. Left axes are log2 enrichment ratio. C. (left) H3K4me3+/H3K27me3+ promoter counts in each cell line and the number shared with fNSCs. (right) H3K4me3+/H3K9me3+ promoters in each cell line and number shared with fNSCs. ALL refers to bivalent promoters found in all 5 cell types. LOST refers to promoters that are bivalent in fNSCs and lack both marks in every BTSC line. D. Examples of fNSC H3K4me3+/H3K27me3+ promoters that resolve to either H3K27me3+ (left) or H3K4me3+ (right) promoters in the B73 line. Left axes are log2 enrichment ratio. Markings: For A, B, and D, transcripts are shown with arrows and line drawing. All displayed transcripts extend beyond edges of panel in figure. Markings for top axes (genomic coordinate of first tick mark (increment to next tick mark)): A: chr17:33,063,000 (3 kb); B: left: chr3:114,711,000 (1 kb); right: chr19:62,812,000 (1 kb); D: left: chr9:23,790,000 (6 kb); right: chr9:68,541,000 (3 kb).