Epigenetic Regulation of Cell Type–Specific Expression Patterns in the Human Mammary Epithelium (original) (raw)
Figure 4
Genome-wide H3K27me3 patterns of human mammary epithelial progenitor and differentiated luminal cells.
(A) Patterns of K27 enrichment and gene expression are mutually exclusive. Representative example of K27 distribution and gene expression in chr1. Data was analyzed using SICER algorithm [28] using 10 kb as window size. Significantly enriched regions and gene expression levels are plotted as colored lines across chromosome position. Red and blue lines represent K27 enrichment in CD44+ and CD24+ cell libraries from three different individuals, respectively. Gene expression levels are plotted across chromosome position. The height of line indicates the level of expression of corresponding gene. Orange and light blue: median expression in CD44+ and CD24+ samples, respectively. (B) Representative examples showing that distinct K27 distributions correlate with gene expression using the same plot as in panel A but at different scale. Red and blue dots indicate genes highly expressed (>2 fold difference) in CD44+ and CD24+ cells, respectively. Clear differences in K27 distribution between the two cell types are observed consistently in the regions where the selected genes are located. (C) Correlations between the number of K27 blocs and the number of genes in these blocs in CD44+ (left) and CD24+ (right) cells depending on setting K27 blocs at different sizes. X-axes indicate the threshold of length for defining K27 blocs, whereas y-axes show the number of K27 blocs and the number of genes within these blocs. (D) Fraction of genes with the indicated expression pattern located within K27 blocs in CD44+ and CD24+ cells.