In embryonic stem (ES) cells. bivalent chromatin domains with overlapping repressive (H3 lysine 27 tri-methylation) and activating (H3 lysine 4 tri-methylation) histone modifications mark the promoters of more than 2. 000 genes. To gain insight into the structure and function of bivalent domains. https://spencertifieders.shop/product-category/musical-instrument-amplifier-accessories/