H3K9me3 controls epidermis morphogenesis by regulating RNA Pol II dynamics at developmental promoters and enhancers (opens in new tab)

Histone H3K9me3 silences repetitive elements and represses non-lineage genes during early development, but its role in organogenesis is understudied. Here, we show that H3K9me3 deposition is dynamic during epidermis morphogenesis and essential for lineage diversification. We ablate Suv39h1, Suv39h2, and Setdb1 histone methyltransferases, in the embryonic mouse epidermis, to induce H3K9me3 loss. This causes complete failure of keratinocyte differentiation, skin barrier formation, hair follicle...