Chromatin aberration triggered by environmental cues

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Megabase-sized H3K9me3 domains can be triggered by environmental cues (Type I-III). These domains are prominent in primary cultured cells, and likely reflect nuclear architecture changes. They are gene-poor regions that contact the nuclear lamina in certain cells. The knock-down of histone methyltransferase Suv39h1 and the inhibitions of TGF-β decrease H3K9me3 signals in most of domains. Epithelial-to-mesenchymal transition (EMT) modestly increases the expression of genes within the domains. These culture-specific H3K9me3 domains correlate to nuclear architecture aberrations, and have implications for cellular senescence and reprogramming.