Dynamics of chromatin accessibility during TGF-beta-induced EMT of Ras-transformed mammary gland epithelial cells. Dynamics of chromatin accessibility during TGF-beta-induced EMT of Ras-transformed mammary gland epithelial cells

This SuperSeries is composed of the SubSeries listed below. Epithelial-mesenchymal transition (EMT) is induced by transforming growth factor (TGF)-beta stimulation and facilitates tumor progression. We here performed global mapping of accessible chromatin in the mouse mammary gland epithelial EpH4 cell line and its Ras-transformed derivative (EpRas) using formaldehyde-assisted isolation of regulatory element (FAIRE)-sequencing (seq). We also searched for differentially expressed transcription factors by RNA-seq and found that Etv4, an ETS family oncogenic transcription factor, was strongly expressed in EpRas cells. Moreover, chromatin immunoprecipitation (ChIP)-seq showed that Etv4 bound to more than one-third of the accessible chromatin regions in EpRas cells treated with TGF-beta. We found by gene ontology analysis that genes encoding extracellular proteins are the most strongly down-regulated genes by Etv4 and Etv5 siRNAs. These findings suggest a mechanism of transcriptional regulation during TGF-beta-induced EMT that involves alterations of accessible chromatin. Overall design: Refer to individual Series