Transcription factor p63 bookmarks genomic loci in epithelial cells and regulates a subset of target genes during epidermal differentiation through dynamic enhancers (RNA-Seq)

Tightly controlled gene expression orchestrated by the transcription factor p63 during epithelial differentiation is important for development of epithelial-related structures such as epidermis, limb and craniofacial regions. How p63 regulates spatial and temporal expression of its target genes during these developmental processes is however not yet clear. By epigenomics profiling in stem cells established from one of these epithelial structures, the epidermis, we provide a global map of p63-bound regulatory elements that are categorized as single enhancers and clustered enhancers during epidermal differentiation. Transcriptomics analysis shows dynamic gene expression patterns during epidermal differentiation that correlates with the activity of p63-bound enhancers rather than with p63 binding itself. Only a subset of p63-bound enhancers is active in epidermal stem cells, and inactive p63-bound enhancers appear to function in gene regulation during the development of other epithelial tissues. Our data suggest a paradigm that p63 bookmarks genomic loci during the commitment of the epithelial lineage and regulates gene expression in different epithelial tissues through tissue-specific active enhancers. The catalogue of differentially expressed epidermal genes including non-coding RNAs and epithelial enhancers reported here provides a rich resource for studies of epithelial development and related diseases. Overall design: Comparison of gene expression at different stages of keratinocyte differentiation

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Oti M, Kouwenhoven EN, Zhou H