Disrupted transcriptional network in ?Np63 AEC tissue model [ChIP-Seq]

The transcriptional basis for disrupted epidermal differentiation arising from TP63 AEC mutations remains to be elucidated. Here we present an organotypic model of AEC dysfunction that phenocopies differentiation defects observed in AEC patient skin. Transcriptional analysis of model AEC tissue revealed impaired induction of differentiation regulators, including OVOL1, GRHL3, KLF4, PRDM1 and ZNF750. Genome wide binding analyses of TP63 during epidermal differentiation showed direct binding of OVOL1, GRHL3, and ZNF750 promoters suggesting AEC mutants prevent normal activation of these targets by direct transcriptional interference. Remarkably, exogenous ZNF750 restores impaired epidermal differentiation caused by AEC mutation. Thus, repression of ZNF750 is central to disrupted epidermal differentiation in model AEC tissue. Overall design: ChIP-Seq analysis: Examination of p63 binding in proliferating and differentiating human keratinocytes