Interferon Regulatory Factor 6 (IRF6) knockout in human keratinocytes disrupts epithelial homeostasis

The transcription factor Interferon Regulatory Factor 6 (IRF6) is crucially involved in craniofacial development and regulates the proliferation/differentiation balance in keratinocytes. Pathological IRF6 variants have been found in Van der Woude syndrome (VWS), the most common syndromic form of cleft lip / palate (CLP) as well as in non-syndromic CLP cases. Besides its prominent function in regulating keratinocyte differentiation, recent data revealed that IRF6 is also involved in wound healing and migration. Since a significant fraction of CLP patients undergoing corrective cleft surgery experience wound healing complications, IRF6 represents an interesting candidate gene linking the two processes. However, Irf6 function has been mainly studied in mice and knowledge on IRF6 in human cells remains sparse. Here, we aimed to elucidate the role of IRF6 in human postnatal skin- and oral mucosa-derived keratinocytes by its ablation using CRISPR/Cas9. We complement this approach by applying proteomics and identify that lack of IRF6 disrupts human epithelial homeostasis by altering cell colony morphology, migration pattern, and the differentiation potential of keratinocytes.