GSE158112
RNA-seq of untreated and IMQ treated mouse back skin in control and Ovol1 deficient mice
Skin constitutes the outer permeability barrier that protects the body from dehydration and a myriad of external assaults. Epidermal keratinocytes act as the first line of innate immune defense, and barrier defects underlie common inflammatory skin diseases. However, the molecular mechanisms that maintain barrier integrity when skin is under challenge to regulate the interplay between epidermal and immune cells are not fully understood. Here we report upregulated expression of transcriptional repressorencoding Ovol1 in epidermal cells of inflamed skin, and its functional importance in maintaining barrier integrity of physically or chemically challenged skin. Following stimulation with imiquimod, Ovol1-deficient mice exhibit significantly aggravated epidermal hyperplasia and psoriasis-like skin inflammation featuring persistent neutrophil accumulation. Using bulk and single-cell RNA-sequencing, we characterize molecular changes in epidermal, fibroblasts, and immune cells that reflect altered epidermal proliferation and differentiation and/or significantly enhanced inflammatory responses as consequences of Ovol1 deletion. We identify both proliferation/differentiation-regulating and neutrophil-attracting chemokine genes as candidate direct targets of Ovol1. Finally, we provide evidence for altered IL-1a signaling in the microenvironment of Ovol1- deficient inflamed skin that functionally contributes to neutrophil accumulation and epidermal hyperplasia. Collectively, our study demonstrates a protective role for an epidermally expressed, disease-linked transcription factor in coordinating robust barrier maintenance with suppression of skin inflammation. Overall design: RNA-seq of four untreated and four IMQ treated mouse back skin samples in control and Ovol1 deficient mice. Replicates consist of males and females.