Rapid induction and repression of genes mediated by barrier disruption. (A) Experimental approach for barrier disruption studies. Mice with shaved back skin were tape-stripped until TEWL measurements reached 40 g/m² ⋅ h. Skin was harvested before and at the indicated time points after TS. (B) Time course of TEWL before and up to 72 h after TS. TEWL in each group is shown as a bar graph with mean and SEM. (C) Overlap of differentially expressed genes at three time points after TS (6, 24, and 96 h) is shown by Venn diagrams (|log₂ fold change| ≥1, FDR <0.05). Up-regulated genes (UP) are shown on the left and down-regulated genes (DOWN) on the right. (D) GSEA comparing up-regulated genes at 6 or 24 h after TS with hallmark gene sets (H) in molecular signature database. Genes induced by Myc, or in response to unfolded proteins or TNFα signaling, were significantly enriched by the 6-h up-regulated subset, whereas genes that support mTORC1 signaling, G2M transition, and oxidative phosphorylation were enriched by the 24-h up-regulated subset. Enrichment profiles are plotted and calculated ES, P values (P val), and FDR are shown. (E) Heatmap representation of K-means clustering of differentially expressed genes before and after TS (|log₂ fold change| ≥1, FDR <0.05). Expression of genes associated with functional categories in each cluster is shown in box-whisker plots of log₂ normalized read counts from RNA-seq data. Whiskers extend from the smallest to the largest expression value within each cluster. Expression at 6, 24, and 96 h was compared with 0 h, and P values for expression difference were determined by one-way ANOVA analysis followed by Dunnett’s test. *, P < 0.05; ***, P < 0.005. (F) Expression of representative stress-responding genes as determined by RNA-seq at different time points after TS is shown for each cluster as bar graphs for normalized read counts with mean and SEM. P values for expression differences compared with 0 h were determined by DEseq2 analysis. *, P < 0.01; **, P < 0.001; ***, P < 0.0001. For TEWL studies (B), four independent experiments were performed with four to six mice per group. Two areas of back skin per mouse were processed for analysis (n = 8–12 per group). For transcriptional studies (C–F), RNA-seq datasets were generated from two independent experiments with pooled samples from 0 h (n = 4), 6 h (n = 4), and 24 h (n = 4) and from one experiment with pooled samples for 96 h (n = 2).