TCF-1 maintains the chromatin landscape of CD8⁺ T cells to suppress Tc17 potential. (A) Heat map of regions of chromatin accessibility across the genomes of Tcf7^−/− Tc17 cells (TCRβ⁺CD4⁻CD8⁺CD44⁺CD62L⁻CD25⁺), effector (TCRβ⁺CD4⁻CD8⁺CD44⁺CD62L⁻CD25⁻) and memory (TCRβ⁺CD4⁻CD8⁺CD44⁺CD62L⁺CD25⁻) CD8⁺ T cells from Tcf7^+/+ and Tcf7^−/− mice. Average relative peak abundance (Z-score) calculated from two independent biological replicates from log2-CPM value of peak regions. (B) Correlation analysis of DE genes from RNA-seq analysis of Tcf7^+/+ effector CD8⁺ T cells and Tcf7^−/− Tc17 cells (x axis) with gene accessibility (y axis). The green line is the regression line with a slope of 0.48. P value of the linear regression analysis is shown in the figure. (C) Overlap of DE genes from RNA-seq analysis and genes associated with differentially accessible chromatin regions in Tcf7^−/− Tc17 cells and Tcf7^+/+ effector CD8⁺ T cells. (D) Genome browser of normalized ATAC-seq reads across the Il17a and Il17f loci from Tcf7^−/− Tc17 and effector CD8⁺ T cells from Tcf7^+/+ and Tcf7^−/− mice. Predicted transcription factor binding sites are listed below as assessed by using the evolutionary rate covariance browser. (E) De novo motif analysis using HOMER in regions of chromatin with increased accessibility in Tc17 cells. Eff, effector CD8⁺ T cells; Mem, memory CD8⁺ T cells.