Fig 5. cBAF is required for targeting of T-bet to enhancers in effector CD8⁺ T cells.

(A-B) As described in Figure 4, OCRs (2-fold change, adjusted p value<0.05, Benjamini-Hochberg) lost in Arid1a^cKO d5 effector cells or d8 TE, EEC, and MP subsets relative to WT cells were analyzed for enrichment of predicted TF motifs (A) or TF binding signals (observed/expected) of indicated TFs from public ChIP-seq datasets (GSE192390) in ARID1A-dependent (green) and - independent (gray) OCRs (B). (C) Genomic annotations and CUT&RUN signal heatmaps of ARID1A, BATF, ETS1, and T-bet at ARID1A-dependent or -independent OCRs from WT and Arid1a^cKO effector P14 CD8⁺ T cells d5 post-infection. (D-F) CD8⁺ T cells were activated in vitro for 48hrs and then treated with DMSO (black, red), ACBI1 (green) or BRM014 (purple) for 4 hours, and then treated with IL-12 (red, green, purple) for 2 hours, and analyzed for changes in ATAC-seq and T-bet binding by ChIP-seq. Signal coverage heatmaps of ATAC-seq and T-bet ChIP-seq (D) and histograms measuring chromatin accessibility (E) are shown. (F) Genomic annotations of ACBI1-dependent and -independent ATAC-seq OCRs. (G) Overlap of OCRs lost relative to WT (2-fold change, adjusted p value<0.05, Benjamini-Hochberg) in Arid1a^cKO or Tbx21 KO TE and MP cells. (H) ARID1A CUT&RUN signal heatmap in WT or Tbx21 KO effector cells at d5 p.i. Signal is centered on ARID1A- or Tbet-dependent OCR peaks identified in (G). (I) Retroviral overexpression of T-bet fails to rescue TE formation in Arid1a^cKO cells at d8 p.i. (J) T-bet CUT&RUN signal coverage histograms at Activation and Late Activation OCRs in WT or Arid1a^cKO cells transduced with either empty vector (EV) or T-bet overexpression (Tbet-OE) retrovirus at d5 p.i.*p<0.05, **p<0.005, ***p<0.0005.