Fig. 6: STAT1 regulates epithelial Myc expression in immune-mediated GI damage.

a Diagram of the Myc gene locus (NCBI Refseq) with mapping of the genome location, ATAC-seq peaks (blue) from sorted Lgr5^GFP ISCs (GSE83394), ENCODE (Accession EM10E0600598) candidate cis-regulatory elements (cCREs) indicating a proximal enhancer (black) and promoter regions (gray), and location of primers (red) used to detect STAT1 binding by qPCR following anti-STAT1 antibody and isotype control ChIP. b Δ% of input of anti-STAT1/isotype ChIP-qPCR of Irf1, Myc and negative control (NC) Foxp3 loci performed on ISC colonies treated with IFNγ (3 h, 1 ng/ml). c Myc and Ccnd1 qPCR analysis of mouse Stat1^WT or Stat1^ΔIEC SI organoids cultured ± IFNγ (n = 6 wells/group); Stat1^WT vs IFNγ, p = 0.0022 for both Myc and Ccnd1; Stat1^ΔIEC vs IFNγ, p = 0.0649 for Myc, p = 0.1255 for Ccnd1; combined from two independent experiments. d, e Allogeneic B10.BR-into-B6 BMT using Stat1^ΔIEC recipients or Stat1^WT littermate control recipients. d qPCR analysis of SI crypts harvested day 7 post-BMT (n = 9 Stat1^WT, 8 Stat1^ΔIEC recipients; combined from two independent experiments). e Immunofluorescent staining and quantification of c-Myc (green) in ileum (day 5 post-BMT; n = 9 independent sections each from 3 Stat1^WT and 3 Stat1^ΔIEC recipients; scale bars = 20 μm; two-tailed t test). f Olfm4-Cre x RiboTag (Olfm4-Ribo) mice were treated intraperitoneally with 20μg IFNγ or PBS twice, 48 and 24 h prior to harvest, as well as tamoxifen 20 h prior to harvest. Hemagglutinin-labeled Olfm4⁺ ISC ribosomes were then isolated from small intestine, and qPCR was performed on the associated RNA transcripts; n = 7 mice/group; combined from three independent experiments. Graphs indicate mean and s.e.m.; comparisons performed with two-tailed Mann–Whitney unless otherwise specified; ** p < 0.01, *** p < 0.001. The exact p values are p < 0.001 unless specified otherwise.