Fig. 8: Synergy between promoter-based cytokine-response elements and distal enhancers.

a The Csn2 promoter region was characterized through ChIP-seq for STAT5, activating histone marks and Pol II loading at day one of lactation. The yellow and blue shades indicate the enhancers and promoters, respectively. The diagram shows the enhancer deletions and promoter mutations introduced in the mouse genome using CRISPR/Cas9 genome engineering and deaminase base editing, respectively. Red and yellow circles indicate Csn2 enhancers and promoters. b Csn2 mRNA levels were measured by RNA-seq in lactating mammary tissue (day one of lactation, L1) isolated from WT mice and mice carrying disabling mutations in the two GAS motifs in Csn2 promoter (ΔP) in the presence and absence of the three distal enhancers (ΔE1/2/3) (WT, ΔE1/2/3, ΔP-E1/2/3, n = 4; ΔP, n = 3). Results are shown as the means ± SEM of independent biological replicates. 2-way ANOVA followed by Dunnett’s multiple comparisons test was used to evaluate the statistical significance of differences between WT and each mutant mouse line. ***p < 0.0001, ****p < 0.00001. c Chromatin features of the Csn2 locus were investigated by ChIP-seq in lactating mammary tissue (day one of lactation, L1) of WT, ΔE1/2/3, ΔP and ΔP-E1/2/3 mice. The Cish locus served as ChIP-seq control. Source data are provided as a Source Data file.