Extended Data Figure 1. Analysis of one-month old Csf1r^MeriCreMer; BRAF^LSL-V600E; Rosa26^LSL-YFP mice.

(a) % of mice born from the cross depicted in Figure 1a according to their genotype (n=42), but no injection of hydroxy-tamoxifen (4-OHT) to test for adverse effects of 4-OHT administration. (b) Flow cytometry analysis of YFP expression on blood leukocytes. Representative for n=8 per genotype. (c) Flow cytometry analysis of YFP⁺ cells in the liver. YFP⁺ cells, present only in Csf1r^MeriCreMer+ (Cre⁺) mice (upper panels), fall into the F4/80⁺CD11b⁺ Kupffer cell gate (lower panels). Representative for n=8 per genotype. (d) YFP expression by immunofluorescence in the liver of BRAF^VE mice and BRAF^WT. YFP⁺ cells are F4/80⁺ Kupffer cells. Representative of n=6 mice per genotype. Scale bars=200 µm (5 µm for insets). (e) Total tissue-resident macrophages cell numbers per gram (g) of tissue were analyzed by flow cytometry in BRAF^VE mice (n=4) and BRAF^WT (n=6). Circles represent individual mice. Unpaired two-tailed t-test. (f) In situ analysis of phospho-Histone H3 (pHis3) staining in YFP⁺ cells from brains of BRAF^VE and BRAF^WT. Circles represent individual mice (n=3). Unpaired two-tailed t-test. (g) RNA-seq analysis, heatmap representation of MAPK target genes in YFP⁺ microglia from BRAF^VE (n=3) and BRAF^WT (n=2) mice, values are displayed as z-score. (h) Histological analysis of liver, lung, kidney and spleen in BRAF^VE mice and BRAF^WT. Representative of n=4 mice per genotype. Scale bars=200µm (10µm for insets).