design: Assay for Transposase-Accessible Chromatin (ATAC) was performed according to [44] using AXIN2 and AXIN2- hepatocytes FACS-isolated from AXIN2CreERT2EGFP as described [5]. Briefly, 50k cells were permeabilized in lysis buffer (1% NP40, 10 mM TrisHcl, 2 mM NaCl, 3 mM MgCl2, Proteinase Inhibitor Cocktail (Roche)) for 10 min at 4C. Enriched nuclei were tagmented using 2.5 l of Tn5 transposase (Illumina Nextera DNA Library Prep Kit) in 50 l total volume at 37C for 30 min. The reaction was stopped and tagmented DNA was isolated using the MinElute Reaction Cleanup Kit (Qiagen). ATAC-seq libraries were generated using Illumina i7 and i5 primers with the Nextera Index Kit (Illumina) according to manufacturers instructions. Libraries were purified using Agencourt AMPure XP beads (Beckman Coulter) and their concentration was measured using Qubit dsDNA HS Assay Kit (Invitrogen). Library integrity and size distribution was checked by Agilent TapeStation. ATAC libraries were sequenced paired-end (2 x 76) on a HiSeq 4000 instrument (Illumina) according to manufacturers instructions.