Epithelium from proximal 1/3 of mouse intestine was isolated by incubation with 5mM EDTA in PBS for 45 minutes at 4°C. Cells were snap-frozen in liquid nitrogen and used for subsequent ChIP analysis. Whole cell lysates were sonicated and incubated with H3K4me3 antibody overnight (Diagenode C15410003 ) for immunoprecipitation. ThruPLEX DNA-seq Kit (Rubicon Genomics) was used to prepare libraries, and 75 bp single-end reads were sequenced on an Illumina NextSeq 500 instrument.