library_construction_protocol: The initial third of the small intestine (duodenum) was dissected and opened longitudinally to wash the inter-lumen space and expose epithelial cells. Tissue was cut into 1-inch pieces and rinsed with ice-cold PBS. Tissue was treated with 3mM EDTA/PBS for 35 minutes, with changes in EDTA solution at the initial 5- and 10-minute time points. Mechanical force was applied to release the epithelial cell layer from the underlying mesenchyme. The epithelial cells were washed with PBS, and pelleted to remove excess PBS prior to addition of TRIzol for RNA extraction according to manufacturer's protocols.RNA extraction was performed using the RNeasy Micro Kit (Qiagen, 74004). Illumina TruSeq RNA Library Prep kit v2