GSE67740
Hepatocyte Nuclear Factor 1 coordinates multiple functions of intestinal epithelial cells
Background and Aims: Hepatocyte nuclear factor 1 (HNF1) transcription factors direct tissue specific gene regulation in liver, pancreas and kidney and are associated with diabetes. Here we investigate the transcriptional network governed by HNF1 in an intestinal epithelial cell line. Methods: Chromatin immunoprecipitation followed by direct sequencing (ChIP-seq) was used to identify HNF1 binding sites genome-wide. Direct targets of HNF1 were validated using conventional ChIP assays. siRNA-mediated depletion of HNF1 followed by RT-qPCR further confirmed target genes.  The effect of HNF1 reduction on glucose uptake was measured by fluorescence activated cell sorting (FACS) following treatment of intestinal epithelial cells with 2-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl) amino]-2-deoxy-d-glucose (2-NBDG, a fluorescent glucose mimic). Results: HNF1 controls multiple pathways that are critical for intestinal epithelial cell function, including properties of the cell membrane, cellular response to hormones, and regulation of biosynthetic processes. Approximately 50% of HNF1 binding sites are also occupied by hepatocyte nuclear factor 4A (HNF4A), caudal type homeobox 2 (CDX2), and forkhead box A2 (FOXA2). Depletion of HNF1 increases FOXA2 abundance and decreases levels of CDX2. Moreover, loss of HNF1 inhibits glucose uptake by the intestinal epithelial cell line. Conclusions: These data show that HNF1 plays a critical role in regulating intestinal epithelial cell functions including glucose absorption. HNF1 interacts with other tissue-specific transcription factors to regulate differentiated properties of these cells. Overall design: To determine the role of HNF1 in regulating gene expression in intestinal epithelial cells, ChIP-seq was performed for HNF1 in Caco2 (colorectal adenocarcinoma) cells.