Cooperation between HNF-1α, Cdx2, and GATA-4 in initiating an enterocytic differentiation program in a normal human intestinal epithelial progenitor cell line

Abstract

In the intestinal epithelium, the Cdx, GATA, and HNF transcription factor families are responsible for the expression of differentiation markers such as sucrase-isomaltase. Although previous studies have shown that Cdx2 can induce differentiation in rat intestinal IEC-6 cells, no data are available concerning the direct implication of transcription factors on differentiation in human normal intestinal epithelial cell types. We investigated the role of Cdx2, GATA-4, and HNF-1α using the undifferentiated human intestinal epithelial crypt cell line HIEC. These transcription factors were tested on proliferation and expression of polarization and differentiation markers. Ectopic expression of Cdx2 or HNF-1α, alone or in combination, altered cell proliferation abilities through the regulation of cyclin D1 and p27 expression. HNF-1α and GATA-4 together induced morphological modifications of the cells toward polarization, resulting in the appearance of functional features such as microvilli. HNF-1α was also sufficient to induce the expression of cadherins and dipeptidylpeptidase, whereas in combination with Cdx2 it allowed the expression of the late differentiation marker sucrase-isomaltase. Large-scale analysis of gene expression confirmed the cooperative effect of these factors. Finally, although DcamKL1 and Musashi-1 expression were downregulated in differentiated HIEC, other intestinal stem cell markers, such as Bmi1, were unaffected. These observations show that, in cooperation with Cdx2, HNF-1α acts as a key factor on human intestinal cells to trigger the onset of their functional differentiation program whereas GATA-4 appears to promote morphological changes.

Polycomb repressive complex 2 impedes intestinal cell terminal differentiation

“…It is noteworthy that under these conditions, expression of cell polarization markers such as E-cadherin, Li-cadherin and various tight junction components was triggered while terminal differentiation remained limited as evaluated by expression of low levels of SI mRNA transcript. Taking together, these data indicating that HIEC HNF1a/CDX2 are committed but still poorly differentiated suggest that they may share characteristics with the TA cells (Benoit et al, 2010). Consistent with this, we observed significant endogenous expression of the SUZ12 transcript in wildtype HIEC cells which was greatly increased following ectopic expression of HNF1a and CDX2 (Fig.…”

“…These include dipeptidylpeptidase IV (DPPIV) and aminopeptidase N (Gorvel et al, 1991;Quaroni et al, 1992) but also immature forms of other markers (Beaulieu et al, 1989;Beaulieu et al, 1990;Gorvel et al, 1991;Hoffman and Chang, 1993;Giannoni et al, 1995;Basque et al, 1998) including SI, one of the best characterized intestinal cell markers. The latter data are consistent with the fact that all cells in the TA zone express the transcription factors CDX2, HNF1a and HNF4a known to promote expression of differentiation markers such as SI (Traber, 1999;Mitchelmore et al, 2000;Boudreau et al, 2002b;Escaffit et al, 2005a;Olsen et al, 2005;Fang et al, 2006;Bosse et al, 2007;Boyd et al, 2009;Benoit et al, 2010;Boyd et al, 2010). These data suggest that in the TA zone, repressive mechanisms are responsible for the full suppression of terminal differentiation in rodents.…”

“…Consistent with the intestinal progenitor status of HIEC, previous studies confirmed the absence, or trace expression of digestive enzymes such as SI and DPPIV in wild-type cells (Perreault and Beaulieu, 1996;Pageot et al, 2000) but forced expression of HNF1a and CDX2 induced these enterocytic differentiation markers (Benoit et al, 2010). The impact of SUZ12 abolition on differentiation was thus studied in wild type and HNF1a/CDX2 overexpressing HIEC.…”

“…The HIEC model had been previously shown to display many characteristics associated with undifferentiated intestinal crypt cells (Perreault and Beaulieu, 1996;Pageot et al, 2000;Tremblay et al, 2006;Beaulieu and Ménard, 2012). Ectopic expression of transcription factors such as HNF1a and CDX2 in HIEC induced initiation of an intestinal cell differentiation program (Benoit et al, 2010). It is noteworthy that under these conditions, expression of cell polarization markers such as E-cadherin, Li-cadherin and various tight junction components was triggered while terminal differentiation remained limited as evaluated by expression of low levels of SI mRNA transcript.…”

Transcription Factors GATA4 and HNF4A Control Distinct Aspects of Intestinal Homeostasis in Conjunction with Transcription Factor CDX2

“…Efficient Depletion of TFs in Mouse Intestinal Epithelium-As GATA4 and CDX2 are implicated in the control of selected villus cell genes in vivo (15,36) and in replication of cultured progenitor cells (11), we first considered the intestinal GATA factors and crossed mice to obtain conditional Gata4…”