Identification of GATA-4 as a novel transcriptional regulatory component of regenerating islet-derived family members

摘要

Intestinal epithelial cells are exposed to luminal bacterial threat and require adequate defense mechanisms to ensure host protection and epithelium regeneration against possible deleterious damage. Differentiated intestinal epithelial cells produce antimicrobial and regenerative components that protect against such challenges. Few intestinal specific transcription factors have been identified to control the switching from repression to activation of this class of gene. Herein, we show that gene transcription of some regenerating islet-derived (REG) family members is dependent on the transcription factor GATA-4. Silencing of GATA-4 expression in cultured intestinal epithelial cells identified Reg3 beta as a target gene using an unbiased approach of gene expression profiling. Co-transfection and RNA interference assays identified complex GATA-4-interactive transcriptional components required for the activation or repression of Reg3 beta gene activity. Conditional deletion of Gata4 in the mouse intestinal epithelium supported its regulatory role for Regl, Reg3 alpha, Reg3 beta and Reg3 gamma genes. Regl dramatic down-modulation of expression in Gata4 conditional null mice was associated with a significant decrease in intestinal epithelial cell migration. Altogether, these results identify a novel and complex role for GATA-4 in the regulation of REG family members gene expression. (C) 2015 Elsevier B.V. All rights reserved.