RNA regulons are essential in intestinal homeostasis

Abstract

Intestinal epithelial cells are among the most rapidly proliferating cell types in the human body. There are several different subtypes of epithelial cells, each with unique functional roles in responding to the ever-changing environment. The epithelium's ability for rapid and customized responses to environmental changes requires multitiered levels of gene regulation. An emerging paradigm in gastrointestinal epithelial cells is the regulation of functionally related mRNA families, or regulons, via RNA-binding proteins (RBPs). RBPs represent a rapid and efficient mechanism to regulate gene expression and cell function. In this review, we will provide an overview of intestinal epithelial RBPs and how they contribute specifically to intestinal epithelial stem cell dynamics. In addition, we will highlight key gaps in knowledge in the global understanding of RBPs in gastrointestinal physiology as an opportunity for future studies.

Fig. 1.

Schematic of RNA-binding protein (RBP) expression during homeostasis and disease. RBPs are preferentially expressed in intestine and colon crypts. Brackets indicate general area where expression has been observed. Arrows indicate expression described in a specific cell type. Font size indicates relative expression levels. During homeostasis, yellow box indicates that overexpression can lead to deregulated crypt proliferation and tumorigenesis, green box indicates that altered expression of the RBP does not affect homeostasis, and blue indicates that deregulated expression of the RBP affects homeostasis but has not been shown to induce tumorigenesis. During injury or disease, a red box indicates expression of the RBP is increased during intestinal regeneration and cancer, while orange indicates that expression is associated with cancer. CBC, crypt base columnar cell.