Dataset Information

The LIN28B-IMP1 post-transcriptional regulon has opposing effects on oncogenic signaling in the intestine

ABSTRACT: Aim: RNA binding proteins (RBPs) are expressed broadly during both development and malignant transformation, yet their mechanistic roles in epithelial homeostasis or as drivers of tumor initiation and progression are incompletely understood. Method: Here we describe a novel interplay between RBPsLIN28B and IMP1 in intestinal epithelial cells. Ribosome-profiling and RNA-sequencing identifies IMP1 as a principle nodefor gene expression regulation downstream of LIN28B. Results: In vitro and in vivo data demonstrate that epithelial IMP1 loss increases expression of WNT target genes and enhances LIN28B-mediated intestinal tumorigenesis, which was reversed when we overexpressed IMP1 independently in vivo. Furthermore, IMP1 loss in wild type or LIN28B-overexpressing mice enhancesthe regenerative response to irradiation. Conclusions: Together, our data provide new evidence for the opposing effects of the LIN28B-IMP1 axis on post-transcriptional regulation of canonical WNT signaling, with implications in intestinal homeostasis, regeneration and tumorigenesis.

ORGANISM(S): Homo sapiens

PROVIDER: GSE115647 | GEO | 2018/12/27

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Aim: RNA binding proteins (RBPs) are emerging as critical regulators of gut homeostasis via post-transcriptional control of key growth and repair pathways. IMP1 (IGF2 mRNA Binding Protein 1) is ubiquitously expressed during embryonic development and Imp1 hypomorphic mice exhibit severe gut growth defects. In the present study, we investigated the mechanistic contribution of intestinal epithelial IMP1 to gut homeostasis and response to injury. Method: We evaluated IMP1 expression in patients with Crohn’s disease followed by unbiased ribosome profiling in IMP1 knockout cells. Concurrently, we measured differences in histology and cytokine expression in mice with intestinal epithelial-specific Imp1 deletion (Imp1ΔIEC) following dextran sodium sulfate (DSS)- colitis. Based on ribosome profiling analysis, we evaluated changes in autophagy in Imp1ΔIEC mice as well as in silico and in vitro approaches to evaluate direct protein:RNA interactions. Finally, we analyzed the consequence of genetic deletion of Atg7 in Imp1ΔIEC mice using colitis and irradiation models. Results: IMP1 was robustly upregulated in Crohn’s disease patients and Imp1 loss lessened DSS-colitis severity. Unbiased ribosome-profiling revealed that IMP1 may coordinate translation of multiple pathways important for intestinal homeostasis, including cell cycle and autophagy, which we verified by Western blotting. Mechanistically, we observed evidence for increased autophagy flux in Imp1ΔIEC mice, reinforced through in silico and biochemical analyses revealing direct binding of IMP1 to autophagy transcripts. Finally, we found genetic deletion of Atg7 reversed the phenotype observed in DSS- or irradiation-challenged Imp1ΔIEC mice. Conclusions: IMP1 acts as a post-transcriptional regulator of gut epithelial repair, in part through modulation of autophagy. This study highlights the need for examining post-transcriptional regulation as a critical mechanism in inflammatory bowel disease.

Dataset Information

The LIN28B-IMP1 post-transcriptional regulon has opposing effects on oncogenic signaling in the intestine

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure