Project description:Transcription factor Foxq1 controls mucin gene expression and granule content in mouse stomach surface mucous cells ; Background and Aims: The gastric mucosa provides a stringent epithelial barrier and produces acid and enzymes that initiate digestion. In this regenerating tissue, progenitors differentiate continually into 4 principal specialized cell types, yet underlying mechanisms of differentiation are poorly understood. We identified stomach-restricted expression of the forkhead transcription factor FOXQ1. Methods: We used a combination of genetic, histochemical, ultrastructural and molecular analysis to study gastric cell lineages with respect to FOXQ1. Results: Within the developing and adult gastrointestinal tract, Foxq1 mRNA is restricted to the stomach, expressed prominently in foveolar (pit) cells, the abundant mucin-producing cells that line the mucosal surface, and required for their complete differentiation. Mice carrying Foxq1 coding mutations show virtual absence of mRNA and protein for the backbone of the predominant stomach mucin, MUC5AC. These observations correspond to a paucity of foveolar-cell secretory vesicles and notable loss of stomach but not intestinal mucus. Transcriptional profiling identified a surprisingly restricted set of genes with altered expression in Foxq1 mutant stomachs. MUC5AC is a highly tissue-restricted product that similarly depends on FOXQ1 in its other major site of expression, conjunctival goblet cells. Conclusions: Taken together, these observations imply that promotion of gastric MUC5AC synthesis is a primary, cell-autonomous function of FOXQ1. This study is the first to implicate a transcription factor in terminal differentiation of foveolar cells and begins to define the requirements to assemble highly specialized organelles and cells in the gastric mucosa. DOI: 10.1053/j.gastro.2008.04.019 Experiment Overall Design: RNA from stomach antrum from 2 of each Satin, Beige, and BL6 mice were compared using microarray analysis.
Project description:We prepared miRNA from myofibroblats derived from normal stomach, both antrum (A) and corpus (C) separately and gastric cancers. miRCURYTM LNA Array ver5 was performed and comparisons were made by the dual (reference) method.
Project description:A small RNA library of stomach antrum tissue was sequenced using high-throughput SOLiD sequencing technology. The study aims to provide complementary information of the role of miRNAs in molecular regulation process in the healthy human stomach, in order to establish a reference for future comparisons of altered miRNA expression due to the gastric tract diseases.
Project description:Transcription factor Foxq1 controls mucin gene expression and granule content in mouse stomach surface mucous cells Background and Aims: The gastric mucosa provides a stringent epithelial barrier and produces acid and enzymes that initiate digestion. In this regenerating tissue, progenitors differentiate continually into 4 principal specialized cell types, yet underlying mechanisms of differentiation are poorly understood. We identified stomach-restricted expression of the forkhead transcription factor FOXQ1. Methods: We used a combination of genetic, histochemical, ultrastructural and molecular analysis to study gastric cell lineages with respect to FOXQ1. Results: Within the developing and adult gastrointestinal tract, Foxq1 mRNA is restricted to the stomach, expressed prominently in foveolar (pit) cells, the abundant mucin-producing cells that line the mucosal surface, and required for their complete differentiation. Mice carrying Foxq1 coding mutations show virtual absence of mRNA and protein for the backbone of the predominant stomach mucin, MUC5AC. These observations correspond to a paucity of foveolar-cell secretory vesicles and notable loss of stomach but not intestinal mucus. Transcriptional profiling identified a surprisingly restricted set of genes with altered expression in Foxq1 mutant stomachs. MUC5AC is a highly tissue-restricted product that similarly depends on FOXQ1 in its other major site of expression, conjunctival goblet cells. Conclusions: Taken together, these observations imply that promotion of gastric MUC5AC synthesis is a primary, cell-autonomous function of FOXQ1. This study is the first to implicate a transcription factor in terminal differentiation of foveolar cells and begins to define the requirements to assemble highly specialized organelles and cells in the gastric mucosa. Keywords: mutant mouse stomach
Project description:Stomach and intestinal epithelial cells are maintained by the activity of stem cells located in the isthmus and crypt, respectively1,2. Recent studies have demonstrated a surprisingly conserved role for Wnt signaling in stomach and intestinal development and stem cells3,4. Although accumulating evidence suggests that intestinal stromal cells secrete Wnt ligands to promote stem cell renewal5-10, the source of stomach Wnt ligands is still unclear. Moreover, how these gastrointestinal stem cell niche signals are produced is currently unknown. By performing single cell analysis of gastrointestinal stromal cells, we identified cell populations with transcriptome signatures that are conserved between the stomach and intestine. In close proximity to gastrointestinal epithelial cells, these cells highly expressed pericyte markers and Wnt ligands. They also were enriched for Hh signaling, which plays a key role in gut development11,12. A recent study has shown that intestinal pericryptal cells co-express Hh target and Wnt ligand genes8. To define their relationship, we analyzed mice with Hh gain of function in the pericyte-like stromal cells conserved between the stomach and intestine, and found increased levels of Wnt ligands, supporting Hh regulation of stromal Wnt ligand expression. Moreover, utilizing Sufu and Spop double knockout mice, which stabilized GLI2, a key Hh mediator in the gut, we were able to map GLI2 binding sites genome-wide and analyze super enhancers. This work demonstrates GLI2 activation of stromal Wnt ligands through enhancers that are conserved between the stomach and intestine. To determine the significance of Wnt secreting gastrointestinal stromal cells, we genetically inhibited Wnt secretion from the perictye-like or broad stromal cells, demonstrating their roles in gastrointestinal regeneration and development, respectively. Our work not only identifies the conserved gastrointestinal stromal niche cell populations but also reveals their underlying signaling and epigenetic mechanisms.
Project description:Analysis of global gene expression in the antral portion of the stomach in control and mice with a developing tumor to get further insight into the exact tumor type and the influence of local gene expression. Total RNA obtained from tissue samples from the antrum. Follow up of gene expression over the time of the tumor development
Project description:Murine Adult Stomach Small RNA Stomach samples were collected from adult mice. Small RNA was isolated from samples and cDNA libraries were generated for PGM sequencing. Sequences were aligned with Torrent Server tMap.