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Updated: May 30, 2026
06:04
Ex Vivo Intestinal Sacs to Assess Mucosal Permeability in Models of Gastrointestinal Disease
Published on: February 9, 2016
Boundaries, junctions and transitions in the gastrointestinal tract
Adrianna K San Roman1, Ramesh A Shivdasani
1Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA 02215, USA.
Experimental Cell Research
|August 2, 2011
Summary
Understanding the gastrointestinal tract boundaries is crucial for studying diseases like cancer. This review explores the molecular and cellular mechanisms that form and maintain these vital tissue borders.
Area of Science:
- Gastroenterology
- Developmental Biology
- Molecular Biology
Background:
- The mammalian gastrointestinal tract exhibits distinct regions with sharp or imprecise boundaries, crucial for specialized digestive functions.
- Cancer and intestinal disorders often arise from altered tissue states, highlighting the importance of understanding boundary integrity.
- Knowledge of boundary formation mechanisms is essential for comprehending tissue organization and disease pathogenesis.
Purpose of the Study:
- To review the anatomical and molecular determinants of boundaries and transitions in the alimentary canal.
- To explore the transcriptional control of epithelial identity in maintaining tissue boundaries.
- To discuss molecular mechanisms, including transcription factors, involved in boundary formation.
Main Methods:
- Review of existing literature on gastrointestinal tract anatomy and physiology.
- Analysis of gene expression patterns and transcriptional regulation at tissue boundaries.
- Examination of genetic studies, particularly in mice, to elucidate boundary formation mechanisms.
Main Results:
- Gastrointestinal tract regions possess distinct boundaries, with some sharp (e.g., esophagus-stomach) and others imprecise (e.g., small intestine segments).
- Tissue morphology, gene expression, and transcriptional control of epithelial identity are key determinants of these boundaries.
- Transcription factors play significant roles, both individually and in combination, in establishing and maintaining tissue boundaries.
Conclusions:
- Understanding the molecular basis of gastrointestinal tract boundary formation is critical for investigating diseases like cancer and intestinal disorders.
- Transcriptional control of epithelial identity is a central mechanism in establishing and preserving tissue boundaries.
- Further research, informed by genetic studies in model organisms, is needed to fully elucidate the complex mechanisms governing these boundaries.
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