Notch signaling promotes the generation of EphrinB1-positive intestinal epithelial cells

Gastroenterology. 2009 Jul;137(1):145-55, 155.e1-3. doi: 10.1053/j.gastro.2009.03.046. Epub 2009 Mar 28.


Background & aims: The intestinal epithelium consists of EphB2-positive proliferative basal cryptic cells and EphrinB1-positive, postmitotic differentiated cells. We investigated the effects of Notch signaling on formation of the EphB2-EphrinB1 boundary using mouse and tissue culture models.

Methods: We created mice in which Mind bomb-1 (Mib1), an essential E3 ubiquitin ligase that activates Notch ligands, was inactivated specifically in the intestinal epithelia (Vil-Cre;Mib1(f/f)); Notch is, therefore, inactivated in this tissue. We also studied the effects of different inhibitors on intestinal epithelial cells (IEC-6) that express activated Notch. Tissues and cells were analyzed by immunohistochemical and immunoblot analyses.

Results: The intestinal epithelia of Vil-Cre;Mib1(f/f) mice had reduced numbers of EphrinB1-positive cells, compared with controls, but increases in EphB2-positive cells; beta-catenin was activated in these cells. These phenotypes were reversed by expression of a constitutively active form of Notch1. In the IEC-6 cells, Notch signaling activated the expression of EphrinB1 in an Hes1-independent manner, but down-regulated the expression of EphB2 through the GSK3beta-mediated inhibition of beta-catenin.

Conclusions: Notch signaling regulates formation of the EphB2-EphrinB1 boundary in the mouse intestinal epithelium.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Basic Helix-Loop-Helix Transcription Factors / metabolism
  • Cell Differentiation
  • Cell Line
  • Cell Lineage
  • Cell Proliferation
  • Ephrin-B1 / metabolism*
  • Ephrin-B2 / metabolism
  • Epithelial Cells / metabolism*
  • Glycogen Synthase Kinase 3 / metabolism
  • Glycogen Synthase Kinase 3 beta
  • Homeodomain Proteins / metabolism
  • Intestinal Mucosa / metabolism*
  • Mice
  • Mice, Transgenic
  • Microfilament Proteins / genetics
  • Microfilament Proteins / metabolism
  • Phosphorylation
  • Receptor, Notch1 / genetics
  • Receptor, Notch1 / metabolism*
  • Signal Transduction*
  • Stem Cells / metabolism*
  • Transcription Factor HES-1
  • Ubiquitin-Protein Ligases / genetics
  • Ubiquitin-Protein Ligases / metabolism
  • Wnt Proteins / metabolism
  • beta Catenin / metabolism


  • Basic Helix-Loop-Helix Transcription Factors
  • CTNNB1 protein, mouse
  • Efnb1 protein, mouse
  • Ephrin-B1
  • Ephrin-B2
  • Hes1 protein, mouse
  • Homeodomain Proteins
  • Microfilament Proteins
  • Notch1 protein, mouse
  • Receptor, Notch1
  • Transcription Factor HES-1
  • Wnt Proteins
  • beta Catenin
  • villin
  • MIB1 protein, mouse
  • Ubiquitin-Protein Ligases
  • Glycogen Synthase Kinase 3 beta
  • Gsk3b protein, mouse
  • Glycogen Synthase Kinase 3