Desmocollin-2 promotes intestinal mucosal repair by controlling integrin-dependent cell adhesion and migration

Mol Biol Cell. 2020 Mar 15;31(6):407-418. doi: 10.1091/mbc.E19-12-0692. Epub 2020 Jan 22.

Abstract

The intestinal mucosa is lined by a single layer of epithelial cells that forms a tight barrier, separating luminal antigens and microbes from underlying tissue compartments. Mucosal damage results in a compromised epithelial barrier that can lead to excessive immune responses as observed in inflammatory bowel disease. Efficient wound repair is critical to reestablish the mucosal barrier and homeostasis. Intestinal epithelial cells (IEC) exclusively express the desmosomal cadherins, Desmoglein-2 and Desmocollin-2 (Dsc2) that contribute to mucosal homeostasis by strengthening intercellular adhesion between cells. Despite this important property, specific contributions of desmosomal cadherins to intestinal mucosal repair after injury remain poorly investigated in vivo. Here we show that mice with inducible conditional knockdown (KD) of Dsc2 in IEC (Villin-CreERT2; Dsc2 fl/fl) exhibited impaired mucosal repair after biopsy-induced colonic wounding and recovery from dextran sulfate sodium-induced colitis. In vitro analyses using human intestinal cell lines after KD of Dsc2 revealed delayed epithelial cell migration and repair after scratch-wound healing assay that was associated with reduced cell-matrix traction forces, decreased levels of integrin β1 and β4, and altered activity of the small GTPase Rap1. Taken together, these results demonstrate that epithelial Dsc2 is a key contributor to intestinal mucosal wound healing in vivo.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Cell Adhesion
  • Cell Movement*
  • Colitis, Ulcerative / metabolism
  • Colitis, Ulcerative / pathology
  • Desmocollins / metabolism*
  • Enterocytes / metabolism
  • Epithelial Cells / metabolism
  • Extracellular Matrix / metabolism
  • Gene Deletion
  • Humans
  • Inflammation / pathology
  • Integrins / metabolism*
  • Intestinal Mucosa / pathology*
  • Mice, Inbred C57BL
  • Wound Healing*
  • rap1 GTP-Binding Proteins / metabolism

Substances

  • Desmocollins
  • Integrins
  • Rap1 protein, mouse
  • rap1 GTP-Binding Proteins