Abstract
The role of desmosomal cadherin desmocollin-2 (Dsc2) in regulating barrier function in intestinal epithelial cells (IECs) is not well understood. Here, we report the consequences of silencing Dsc2 on IEC barrier function in vivo using mice with inducible intestinal-epithelial-specific Dsc2 knockdown (KD) (Dsc2ERΔIEC). While the small intestinal gross architecture was maintained, loss of epithelial Dsc2 influenced desmosomal plaque structure, which was smaller in size and had increased intermembrane space between adjacent epithelial cells. Functional analysis revealed that loss of Dsc2 increased intestinal permeability in vivo, supporting a role for Dsc2 in the regulation of intestinal epithelial barrier function. These results were corroborated in model human IECs in which Dsc2 KD resulted in decreased cell-cell adhesion and impaired barrier function. It is noteworthy that Dsc2 KD cells exhibited delayed recruitment of desmoglein-2 (Dsg2) to the plasma membrane after calcium switch-induced intercellular junction reassembly, while E-cadherin accumulation was unaffected. Mechanistically, loss of Dsc2 increased desmoplakin (DP I/II) protein expression and promoted intermediate filament interaction with DP I/II and was associated with enhanced tension on desmosomes as measured by a Dsg2-tension sensor. In conclusion, we provide new insights on Dsc2 regulation of mechanical tension, adhesion, and barrier function in IECs.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 753-768 |
| Number of pages | 16 |
| Journal | Molecular biology of the cell |
| Volume | 32 |
| Issue number | 8 |
| DOIs | |
| State | Published - Apr 15 2021 |
Funding
The authors thank Roland Hilgarth and Jenna R. Brokaw for technical assistance as well as Kyle H. Smith for his help with the electron microscopy images. The authors also thank the Transgenic and Gene Targeting Core at Emory University, Microscopy and Image Analysis Laboratory and the Unit for Laboratory Animal Medicine (ULAM) at the University of Michigan Medical School. This work was supported by the following grants: Crohn's and Colitis Foundation Research Fellowship no. 623536 (A.R.-S.), German Research Foundation Research Fellowship DFG FL 870/1-1 (S.F.), and the People Program (Marie Curie Actions) of the European Union's Seventh Framework Program (FP7/2007-2013) under REA grant agreement no. 608765 (D.H.M.K.), as well as National Institutes of Health (Musculoskeletal and Skin Diseases) R01 AR041836 and R37 AR43380 (K.J.G.); Harvard Digestive Diseases Center (Microscopy and Histopathology Core B) P30 DK034854 (S.J.H.), R35 GM119617, R03 AR068096 (D.C.), R01 DK61739, DK72564, DK79392 (C.A.P.), R01 DK059888 and DK055679, DK089763 (A.N.); and University of Michigan Center for Gastrointestinal Research (UMCGR) (NIDDK 5P30DK034933). The authors thank Roland Hilgarth and Jenna R. Brokaw for technical assistance as well as Kyle H. Smith for his help with the electron microscopy images. The authors also thank the Transgenic and Gene Targeting Core at Emory University, Microscopy and Image Analysis Laboratory and the Unit for Laboratory Animal Medicine (ULAM) at the University of Michigan Medical School. This work was supported by the following grants: Crohn’s and Colitis Foundation Research Fellowship no. 623536 (A.R.-S.), German Research Foundation Research Fellowship DFG FL 870/1-1 (S.F.), and the People Program (Marie Curie Actions) of the European Union’s Seventh Framework Program (FP7/2007-2013) under REA grant agreement no. 608765 (D.H.M.K.), as well as National Institutes of Health (Musculoskeletal and Skin Diseases) R01 AR041836 and R37 AR43380 (K.J.G.); Harvard Digestive Diseases Center (Microscopy and Histopathology Core B) P30 DK034854 (S.J.H.), R35 GM119617, R03 AR068096 (D.C.), R01 DK61739, DK72564, DK79392 (C.A.P.), R01 DK059888 and DK055679, DK089763 (A.N.); and University of Michigan Center for Gastrointestinal Research (UMCGR) (NIDDK 5P30DK034933).
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology