An inducible mouse model for microvillus inclusion disease reveals a role for myosin Vb in apical and basolateral trafficking

Kerstin Schneeberger, Georg F Vogel, Hans Teunissen, Domenique D van Ommen, Harry Begthel, Layla El Bouazzaoui, Anke H M van Vugt, Jeffrey M Beekman, Judith Klumperman, Thomas Müller, Andreas Janecke, Patrick Gerner, Lukas A Huber, Michael W Hess, Hans Clevers, Johan H van Es, Edward E S Nieuwenhuis, Sabine Middendorp

Research output: Contribution to journal/periodicalArticleScientificpeer-review

Abstract

Microvillus inclusion disease (MVID) is a rare intestinal enteropathy with an onset within a few days to months after birth, resulting in persistent watery diarrhea. Mutations in the myosin Vb gene (MYO5B) have been identified in the majority of MVID patients. However, the exact pathophysiology of MVID still remains unclear. To address the specific role of MYO5B in the intestine, we generated an intestine-specific conditional Myo5b-deficient (Myo5b(fl/fl);Vil-CreERT2) mouse model. We analyzed intestinal tissues and cultured organoids of Myo5b(fl/fl);Vil-CreERT2 mice by electron microscopy, immunofluorescence, and immunohistochemistry. Our data showed that Myo5b(fl/fl);Vil-CreERT2 mice developed severe diarrhea within 4 d after tamoxifen induction. Periodic Acid Schiff and alkaline phosphatase staining revealed subapical accumulation of intracellular vesicles in villus enterocytes. Analysis by electron microscopy confirmed an almost complete absence of apical microvilli, the appearance of microvillus inclusions, and enlarged intercellular spaces in induced Myo5b(fl/fl);Vil-CreERT2 intestines. In addition, we determined that MYO5B is involved not only in apical but also basolateral trafficking of proteins. The analysis of the intestine during the early onset of the disease revealed that subapical accumulation of secretory granules precedes occurrence of microvillus inclusions, indicating involvement of MYO5B in early differentiation of epithelial cells. By comparing our data with a novel MVID patient, we conclude that our mouse model completely recapitulates the intestinal phenotype of human MVID. This includes severe diarrhea, loss of microvilli, occurrence of microvillus inclusions, and subapical secretory granules. Thus, loss of MYO5B disturbs both apical and basolateral trafficking of proteins and causes MVID in mice.

Original languageEnglish
Pages (from-to)12408-13
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume112
Issue number40
DOIs
Publication statusPublished - 06 Oct 2015

Fingerprint

Dive into the research topics of 'An inducible mouse model for microvillus inclusion disease reveals a role for myosin Vb in apical and basolateral trafficking'. Together they form a unique fingerprint.

Cite this