Laminin α5 influences the architecture of the mouse small intestinal mucosa

The villus basement membrane is rich in laminin α5. Here the authors show that diminution of laminin α5 in a mouse model led to a compensatory deposition of colonic laminins that resulted in a transformation from a small intestinal to a colonic mucosal architecture. The alteration in mucosal architecture was associated with reduced levels of nuclear p27Kip1, a cell cycle regulator, and altered intestinal epithelial cell proliferation, migration, and differentiation. The results suggest that laminin α5 plays a crucial role in establishing and maintaining the specific mucosal pattern of the mouse small intestine.