aV-Integrins Are Required for Mechanotransduction in

The properties of epithelial cells within tissues are regulated by their immediate microenvironment, which consists of neighboring cells and the extracellular matrix (ECM). Integrin heterodimers orchestrate dynamic assembly and disassembly of cell-ECM connections and thereby convey biochemical and mechanical information from the ECM into cells. However, the specific contributions and functional hierarchy between different integrin heterodimers in the regulation of focal adhesion dynamics in epithelial cells are incompletely understood. Here, we have studied the functions of RGD-binding aV-integrins in a Madin Darby Canine Kidney (MDCK) cell model and found that aV-integrins regulate the maturation of focal adhesions (FAs) and cell spreading. aV-integrin-deficient MDCK cells bound collagen I (Col I) substrate via a2b1-integrins but failed to efficiently recruit FA components such as talin, focal adhesion kinase (FAK), vinculin and integrin-linked kinase (ILK). The apparent inability to mature a2b1-integrin-mediated FAs and link them to cellular actin cytoskeleton led to disrupte