THE ROLE OF Nck ADAPTORS IN ENDOTHELIAL CELL POLARITY

Abstract

The establishment of a polarized endothelial layer is essential for normal vascular organization. This project examined the role of actin cytoskeleton remodeling by Nck adaptors in the polarized organization of endothelial cells. We assessed the role of Nck in the subcellular distribution of markers of polarity in cells cultured in two dimensions. Cellular levels of Nck were manipulated using tools of molecular genetics. Time-course experiments using control cells demonstrated that an incubation period of 2 h following the wounding of a confluent monolayer is optimum for the analysis of cell polarization. Our experimental results showed a significantly decreased index of cell polarization in Nck-depleted (shNck) vs. control or rescued cells (control ~59%; shNck, ~32%, and rescued ~55%). These findings strongly suggest an important role for Nck-dependent actin rearrangements in the establishment of polarity of endothelial cells. These studies open new avenues of research into the molecular mechanisms controlling the formation of polarized vascular networks.