Modulation of N-cadherin junctions and their role as epicenters of differentiation-specific actin regulation in the developing lens

►In this manuscript we present novel findings that link cadherin junctions to tissue morphogenesis, in vivo, through their regulation of actin filament assembly. These studies were performed in the embryonic lens, a tissue ideally suited to questions regarding the mechanisms of morphogenesis. Acquisition of the lens cell differentiated phenotype requires lens epithelial cells to undergo a rapid and coordinated elongation. Here, we show that α-catenin is involved in differentiation-state specific maturation of N-cadherin junctions which are sites of recruitment of the actin regulators cortactin and Arp3 in vivo. We show that these N-cadherin junctions are responsible for organization of a cortical actin cytoskeleton and for the elongation of differentiating lens fiber cells, a process that is central to the morphogenesis of the lens. We believe our findings provide valuable information relevant to understanding the formation and function of many differentiated tissues.