Figure 5. Actin mediated E-cadherin clustering and E-cadherin endocytosis balance each other during adherens junction assembly.

Schematic showing the three stages of de novo adherens junction assembly – contact initiation, contact expansion and junction maturation. Contact initiation is characterized by branched actin network at the leading edge of the cells. E-cadherin clustering mediates actin filament remodeling from branched array to linear filaments which anchor adherens junctions complexes, leading to the contact expansion phase. This is followed by an inhibition of protrusive activity and junction maturation. Endocytosis acts to remove E-cadherin-catenin complexes that are not actin anchored during contact expansion thus contributing negatively to contact expansion. The actin driven clustering supersedes endocytosis mediated removal of E-cadherin at the cell surface to drive adherens junction assembly.