Figure 1.

Model for the positive role of BAR domain proteins during endocytosis and vesicle trafficking. (A and B) extracellular cargo or receptors activated by ligand binding are targeted to clathrin-coated pits for internalization. (C) BAR domain proteins are recruited to the clathrin-coated pits to aid in assembly of the coat proteins and the initiation of endocytosis. The BAR proteins induce curvature of the membrane, reshaping the pit into a more spherical form. (D) BAR proteins further reshape the membrane by creating a long tubule between the plasma membrane and the newly formed vesicle. This newly formed tubule is the site for the action of Dynamin to facilitate scission of the vesicle from the overlying membrane. (E) BAR proteins also aid in the activation of the Arp2/3 complex, causing actin polymerization and vesicle trafficking further into the cytoplasm. Figure adapted from ref. 4.