Once the basic components of the docking complex are assembled with one end of AP-1 bound to cargo molecules, the other end binds to clathrin. Clathrin triskelions polymerize into hexagons and pentagons, forming a cage, which leads to membrane deformation. This polymerization step drives the sculpting of the lysosome vesicle. Here only 5 clathrin triskelions are represented, though in reality many more would be involved in sculpting an entire vesicle.