Functions at the internalization step of the clathrin-mediated endocytosis (CME) as an early-acting scaffold protein. Requires clathrin adapter proteins, ENT1/2 and YAP1801/2, for normal spatiotemporal dynamics and viability. Binds to biological membranes in a ubiquitin-dependent manner. Interacts (via UBA domain) with monoubiquitin and ENT1 (via asparagine-proline-phenylalanine tripeptide motif called NPF). Interacts with PAL1 and SYP1. Localized to actin cortical patches concentrated in the developing bud tip in cells with small buds and at the mother-daughter neck in cells undergoing cytokinesis. Localization can be maintained in the absence of polymerized actin filaments. Random budding pattern and morphological defects. Defects in fluid-phase endocytosis and defective internalization of the pheromone alpha-factor and uracil permease. Deletion has only a small impact on actin cytoskeleton organization. Deletion shows synthetic growth defects with thermosensitive mutants of PAN1, END3 and RSP5. Present with 1380 molecules/cell in log phase SD medium. Belongs to the VDP/USO1/EDE1 family.