Clathrin is the major protein of the polyhedral coat of coated pits and vesicles. In yeast, it is involved in the retention of proteins in an intracellular membrane compartment, presumably the trans-Golgi. Clathrin triskelions, composed of 3 heavy chains and 3 light chains, are the basic subunits of the clathrin coat. Interacts with the auxilin-like clathrin uncoating factor SWA2. Interacts with INP53. Cytoplasmic face of coated pits and vesicles. The C-terminal third of the heavy chains forms the hub of the triskelion. This region contains the trimerization domain and the light-chain binding domain involved in the assembly of the clathrin lattice. The N-terminal seven-bladed beta-propeller is formed by WD40-like repeats, and projects inward from the polyhedral outer clathrin coat. It constitutes a major protein-protein interaction node (By similarity). Present with 28700 molecules/cell in log phase SD medium. Belongs to the clathrin heavy chain family.