Module 4: Figure cargo sorting signals
Cargo recognition by sorting proteins.
A wide range of cargo proteins located in the plasma membrane have specific sorting signals that are recognized by various sorting proteins. These sorting proteins have a variety of motifs that recognize both the sorting signals on the cargo proteins as well as clathrin. These sorting proteins also have lipid-binding motifs enabling them to bind to phosphatidyl 4,5-bisphosphate (PtdIns4,5P2). The ability of the sorting proteins to connect cargo proteins to the clathrin coat is an essential part of the process of endocytosis (Module 4: Figure endocytosis).