AP2A1 encodes the alpha 1 adaptin subunit of the adaptor protein 2 (AP-2) complex found in clathrin coated vesicles. Adaptor protein (AP) complexes are cytosolic heterotetramers that mediate the sorting of membrane proteins in the secretory and endocytic pathways. AP complexes also play a pivotal role in the cargo selection by recognizing the sorting signals within the cytoplasmic tail of integral membrane proteins.
