InterPro domain: IPR026739

Adaptor protein (AP) complexes function in protein transport via transport vesicles in different membrane traffic pathways. AP complexes are involved in the formation of clathrin-coated vesicles (CCVs) by recruiting the scaffold protein, clathrin. AP complexes are also involved in the cargo selection by recognising the sorting signals in proteins. Several AP complexes have been identified: AP-2 mediates endocytosis from the plasma membrane, while AP-1, AP-3 and AP-4 play a role in the endosomal/lysosomal sorting pathways [ 1 , 2 ]. AP complexes are heterotetramers which consist of two large subunits, one medium subunit and one small subunit. One of the large subunits (alpha, gamma, delta and epsilon) mediates binding to the target membrane. The other large subunit (beta) recruits clathrin through the clathrin-binding sequence [ 3 ].

This entry represents the AP complexes beta subunit.

1. Adaptor protein complexes as the key regulators of protein sorting in the post-Golgi network. Cell Struct. Funct. 28, 419-29
2. Adaptors for clathrin coats: structure and function. Annu. Rev. Cell Dev. Biol. 20, 153-91
3. Biological basket weaving: formation and function of clathrin-coated vesicles. Annu. Rev. Cell Dev. Biol. 17, 517-68