AP4E1

AP-4 complex subunit epsilon-1 is a protein that in humans is encoded by the AP4E1 gene.

Function
The heterotetrameric adaptor protein (AP) complexes sort integral membrane proteins at various stages of the endocytic and secretory pathways. AP4 is composed of 2 large chains, beta-4 (AP4B1) and epsilon-4 (AP4E1; this gene), a medium chain, mu-4 (AP4M1), and a small chain, sigma-4 (AP4S1).

Clinical relevance
It is currently hypothesized that AP4-complex-mediated trafficking plays a crucial role in brain development and functioning.