AP4E1

Description

The AP4E1 (adaptor related protein complex 4 subunit epsilon 1) is a protein-coding gene located on chromosome 15.

AP-4 complex subunit epsilon-1 is a protein that in humans is encoded by the AP4E1 gene. 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). It is currently hypothesized that AP4-complex-mediated trafficking plays a crucial role in brain development and functioning.

AP4E1 is a component of the adaptor protein complex 4 (AP-4), which is involved in vesicle formation and cargo selection during protein transport. AP-4 forms a coat on vesicles that bud from the trans-Golgi network (TGN) and may be involved in targeting proteins to the endosomal-lysosomal system. It also plays a role in sorting proteins to the basolateral membrane in epithelial cells and localizing somatodendritic proteins in neurons. AP-4 recognizes and binds tyrosine-based sorting signals in cargo proteins, but may also recognize other sorting signals.

AP4E1 is also known as CPSQ4, SPG51, STUT1.

Associated Diseases

• Severe intellectual disability and progressive spastic paraplegia
• Spastic paraplegia 51, autosomal recessive
• Stuttering, familial persistent, 1