AP2A1
Description
The AP2A1 (adaptor related protein complex 2 subunit alpha 1) is a protein-coding gene located on chromosome 19.
AP-2 complex subunit alpha-1 is a protein that in humans is encoded by the AP2A1 gene. This gene encodes the alpha 1 adaptin subunit of the adaptor protein 2 (AP2 adaptors) complex found in clathrin coated vesicles. The AP-2 complex is a heterotetramer consisting of two large adaptins (alpha or beta), a medium adaptin (mu), and a small adaptin (sigma). The complex is part of the protein coat on the cytoplasmic face of coated vesicles which links clathrin to receptors in vesicles. Alternative splicing of this gene results in two transcript variants encoding two different isoforms. A third transcript variant has been described, but its full length nature has not been determined. Adaptor-related protein complex 2, alpha 1 has been shown to interact with DPYSL2 and NUMB.
AP-2 complex subunit alpha-1 (AP2A1) is a component of the adaptor protein complex 2 (AP-2), which plays a crucial role in protein transport within cells. AP-2 complexes are involved in cargo selection and vesicle formation, specifically in clathrin-dependent endocytosis. This process involves the incorporation of cargo proteins into vesicles surrounded by clathrin (clathrin-coated vesicles, CCVs) that are destined for fusion with the early endosome. While clathrin provides a structural framework, AP-2 complexes act as major clathrin adaptors, binding directly to both the clathrin lattice and membrane components, facilitating CCV formation. AP-2 also serves as a cargo receptor, selectively sorting membrane proteins involved in receptor-mediated endocytosis. Additionally, AP-2 contributes to the recycling of synaptic vesicle membranes and recognizes specific endocytosis signal motifs within the cytosolic tails of transmembrane cargo molecules. It plays a role in maintaining post-endocytic trafficking through non-clathrin pathways and is responsible for the endocytosis of ADAM10 during long-term potentiation in hippocampal neurons. AP-2's alpha subunit binds to polyphosphoinositide-containing lipids, anchoring it to the membrane and serving as a scaffolding platform for endocytic accessory proteins. Both the alpha and sigma subunits are thought to be involved in recognizing specific endocytosis signal motifs.
AP2A1 is also known as ADTAA, AP2-ALPHA, CLAPA1.
Associated Diseases
- endometrial cancer
- esophageal cancer
- Griscelli syndrome type 3
- uncombable hair syndrome
- hemoglobin D disease
- oculocutaneous albinism type 3
- dehydrated hereditary stomatocytosis
