One of two major clathrin-associated adaptor complexes, AP-2, is a heterotetramer which is associated with the plasma membrane. This complex is composed of two large chains, a medium chain, and a small chain. This gene encodes the small chain of this complex. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2014],AP17, CLAPS2, FBH3, FBHOk, HHC3,Neurodegenerative Diseases,Neuroscience,Signal Transduction,AP2S1