This gene encodes the gamma-2 subunit of the adaptor protein complex 1 (AP-1). AP-1 complex is a heterotetramer comprised of two heavy and one each of medium and small subunits. The encoded protein is a heavy subunit of AP-1 complex that regulates polarized sorting of cargo at the trans-Golgi network and endosomes. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, Jan 2015]