Predicted to enable clathrin adaptor activity. Acts upstream of or within several processes, including digestive tract development; kidney development; and post-Golgi vesicle-mediated transport. Predicted to be part of clathrin adaptor complex. Predicted to be active in clathrin-coated vesicle. Is expressed in several structures, including digestive system; eye; heart; intestinal bulb primordium; and pleuroperitoneal region. Orthologous to human AP1M2 (adaptor related protein complex 1 subunit mu 2).