Predicted to enable cargo adaptor activity. Predicted to be involved in receptor-mediated endocytosis. Predicted to be located in Golgi apparatus. Predicted to be part of AP-4 adaptor complex. Human ortholog(s) of this gene implicated in hereditary spastic paraplegia 51 and stuttering. Orthologous to human AP4E1 (adaptor related protein complex 4 subunit epsilon 1). [provided by Alliance of Genome Resources, Apr 2022]