May play a role in autophagy. May regulate the trafficking of proteins involved in the mannose-6-phosphate receptor (MPR) recycling pathway. Probably interacts with androgen (AR) and the estrogen receptor (ER). Binds PtdIns3P and to a lesser extent, PtdIns3,5P2 and PtdIns5P in vitro. Interaction with PtdIns3P is required for recruitment to membranes. 2 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.