Probable early component of the autophagy machinery being involved in formation of preautophagosomal structures and their maturation into mature phagosomes in response to PtdIns3P. May bind PtdIns3P. Interacts with TECPR1. Ubiquitously expressed. Highly expressed in heart, skeletal muscle and pancreas. Expression is down-regulated in pancreatic and in kidney tumors. Belongs to the WD repeat SVP1 family. 6 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.