WD repeat domain phosphoinositide-interacting protein 1 (WIPI-1), also known as Atg18 protein homolog (ATG18) and WD40 repeat protein interacting with phosphoinositides of 49 kDa (WIPI 49 kDa), is a protein that in humans is encoded by the WIPI1 gene.
WD40 repeat proteins are key components of many essential biologic functions. They regulate the assembly of multiprotein complexes by presenting a beta-propeller platform for simultaneous and reversible proteinâÂÂprotein interactions. Members of the WIPI subfamily of WD40 repeat proteins, such as WIPI1, have a 7-bladed propeller structure and contain a conserved motif for interaction with phospholipids.