WD Repeat Domain Phosphoinositide Interacting Protein 1 (WIPI1)

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 protein-protein 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. The deduced full-length WIPI1-alpha protein contains 7 WD-like repeats, conserved and invariant hydrophobic and polar residues, 2 invariant arginines that mediate phospholipid interaction, and 2 LxxLL motifs for nuclear receptor interaction. Northern blot analysis detected ubiquitous expression of an approximately 2.0-kb transcript. Highest expression was in testis, heart, and skeletal muscle.