FYVE domain found in WD40 repeat and FYVE domain-containing protein 3 (WDFY3) and similar proteins
WDFY3, also termed autophagy-linked FYVE protein (Alfy), is a ubiquitously expressed phosphatidylinositol 3-phosphate (PtdIns3P or PI3P) binding protein required for selective macroautophagic degradation of aggregated proteins. It regulates the protein degradation through the direct interaction with the autophagy protein Atg5. Moreover, WDFY3 acts as a scaffold that bridges its cargo to the macroautophagic machinery via the creation of a greater complex with Atg12, Atg16L, and LC3. It also functionally associates with sequestosome-1/p62 (SQSTM1) in osteoclasts. WDFY3 shuttles between the nucleus and cytoplasm. It predominantly localizes to the nucleus and nuclear membrane under basal conditions, but is recruited to cytoplasmic ubiquitin-positive protein aggregates under stress conditions. WDFY3 contains a PH-BEACH domain assemblage, five WD40 repeats and a PtdIns3P-binding FYVE domain.