May influence APP processing, resulting in a decrease in sAPP-alpha production and increased amyloidogenic P3 peptide production (PubMed:21795536). May regulate ITCH and NEDD4 E3 ligase activity and degradation (By similarity). Interacts with APP precursor C-terminus (PubMed:21795536). Interacts directly with ITCH; this interaction promotes ITCH auto-ubiquitination leading to its degradation. Interacts directly with NEDD4; this interaction promotes NEDD4 auto-ubiquitination. Interacts directly with NEDD4L (By similarity). Expressed in the cerebral cortex and hippocampus. Belongs to the LDLR family.