NEDD4-binding protein 3 (N4BP3)

NEDD4-binding protein 3 (N4BP3) is a cytoplasmic adaptor protein and a member of the Fezzin family, characterized by a coiled-coil domain, a C-terminal Fez1 domain, and a highly conserved PY (PPxY) motif that mediates selective binding to the WW domains of the ubiquitin ligase NEDD4[1]. N4BP3 is expressed prominently in neural tissues including axons, dendrites, and growth cones, where it plays a crucial role in the proper branching and arborization of neuronal processes during development[1][3][6]. Loss of N4BP3 leads to abnormal axonal and dendritic morphology both in vitro and in vivo, suggesting it is essential for correct neural circuit formation[1]. Beyond neurodevelopment, N4BP3 has been shown to positively regulate antiviral innate immunity by interacting with MAVS (mitochondrial antiviral-signaling protein) to promote RIG-I-like receptor signaling and type I interferon production[5][3][6]. N4BP3 does not appear to function as an enzyme, receptor, transporter, or classical transcription factor, but rather as a modulator or adaptor protein collaborating with enzymes such as NEDD4. Although it is grouped with leucine zipper putative tumor suppressors (LZTS), its specific roles in cancer biology remain poorly understood. No approved or investigational drugs currently target N4BP3 directly, and it is not used clinically as a biomarker or established therapeutic target.

Other names

KIAA0341LZTS4Leucine zipper putative tumor suppressor 4N4BP3