The F-box protein FBXO7 positively regulates bone morphogenetic protein-mediated signaling through Lys-63-specific ubiquitination of neurotrophin receptor-interacting MAGE (NRAGE)

Jengmin Kang, Kwang Chul Chung

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10 Citations (Scopus)


Parkinson's disease (PD) is characterized by progressive midbrain dopaminergic neuron degeneration and the formation of intracellular protein aggregates, referred to as Lewy bodies. F-box only protein 7 (FBXO7) gene mutations are closely associated with progression of the autosomal recessive form of familial PD. FBXO7 encodes a component of Skp1, cullin, F-box ubiquitin ligase complexes; however, its cellular targets, including substrates and regulators, are not yet clarified. To identify potential substrates of FBXO7, we performed a yeast two-hybrid screen of a human fetal brain library and identified neurotrophin receptor-interacting MAGE protein (NRAGE) as a novel FBXO7-binding partner. We found that FBXO7 interacts with NRAGE and mediates Lys-63-linked poly-ubiquitination of NRAGE in mammalian cells. FBXO7 overexpression accelerates formation of NRAGE-TAK1-TAB1 complexes, whereas FBXO7 knockdown correspondingly decreases complex formation. In addition, BMP4 stimulation enhances NRAGE ubiquitination through FBXO7 and facilitates endogenous NRAGE-TAK1-TAB1 complex formation. Furthermore, FBXO7 positively regulates formation of the BMP receptor-NRAGE-TAK1-TAB1 complex, and up-regulates NF-κB activity. Taken together, our results suggest that FBXO7 affects BMP4-mediated signaling through proteasome-independent ubiquitination of NRAGE and augments formation of downstream signaling components.

Original languageEnglish
Pages (from-to)181-195
Number of pages15
JournalCellular and Molecular Life Sciences
Issue number1
Publication statusPublished - 2015 Jan


All Science Journal Classification (ASJC) codes

  • Molecular Medicine
  • Molecular Biology
  • Pharmacology
  • Cellular and Molecular Neuroscience
  • Cell Biology

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