Temporal proteomics of NGF-TrkA signaling identifies an inhibitory role for the E3 ligase Cbl-b in neuroblastoma cell differentiation

Sci Signal. 2015 Apr 28;8(374):ra40. doi: 10.1126/scisignal.2005769.


SH-SY5Y neuroblastoma cells respond to nerve growth factor (NGF)-mediated activation of the tropomyosin-related kinase A (TrkA) with neurite outgrowth, thereby providing a model to study neuronal differentiation. We performed a time-resolved analysis of NGF-TrkA signaling in neuroblastoma cells using mass spectrometry-based quantitative proteomics. The combination of interactome, phosphoproteome, and proteome data provided temporal insights into the molecular events downstream of NGF binding to TrkA. We showed that upon NGF stimulation, TrkA recruits the E3 ubiquitin ligase Cbl-b, which then becomes phosphorylated and ubiquitylated and decreases in abundance. We also found that recruitment of Cbl-b promotes TrkA ubiquitylation and degradation. Furthermore, the amount of phosphorylation of the kinase ERK and neurite outgrowth increased upon Cbl-b depletion in several neuroblastoma cell lines. Our findings suggest that Cbl-b limits NGF-TrkA signaling to control the length of neurites.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / genetics
  • Adaptor Proteins, Signal Transducing / metabolism*
  • Cell Differentiation*
  • Cell Line, Tumor
  • Humans
  • MAP Kinase Signaling System*
  • Nerve Growth Factor / genetics
  • Nerve Growth Factor / metabolism*
  • Neurites / metabolism
  • Neurites / pathology
  • Neuroblastoma / genetics
  • Neuroblastoma / metabolism*
  • Neuroblastoma / pathology
  • Proto-Oncogene Proteins c-cbl / genetics
  • Proto-Oncogene Proteins c-cbl / metabolism*
  • Receptor, trkA / genetics
  • Receptor, trkA / metabolism*


  • Adaptor Proteins, Signal Transducing
  • NGF protein, human
  • Nerve Growth Factor
  • CBLB protein, human
  • Proto-Oncogene Proteins c-cbl
  • Receptor, trkA